Applied Science, Faculty of
Electrical and Computer Engineering, Department of
DSpace
UBCV
Mokhberi, Azadeh
Master of Applied Science - MASc
University of British Columbia
Although peer-to-peer (P2P) marketplaces have become increasingly popular, they raise many trust, privacy, and safety issues. There is a growing interest among individuals in using such marketplaces for buying and selling second-hand items. Such platforms foster trading, and expand users’ access to a wide range of items with good prices. However, according to police and previous studies, such platforms raise many new trust challenges, privacy problems, and safety risks. Facebook Marketplace is one type of P2P marketplace platform. Facebook Marketplace (FM) and similar platforms have some unique characteristics that distinguish them from other, previously- studied marketplace platforms. We found a gap in investigating trust, privacy, and safety (TPS) on such platforms. More importantly, there is a lack of study of how FM users manage these aspects in trading. This thesis utilizes a human-centered approach to explore the trust, privacy, and safety aspects of trading on FM from the perspectives and experiences of users. To further facilitate the free expression of thoughts and the addition of information, a total of 42 1-on-1 interviews were conducted through Zoom with recruited various FM users, 19-75-year-olds, who lived in North America. We used this method to understand how FM users manage their TPS aspects during FM trading. To understand and visualize participants’ TPS aspects management, we developed two distinct frameworks that describe the TPS-related factors and strategies of participants. The research findings revealed the complex and multifaceted nature of these aspects. It also highlights the importance of five types of factors including pre-existing concerns, signals, social norms, perceived benefits, and platform design specifics that either hinder, promote, or influence the priority of TPS in shaping participants’ decision making around TPS when using FM. The results highlight that users employ four types of TPS-related strategies, namely: trader selection and screening, information collection and sharing, negotiation of in-person trading details, and in-person interaction. In this study, we have identified various types of challenges, tensions, trade-offs, and discrepancies that users faced. In conclusion, we emphasize the existing gaps in this area of research for future studies and offer recommendations for both researchers and designers.
Towards Understanding Trust, Privacy, and SafetyManagement Among Facebook Marketplace UsersbyAzadeh MokhberiMDes., University of Alberta, 2019A THESIS SUBMITTED IN PARTIAL FULFILLMENTOF THE REQUIREMENTS FOR THE DEGREE OFMaster of Applied ScienceinTHE FACULTY OF GRADUATE AND POSTDOCTORALSTUDIES(Electrical and Computer Engineering)The University of British Columbia(Vancouver)April 2023© Azadeh Mokhberi, 2023The following individuals certify that they have read, and recommend to the Fac-ulty of Graduate and Postdoctoral Studies for acceptance, the thesis entitled:Towards Understanding Trust, Privacy, and Safety Management AmongFacebook Marketplace Userssubmitted by Azadeh Mokhberi in partial fulfillment of the requirements for thedegree of Master of Applied Science in Electrical and Computer Engineering.Examining Committee:Konstantin Beznosov, Professor, Electrical and Computer Engineering, UBCSupervisorDongwook Yoon, Professor, Computer Science, UBCSupervisory Committee MemberKarthik Pattabiraman, Professor, Electrical and Computer Engineering, UBCSupervisory Committee MemberiiAbstractAlthough peer-to-peer (P2P) marketplaces have become increasingly popular, theyraise many trust, privacy, and safety issues. There is a growing interest amongindividuals in using such marketplaces for buying and selling second-hand items.Such platforms foster trading, and expand users’ access to a wide range of itemswith good prices. However, according to police and previous studies, such plat-forms raise many new trust challenges, privacy problems, and safety risks.Facebook Marketplace is one type of P2P marketplace platform. FacebookMarketplace (FM) and similar platforms have some unique characteristics that dis-tinguish them from other, previously-studied marketplace platforms. We found agap in investigating trust, privacy, and safety (TPS) on such platforms. More im-portantly, there is a lack of study of how FM users manage these aspects in trading.This thesis utilizes a human-centered approach to explore the trust, privacy, andsafety aspects of trading on FM from the perspectives and experiences of users. Tofurther facilitate the free expression of thoughts and the addition of information, atotal of 42 1-on-1 interviews were conducted through Zoom with recruited variousFM users, 19-75-year-olds, who lived in North America. We used this method tounderstand how FM users manage their TPS aspects during FM trading.To understand and visualize participants’ TPS aspects management, we devel-oped two distinct frameworks that describe the TPS-related factors and strategiesof participants. The research findings revealed the complex and multifaceted natureof these aspects. It also highlights the importance of five types of factors includ-ing pre-existing concerns, signals, social norms, perceived benefits, and platformdesign specifics that either hinder, promote, or influence the priority of TPS inshaping participants’ decision making around TPS when using FM. The resultsiiihighlight that users employ four types of TPS-related strategies, namely: trader se-lection and screening, information collection and sharing, negotiation of in-persontrading details, and in-person interaction. In this study, we have identified varioustypes of challenges, tensions, trade-offs, and discrepancies that users faced. In con-clusion, we emphasize the existing gaps in this area of research for future studiesand offer recommendations for both researchers and designers.ivLay SummaryThis thesis investigates how trust, privacy, and safety are managed on FacebookMarketplace when buying and selling second-hand items. We interviewed 42 Face-book Marketplace users aged 19 to 75 from North America to understand theirdecision-making process and strategies.The study found that people consider several factors related to trust, privacy,and safety when deciding whether to trade on Facebook Marketplace. These in-clude pre-existing concerns, signals, social norms, perceived benefits, and plat-form design. People use four different types of strategies to manage trust, privacy,and safety on Facebook Marketplace: trader selection and screening, informationcollection and sharing, negotiation of in-person trading details, and in-person in-teraction.Overall, the study showed that there are various factors and actions taken byusers to build trust, protect privacy, and stay safe when buying and selling on Face-book Marketplace. We suggested ways to improve the platform’s support for usersand opportunities for more research.vPrefaceIn developing this dissertation, I collaborated with the following individuals: YueHuang, Masoud Mehrabi Koushki, Borke Obada, and my advisor Konstantin Beznosovfrom the University of British Columbia. As the primary researcher, I was respon-sible for designing the entire user study, identifying research topics, developingresearch questions, designing the methodology for the dissertation, and conductingall of the user interviews. I conducted over 90% of the coding, analysis, and writ-ing. To minimize personal biases, Yue Huang and Guillaume Humbert participatedin the qualitative analysis of collected data. After the data analysis, all co-authorsprovided constructive feedback to refine the results, participated in group meet-ings to improve the frameworks, brainstormed the most effective way to presentthe findings, and proofread the initial manuscript. The user study in the thesisreceived approval from the Behavioural Research Ethics Board (BREB) at UBC:H22-00086.Versions of Chapter 4 of this thesis have either been submitted to, or are beingprepared for submission to, peer-reviewed international conferences.• Mokhberi, A., Huang, Y., Humbert, G., Mehrabi Koushki, M., Obada-Obieh,B. & Beznosov, K. Trust, Privacy, and Safety Factors Associated with Deci-sion Making in Social Network-Based P2P Markets: A Case Study of Face-book Marketplace.• Mokhberi, A., Humbert, G. & Beznosov, K. “I’m bringing my dog:” Trust,Privacy, and Safety Strategies on FM Trading.viTable of ContentsAbstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiiLay Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vPreface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viTable of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viiList of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xList of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiAcknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.2 Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51.3 Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 Background and Related Work . . . . . . . . . . . . . . . . . . . . . 72.1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72.1.1 Trust . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72.1.2 Privacy . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.1.3 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82.1.4 S-Commerce . . . . . . . . . . . . . . . . . . . . . . . . 92.1.5 FM-Like Platforms . . . . . . . . . . . . . . . . . . . . . 9vii2.2 Facebook Marketplace (FM) . . . . . . . . . . . . . . . . . . . . 92.2.1 P2P Trading Steps on FM . . . . . . . . . . . . . . . . . 92.2.2 FM and TPS Aspects . . . . . . . . . . . . . . . . . . . . 122.3 Literature Review . . . . . . . . . . . . . . . . . . . . . . . . . . 142.3.1 Information Sharing on P2P Marketplaces . . . . . . . . . 142.3.2 Commerce Features and TPS Aspects . . . . . . . . . . . 162.3.3 S-Commerce and TPS Aspects . . . . . . . . . . . . . . . 173 Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193.1 Data Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . 203.2 Interview Procedure . . . . . . . . . . . . . . . . . . . . . . . . . 213.3 Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213.4 Participants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233.5 Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254.1 TPS-Related Factors Influencing Decision Making . . . . . . . . 254.1.1 Pre-Existing Concerns . . . . . . . . . . . . . . . . . . . 274.1.2 Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . 324.1.3 Social Norms . . . . . . . . . . . . . . . . . . . . . . . . 394.1.4 Perceived Benefits . . . . . . . . . . . . . . . . . . . . . 404.1.5 Platform Design . . . . . . . . . . . . . . . . . . . . . . 424.2 TPS-Related Strategies . . . . . . . . . . . . . . . . . . . . . . . 434.2.1 Trader Selection and Screening . . . . . . . . . . . . . . 444.2.2 Information Collection and Sharing . . . . . . . . . . . . 484.2.3 Negotiation of In-Person Trading Details . . . . . . . . . 514.2.4 In-Person Interaction . . . . . . . . . . . . . . . . . . . . 545 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 585.1 Tension: Privacy vs. Trust . . . . . . . . . . . . . . . . . . . . . 595.2 Tension: Using vs. Abusing FM Features . . . . . . . . . . . . . 615.3 Tension: Warning vs. Reassuring Signals . . . . . . . . . . . . . 635.4 Challenge: Information Sharing Aspects of Entangling FM with FB 645.5 Challenge: Complexity of the Decision-Making Process . . . . . 65viii5.6 Discrepancy: TPS Strategies of Users vs. Police/FM . . . . . . . 675.7 Trade-Off: Developing vs. Influencing Factors . . . . . . . . . . . 686 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74A Supporting Materials . . . . . . . . . . . . . . . . . . . . . . . . . . 89ixList of TablesTable 2.1 Comparing FM to Other Popular P2P Marketplaces. . . . . . . 14Table 3.1 Participant Demographics Summary, NG: Not Given. . . . . . 23Table 5.1 Table of Strategies: This Table Illustrates Strategies Used byParticipants, Strategies Recommended by FM, and StrategiesRecommended by the Police. . . . . . . . . . . . . . . . . . . 71xList of FiguresFigure 2.1 The Buyer’s View of the FM Platform’s Initial Page: Cate-gories and Features to Assist with Item Selection. . . . . . . . 10Figure 2.2 The E-Commerce Landscape and the Position of FM within it. 11Figure 2.3 Step-by-Step Process for Trading on FM Platform: Engaging,Communicating, Meeting, and Following-up . . . . . . . . . 12Figure 2.4 Components of FM Seller Profile: (1) Item Listing Screenshot,(2) Commerce Profile Page, (3) Seller Rating Information, and(4) Publicly Accessible Facebook Profile. . . . . . . . . . . . 13Figure 3.1 Saturation Graph: Total Number of Codes Generated after EachInterview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24Figure 4.1 Demographic Distribution of Sample, NG: Not Given . . . . . 26Figure 4.2 Demographic Distribution of Sample, NG: Not Given . . . . . 27Figure 4.3 Framework of TPS-Related Factors on FM: Categorized intoThree Main Themes (Hinder, Promote, and Influence Priorityof TPS), Five Groups of Factors (Pre-existing Concerns, Sig-nals, Social Norms, Perceived Benefits, and Platform Design)and Factors. Each Factor Includes a Gray Circle that Indicatesits Relation to Trust, Privacy, and/or Safety. T: Trust, P: Pri-vacy, and S: Safety . . . . . . . . . . . . . . . . . . . . . . . 28Figure 4.4 Alignment of Participant Strategies with the User Journey onFM: A Visual Representation . . . . . . . . . . . . . . . . . . 44xiFigure 4.5 Framework of TPS-Related Strategies on FM: Main StrategiesPresented with Gray Background and Subcategories in White. 45xiiAcknowledgmentsI wish to extend my heartfelt gratitude to the individuals who have contributedto the completion of this thesis. First and foremost, I express my appreciationto my supervisor, Professor Konstantin Beznosov, for his valuable feedback andguidance throughout my research. I am also grateful to Professor Dongwook Yoonand Professor Karthik Pattabiraman for their insightful comments and willingnessto serve on my committee. I would like to especially thank Professor MohammadShahrad for his insightful discussions about computer engineering aspects, whichgreatly improved my understanding of the topic. Finally, I extend my thanks toProfessor Lutz Lampe and Erica Triggs for their valuable assistance.I would like to express my gratitude to my colleagues at the LERSSE lab, YueHuang, Masoud Mehrabi Koushki, Borke Obada, and Artemij Voskobojnikov, fortheir valuable feedback and constructive discussions during my studies. I extendmy gratitude to Guillaume Humbert, the visiting student from France, for his ex-cellent contribution to this project. I am deeply indebted to the 42 participants whogenerously shared their time and experiences, without whom this study would nothave been possible. I am deeply grateful to all of my dear friends for their constantsupport and encouragement.Last but definitely not least, I would like to express my profound gratitude tomy parents, Mina and Saeed, for their boundless love, unwavering support, andconsistent encouragement throughout my academic journey. I am deeply thankfulfor their belief in me, which has provided me with the confidence to aim higher andstrive for excellence. I am deeply grateful to my sisters, Arezoo and Adele, andbrother-in-law, Tom, for their boundless support and love. Thank you for inspiringme to strive for a better version of myself.xiiiChapter 1IntroductionA peer-to-peer (P2P) S-commerce platform, Facebook Marketplace (FM), is be-coming very popular. Introduced as recently as 2016, FM is already available in150 countries and territories [140] and is one of the largest S-commence platforms,with over one billion visitors per month and growing [7]. With FM, both peopleand businesses can list items for sale, whether they are used items or brand-newproducts [8]. Since it is tightly entangled with Facebook, the largest social networkin the world (with 2.96 billion monthly active users as of December 31, 2022 [2]),adoption of FM will likely keep increasing. In this thesis, we look at FM tradersamong just people. For readers who may not be familiar with the user experienceof FM, we recommend referring to Chapter 2 for comprehensive descriptions andvisual representations of the interfaces.FM is at the intersection of S-commerce and P2P marketplaces. Marketplacessuch as FM are at the intersection of S-commerce and P2P commerce, two emerg-ing digital business models that are transforming the way businesses operate in the21st century [32, 47, 95, 122]. S-commerce, also known as social commerce, refersto the use of social network to facilitate transactions. Peer-to-peer commerce is atype of online retailing that allows individuals to buy and sell products and servicesdirectly to one another without the use of a middleman. By combining these twomodels, FM-like marketplaces allow buyers and sellers to interact directly witheach other and complete transactions without the need for a third party. This al-lows buyers and sellers to take advantage of the convenience and low cost of online1shopping while still maintaining the trust and personal connections that are foundin traditional marketplaces.While platforms like FM are becoming popular, they raise various trust, pri-vacy, and safety concerns for users. Essential for online transactions betweenstrangers, trust is a fundamental requirement for S-commerce platforms [58, 65],especially when the transactions involve disclosing personal information [138].Therefore, trust management is identified as one of the biggest challenges for S-commerce users [26, 27, 42, 62, 80, 81, 121]. In addition to trust issues, the useof social network platforms (i.e., Facebook) impose privacy issues for users, dueto the disclosure of personal information [90]. Safety is another challenging as-pect for p2p marketplace users. For instance, users of FM face safety risks [3, 54],including scams [21, 145],1 fraud [18, 145], and even murder [136].S-commerce and P2P marketplaces have been studied separately for how trust,privacy, and safety aspects influence the decisions and actions made by users.Numerous studies investigated information sharing, intention to purchase, trust,safety, and perception of privacy risks on S-commerce platforms [39, 42, 62, 80,81, 98, 99, 111, 121]. Prior studies focused on investigating how people buildtrust on P2P marketplaces [52, 53, 59, 93, 143] and on S-commerce platforms,such as FB groups [42, 62, 80, 81, 121], Instagram [26, 27], Craigslist [111],and VarageSale [111]. For instance, researchers discovered that being in a closegroup [81, 121], having similarities with the traders [81], and close proximity [81]influence trust-related decision making on FB groups. In P2P marketplaces, peopleshare personal information to build trust [52, 53, 59]. Researchers also found usershave concerns about safety in trading on S-commerce platforms [61, 121]. Whilethere are studies related to different types of S-commerce and P2P platforms, a re-search gap exists in S-commerce studies regarding how TPS factors influence FMusers’ decisions.FM is quite different from previously studied platforms. The unique qualitiesof FM make it different from other E-commerce, S-commerce, and P2P market-place platforms in five ways. First, unlike older E-commerce platforms, such aseBay and Amazon, it does not provide conventional trust assurance mechanisms,1In 2022, a report suggested that one in six users reported experiencing scams on FM [145].2such as conflict resolution systems, escrow payment services, and consumer pro-tection programs that offer money-back guarantees [121] for their users. Second,some other trust measures on other S-commerce platforms (e.g., WhatsApp groupsand Instagram), such as friend and family suggestions [26], are not available toFM users either. Third, not only does FM platform refrain from intervening inthe exchange of goods and money, but also, unlike Facebook (FB) buy-and-sellgroups [61], it lacks human administrators who would moderate the group or en-force rules. Forth, unlike FB buy-and-sell groups, which require group administra-tors’ permission to join, to start using FM, one needs only an FB account and beof majority age [10]. Finally, unlike anonymous marketplaces, such as Craigslist,2that allow anonymous postings, FM links every for-sale post to an individual’s FBprofile [112].Our next section, Section 1.1, presents an overview of our research, followedby Section 1.2, which summarizes our contributions. In Section 1.3, the thesis’structure is outlined.1.1 OverviewOur study fills the research gap regarding users’ TPS factors and strategies for trad-ing on FM, which differ from previously studied platforms. In this study, we ad-dress the lack of understanding of what TPS factors users take into account whenmaking decisions, and what TPS strategies they take to trade on FM, a popularE-commerce platform that has over one billion users. Studying the factors that in-fluence TPS decision-making and the TPS strategies of users is essential for betterunderstanding their TPS management. Furthermore, this thesis demonstrates thedistinctiveness of FM and the insufficient comprehension of how users arrive atTPS-related decisions and what their TPS-related approaches entail.To this end, we conducted semi-structured 1-on-1 interviews with 42 partici-pants from North America who had trading experiences on FM. The aim was toexamine the TPS-related factors they considered while trading on FM, the chal-lenges they faced, their positive and negative experiences on FM, and the concernsthey had about trading on FM. Data gathering and analyses resulted in the develop-2https://www.craigslist.org/about/sites3ment of two distinct frameworks. The first framework categorizes the factors intothree major themes: hindering or promoting the development of TPS, and influ-encing the priority of TPS. For each theme, we also list the main groups of factors,including pre-existing concerns, signals, social norms, perceived benefits, and plat-form design. The thirteen factors in this diagram include online risks, offline risks,trader’s behavior, Facebook profile, FM profile, Facebook support, perceived trust-worthiness, trading unwritten rules, financial gain, convenience, personal interests,platform usability, and platform popularity. The second framework categorizesstrategies into four main areas: trader selection and screening, information collec-tion and sharing, negotiation of in-person trading details, and in-person interac-tion. These strategies include using tools, watching conversations, selecting spe-cific groups for trading, avoiding transactions, accepting risks and doing the trans-action, sharing more information, gathering information about the item, reviewinginformation, gathering evidence, informing others about the meet-up, managingcontact information sharing, choosing specific payment methods, discussing meet-up aspects, meeting in specific spots, alerting the other trader, carrying safeguardtools, having a companion, finishing the trade before leaving, providing support,and acting asymmetrically when they are the buyer versus the seller.User decisions, including their preferred payment methods, willingness to meetwith other users in person, and the extent to which they are willing to share per-sonal information, significantly influence their strategies for protecting their trust,privacy, and safety (TPS) when using e-commerce platforms such as FM. Thesefindings have important implications for improving the experience of FM users andassisting them in managing TPS-related risks. Specifically, the results of this studycan inform the design of FM and similar platforms, providing guidance on how tobetter support users and enhance their experience by improving their protection inthese digital marketplaces. Additionally, these findings may help researchers iden-tify potential areas for future investigation aimed at improving users’ TPS-relateddecision-making while trading on FM. Finally, the results of this study can also bebeneficial for future social network platforms that include a marketplace, as theycan use this information to develop better TPS-related support for their users.41.2 ContributionsThe following is a summary of our contributions to the user studies we conducted:First, this study demonstrates the TPS-related factors that inform users’ deci-sions on whether they want to engage in a specific trade with a particular seller orbuyer. The framework contains three layers: the theme (hindering, promoting, in-fluencing priority) and five groups of factors (pre-existing concerns, signals, socialnorms, perceived benefits, and platform design).Second, this study illustrates the TPS-related strategies taken by FM users.The framework includes four types of strategies: trader selection and screening,information collection and sharing, negotiation of in-person trading details, andin-person interaction.Third, we identified the tension between privacy protection and trust building,using and abusing FM features, and warning and reassuring signals. Further, wediscuss challenges arising from entangling a marketplace with a social networksite, and the complexity of the decision-making process for FM users. Throughour analysis, we found trade-offs that arise from the interplay between factors thatdevelop TPS and factors that influence TPS in decision-making, as well as discrep-ancies regarding managing TPS aspects.Finally, our study proposed a set of recommendations for future studies basedon our developed frameworks. We identified several research gaps that could beaddressed in order to further understand and design social network-based market-places, such as FM. For example, our study revealed a need for more research intohow to redesign the TPS-related features to prevent the abuse of these features andprovide better support for users. Additionally, we identified the need for futurestudy of the impact of transparency and feedback from the platforms to the users,to support users in building trust both toward the platform itself and toward otherusers. We proposed that future studies should focus on studying the heterogeneityof users in terms of TPS in more depth to be able to improve systems in a way thatthey could be inclusive, based on the diversity of needs of different types of users.1.3 OutlineThis thesis is organized as follows.51. In Chapter 2, we provide definitions, background information, and relatedwork for this thesis. It includes related studies in the areas of P2P marketplaces,S-commerce and TPS aspects, and features and TPS-related decision making.2. In Chapter 3, we present the methodology that we used in order to conductthis study. The qualitative data collected from FM users was based on a human-centered approach.3. In Chapter 4, we present the results of our research, based on the two frame-works that we developed. TPS-related factors and strategies are discussed in twosections.4. In Chapter 5, the contributions of this thesis are summarized, and futuredirections are introduced.6Chapter 2Background and Related Work2.1 DefinitionsThis section includes our definitions for privacy, trust, safety, S-commerce, andFM-like platforms on which we will rely to analyze/categorize our data and com-pare our findings to the existing literature.2.1.1 TrustTrust has been a topic of research in various fields such as psychology, sociology,and economics. The focus of previous psychological studies on trust has beenon individual traits, while sociological studies have emphasized the institutionalaspects of trust [99]. In economics, trust has been studied from two perspectives- trust as an expectation of interactions and trust related to vulnerability exposureand acceptance [99]. The definition of trust has been shaped by researchers fromdiverse fields, resulting in various interpretations [99].We have adopted a specific definition of trust because trust plays a critical rolein consumers’ decisions to purchase items online. This trust is not only betweentraders but also between consumers and the computer system that facilitates thetransaction [34]. Although various definitions of trust encompass the idea of risk-taking, most of them are simply adaptations of traditional marketing literature anddo not adequately reflect the online context. Our chosen definition will enableus to examine the relationships between trustworthiness, privacy, and safety more7effectively. In essence, we define trust as a buyer/seller’s subjective belief that theother party or platform will meet their expectations or promises.2.1.2 PrivacyDefining privacy has always been challenging. Some philosophers have attemptedto define privacy as accessibility to an individual, while others have seen it as beingleft alone [107]. The notion of being left alone was adopted by Samuel Warren andLouis Brandeis in their 1890 Harvard Law Review article, and it is still influen-tial [107]. Some people define privacy in terms of controlling personal informationor matters, while others view it in terms of values such as intimacy, social relation-ships, etc [107].When defining privacy for this study, two aspects need to be considered. Firstly,the nature of FM, which is a social network-based marketplace where users sharevarious information for different purposes, requires a specific definition of privacyto be adopted. Secondly, it’s important to acknowledge that the control of data isnot solely in the hands of users, but also in the hands of the FM platform. We definea seller/buyer’s privacy as the control that a seller or buyer has over the informationthey share with the platform and other traders, and how this information is used bythe platform and other traders during and/or after the transaction.2.1.3 SafetyIn this study, safety refers to the protection of users both online and offline. Onlinesafety encompasses measures to safeguard individuals from cyber threats [102],such as hacking and scamming, while offline safety refers to physical safety, in-cluding protection from violence and harm incidents. Moreover, safety in thiscontext also incorporates the psychological and emotional well-being of individu-als, such as protecting them from online harassment or bullying, which can havean impact on mental health [129]. Overall, the study focuses on a comprehensiveapproach to safety, encompassing different aspects of human safety. We define aseller/buyer’s safety as their confidence that they will be safe from physical injury,emotional harm, loss of financial assets, and loss of physical assets.82.1.4 S-CommerceWe use Wang’s definition of S-commerce as “a form of commerce that is mediatedby social network” and uses social network sites to “support social interactionsand user contributions to assist activities in the buying and selling of products andservices online and offline” [151, P. 2]There are three types of social commerce platforms (1)companies’ e-commercewebsites that add web 2.0 features; such as Amazon [46]; (2) social network plat-forms where companies have the possibility to create pages with different types ofcontent (e.g., video, photos) and add e-commerce features, such as Facebook witha company’s page such as Starbucks’ [83]; and (3) peer-to-peer marketplaces em-bedded in social network platforms, allowing individuals to trade with each other,such as FM. In this thesis, we investigated user experiences related to the third typeof S-commerce platforms listed here.2.1.5 FM-Like PlatformsA number of P2P marketplaces1 exist for trading second-hand items. We considera marketplace “FM-like” if it is not human-moderated, people are not anonymous,registration is open, and it is based on a social network platform. In table 2.1, weshowed some examples of such P2P marketplaces and how they are similar to ordifferent from FM.2.2 Facebook Marketplace (FM)As mentioned in the introductory section, FM lies at the crossroads of S-commerceand P2P marketplaces. In Figure 2.2, the location of FM among other platformswas presented.2.2.1 P2P Trading Steps on FMFM is an online marketplace where Facebook users can buy and sell items fromeach other [12]. It is available to anyone who has a Facebook account, allowing1“A Peer-to-peer (P2P) marketplace is a decentralized model whereby two individuals interactto buy and sell goods and services directly with each other or produce goods and service together,without an intermediary third party or the use of an incorporated entity or business firm.” [1]9Figure 2.1: The Buyer’s View of the FM Platform’s Initial Page: Categoriesand Features to Assist with Item Selection.them to search for items in their local area or around the world [12]. On FM, userscan post items for sale, search for items they want to buy, and communicate withother users to arrange payment or delivery. The items that users can list on Market-place range from electronics, furniture, apparel, and other goods. It is important tonote that users are not allowed to post services, tickets, or animals on Marketplace.Additionally, FM provided a list of items and activities prohibited or restricted onFM [9]. For instance, users are not allowed to list items that are prohibited by law,or items that are counterfeit or stolen.In this section, we will provide a breakdown of the steps involved in the journeyof FM users on P2P trading on FM-like platforms, which is illustrated in Figure 2.3.The process consists of the following stages:STEP 1: Engage with the PlatformSeller:• Engage with the platform by creating a post for the item you want to sell.Ensure they include a detailed description, photos, and price.Buyer:10Figure 2.2: The E-Commerce Landscape and the Position of FM within it.• Engage with the platform by using the search bar or browsing categories tofind the item they are looking for.STEP 2: Negotiate VirtuallySeller:• Potential buyers will contact sellers through messages with offers or ques-tions. Once they’ve found a buyer that meets their criteria, agree to the termsof the purchase.Buyer:• Message the seller with questions about the item or to arrange a time to meetup.• Once they’ve found an item and seller that meet your criteria, agree to theterms of the purchase.STEP 3: Meet in Person11Buyer/Seller:• Arrange a meeting to complete the transaction.• Exchange money and item and potentially evaluate the item.STEP 4: Follow-up After TradingBuyer/Seller:• After the transaction is complete, leave feedback for the buyer and sellerabout the experience.• Communicate if needed the issues with the payment or item.Figure 2.3: Step-by-Step Process for Trading on FM Platform: Engaging,Communicating, Meeting, and Following-upFigure 2.1 depicts the buyer’s view of the FM platform’s initial page, illustrat-ing the categories and features available to assist with item selection. On the otherhand, Figure 2.4 presents the components of an FM seller profile, which include ascreenshot of an item listing, a commerce profile page, seller rating information,and a publicly accessible Facebook profile. All of these components were recordedbetween February and June of 2022.2.2.2 FM and TPS AspectsFM, specifically, provides more personal information as it is based on FB socialnetwork, which could be a double-edged sword. Traders can see other traders’ FB12Figure 2.4: Components of FM Seller Profile: (1) Item Listing Screenshot,(2) Commerce Profile Page, (3) Seller Rating Information, and (4) Pub-licly Accessible Facebook Profile.13HumanmoderatorAnonymoususersOpenaccessSocialnetwork-basedTwo-sidedFM No No Yes Yes YesNextdoor [13] No No Yes Yes YesVaragsale [149] No No Yes No YesOfferUp [14] No No Yes No YesCraigslist [6] No Yes Yes No YesKijiji [11] No Yes Yes No YesBuy-sellgroups on FBYes No No Yes YesInstagrampagesYes No Yes Yes NoTable 2.1: Comparing FM to Other Popular P2P Marketplaces.accounts and can access their personal information that is not necessary for trad-ing purposes, such as other traders’ personal details (e.g., marital state), interests,activities, shared contents, or locations. Such personal information can help usersto generate a greater sense of personal connection with other users and to facilitateidentification verification [59]. Users of FB have been shown to depend heavilyon profile pictures when assessing the personal information of other users [87].On the other hand, the disclosure of information may cause issues, such as loss ofprivacy, as information may be misused outside of one’s control and its intendedcontext [115] and might cause harm to marginalized groups [59, 111].2.3 Literature ReviewWhile FM is an S-commerce P2P marketplace, we use the rest of this section todiscuss previous studies about information sharing on P2P marketplace, followedby a review of reports of TPS issues on S-commerce platforms.2.3.1 Information Sharing on P2P MarketplacesPersonal information shared in P2P marketplaces is the main source for buildingtrust. P2P marketplaces have developed with different aims, such as finding ac-14commodation (e.g., Airbnb), car-riding (e.g., Uber), and second-hand goods (e.g.,FM). How users build trust in such platforms has received considerable atten-tion. Much work has been done to evaluate the factors associated with trust build-ing [35, 37, 59, 75, 76, 105, 117–119, 127] as it is a keystone in behavior and deci-sion making for users of such platforms. Once trust is established, formal contractscould be replaced to make transactions safer and more efficient [48]. Studies foundthree types of trust needed: trust toward technology, the platform, and the othertraders [37, 70, 97]. Users also have concerns about information sharing. People’swillingness to share information differed based on the information sharees [128]and is influenced by their privacy concerns [91].Personal information such as names and photos influence the sense of trust [52,52, 53, 59, 93, 143]. For example, it has been reported that African American hostsface a higher pricing penalty for having a bad location score [53]. Being a woman,or of older age, actually increases the sense of trust [57, 94] for renters. Similarly,the number of persons in a user’s profile photo may influence the possibility of ac-ceptance, with couples having the best chances, followed by guests who are shownalone [57]. For example, Ert et al., investigated the role of photos and showedthat the perceived trustworthiness of Airbnb hosts is directly associated with fa-cial traits in profile pictures, such as age, gender, and smile [57]. Reputation andvisual-based trust2 are other factors that might influence potential buyers [59].Different studies showed information provided on P2P platforms might causediscrimination. Previous studies have found that people were discriminated againstbased on their ethnicity, gender, age, or other characteristics [53, 59, 111, 143,144]. For instance, in the cases of car-riding apps such as Uber and Lyft, AfricanAmerican passengers wait longer and are more likely to be rejected by their driversthan those with white-sounding names [66]. Further, female passengers were takenon longer, more expensive rides3 [66].2“consumers infer sellers’ trustworthiness from their photos” [59, p. 63]3It is possible that the driver spends more time searching for the passenger despite arriving forthe pickup in the same amount of time. This might explain why there was a longer travel time forUberX, even though the distance was not longer [66].152.3.2 Commerce Features and TPS AspectsAs discussed, trust is the fundamental stone for trading in online platforms. To thisend, platforms provide different tools and support for users to facilitate trust andprotect their privacy and safety.One such tool is assurance mechanisms to assist users in safe trading. WhileFM has some of the essential trust assurance mechanisms, such as feedback andreputation systems [33, 135], it lacks other trust assurances, such as conflict reso-lution systems, fraud detection, escrow payment services, and consumer protectionprograms that offer money-back guarantees.Another strategy for providing user support is through the implementation ofsocial commerce features. Prior research in S-commerce and E-commerce sug-gests that rating and reviewing positively facilitate users’ decision making [25, 31,40, 96, 97, 132]. For example, Alalwan et al. [25] found that social trust will bepositively affected by reviews and ratings. Pavlou et al. found that text commentswith rich content play important roles in building buyers’ trust in the benevolenceand credibility of a seller [131].Studies have investigated the role of ratings, reviews, and comments on thepurchase of products on commerce platforms, finding that higher numerical ratings,more reviews, and positive sentiment can signal a higher-quality product and affectsales. Various studies investigated the role of rating, reviewing, and commenting onthe purchase of products on commerce platforms [78, 82, 100, 110]. For instance,it is possible to interpret a high numerical rating or a large number of reviews as asignal of a high-quality product [78]. Customers’ choice behavior can be directlyinfluenced by the volume, valence, and sentiment of online reviews. There is ahigher probability of making a choice when valence is higher, measured by a higheraverage star rating [100]. In another study, Hu et al. [82] found that ratings did nothave a significant impact on sales directly, but can indirectly affect them throughsentiments. Sales, however, are directly affected by sentiment. All of these ratingsystems are related to the rating of the products or the company.162.3.3 S-Commerce and TPS AspectsResearchers investigated the trust aspects of many S-commerce platforms, but FM.Several scholars have investigated trust challenges related to the commercial as-pects of social network platforms such as FB groups [42, 62, 80, 81, 121], In-stagram [26, 27], and Craigslist and VarageSale [111]. For instance, Moser etal. [121] conducted a study of a mom-to-mom sales group on FB with high-trustenvironments in the United States. They reported that feeling safe and trusted is animportant factor in users’ decisions. In such groups, trust is fostered by member-ship in an exclusive group, shared identity or perception of similarity among themembers of a group, and regulation and sanctioning of behavior at the levels of theadministrator, member, and group. Similarly, Hsiao et al. [81] examined FB groupsin the U.S. for newcomers and found that trust was influenced by the followingcomponents of shared identity: close geographical proximity, similar life stages,similar ethnic backgrounds, and similar lifestyles and socioeconomic status. Evanset al. [61] investigated FB groups in Venezuela to understand a solidarity econ-omy alternative in an environment of low trust. They discovered personal safetyconcerns within the FB group, such as threats of robbery, price-gouging, physicalharm, cancellation of trades, and alterations to products. In order to protect safety,users reviewed their profiles thoroughly, met up in public, only traded with women,and never attended a trade alone. Low-trust environments amplified the negativeaspects of FB group P2P interactions, such as fear of being scammed [121]. Lin-gel [111] reported some differences between Craigslist and VarageSale based ona user study. Female participants perceived FB groups to be safer than Craigslist.Participants thought that anonymity would put them at a higher risk of harm be-cause they did not know who they were talking to [111]. Habib et al., [71] inves-tigated user needs for advertising controls on Facebook. They found that there isa need to give users the option of selecting ad topics or personal information thatis used in ad targeting. There is also a lack of awareness about available privacyoptions, as well as problems with usability (location, layout, and explanation ofcontrols).In the present thesis, we aim to extend the existing knowledge on the topic anddelve into the intricacies of how FM users navigate the various aspects of TPS.17Specifically, we explore the role of information sharing, feature utilization, andinteraction with strangers in the management of TPS.18Chapter 3MethodologyIn this study, a human-centered approach was employed to investigate researchquestions pertaining to the topic. Specifically, a qualitative study was conducted,which included semi-structured interviews to explore the research questions. Theprimary aim of this study was to gain a comprehensive understanding of TPS-related management aspects among FM users and to explore the diverse perspec-tives and experiences of the participants involved.The study was comprised of three research questions:(1) what are the trust, privacy, and safety factors associated with purchasing orselling used items on FM?(2) what factors influence the priorities of trust, privacy, and safety for FMusers?(3) what are the trust, privacy, and safety strategies used by participants?Semi-structured 1-on-1 interviews were conducted with recruited participantsto facilitate the free expression of thoughts and the addition of information withoutbeing restricted by a structured interview format, as suggested by Cohen [44]. Atotal of 42 interviews were conducted through the use of Zoom. Before data col-lection commenced, the research received ethic approval from the university ethicscommittee (ID: H22-00086).193.1 Data CollectionOur pilot study, combined with various methods of recruitment, enabled us to col-lect data for our study. To ensure the effectiveness of our study procedure, wepiloted it with three participants. After reviewing the feedback from the pilot inter-views, we revised the interview questions to enhance clarity and re-ordered them tofacilitate a more fluent and effective recall of participants’ memories of using theFM. No changes were made to the other instruments used in the main study fromthose used in the pilot study. We recruited participants through various means,including advertising on Facebook paid ads, posting on our university’s paid par-ticipant study list, and utilizing snowball sampling by asking participants to sharethe link of our study with their friends or family members who faced issues withFM.Participants were selected based on the inclusion and exclusion criteria of thestudy. We used a screening questionnaire to find a suitable and diverse sample ofparticipants. To be eligible to participate in the study, participants had to be at least19 years of age, reside in the United States or Canada, and have had trading ex-periences on FM. 941 responses were received. We selected interview participantsfrom this pool based on the diversity of the sample and the participant’s potentialexperience with or knowledge of FM to help us in developing the framework. Forthe sampling, we achieved diversity by inviting participants who indicated (1) dif-ferent experiences in using P2P marketplaces for goods (e.g., amount of experienceusing P2P marketplaces, FM-use per year, pleasant and unpleasant experienceswith FM, diversity of experiences with the items they bought and whether theywere seller or buyer or both on FM); (2) demographic groups (e.g., race, gender,age, education, and job type), (3) life situation (e.g., the place they live, size of thecity, years being in the country), and (4) socioeconomic level (e.g., income levelper year, ranging from marginalized groups to privileged groups). This diversitycould help me to mitigate potential biases toward a specific gender, age range, etc.The participants were compensated with $20 via e-transfer or Amazon gift cards.Data collection took place between February to July 2022.203.2 Interview ProcedureThe semi-structured interview was designed to understand the participants’ indi-vidual perspectives on the research topic. After the participants provided informedconsent to participate in the study, we conducted the interviews, which took an av-erage of one hour. During each interview, participants were asked questions abouttheir experiences using FM. We started with questions about why they began us-ing FM, and its advantages and disadvantages in comparison with other similarplatforms. Next, participants were asked to describe their experiences of buyingand selling products on FM, their most pleasant and unpleasant experiences, whatmade those experiences pleasant or unpleasant, and their experience in using FMfeatures. Last, We asked about payment methods, meet-ups, and interactions re-garding their past trades.Participants brought up the topics of trust, privacy, and safety, without priming,which we further explored in-depth. We avoided priming the participants by notasking direct questions related to TPS. We stated that the purpose of the study wasto gain insight into their experiences with FM. The words trust, privacy, and safetywere brought up by our participants, and we asked follow-up questions to find outmore about their reasons for TPS-related concerns, and the factors that influencetheir TPS decisions. We found that for many participants, FM usage is significantlyintertwined with concerns of privacy and safety, and that TPS factors often overlap.Interview questions can be seen in the Appendix A.3.3 Data AnalysisAll of the data gathered in the qualitative study was analyzed thematically to an-swer the research questions. All interview sessions were audio-recorded and tran-scribed for data analysis. We followed the steps of thematic analyses [126, 148] inanalyzing data and developing a framework. The data collection and data analysiswas an iterative process [126, 148]. We Used the data analysis steps outlined byGuest et al. [69]. We developed a codebook. The codebook was developed basedon the segmentation and coding of transcribed interviews. In total, we extracted737 codes. The data was then analyzed by three researchers in order to identifythemes that emerged. To obtain consensus on the identified themes, six researchers21engaged in a code and theme sorting exercise. We identified the main factors andsubfactors in three themes (Figure 4.3). We reached theoretical saturation after 42interviews, as no new codes were identified [68] in the last three rounds of datacollection (see the graph 3.4).223.4 ParticipantsWe recruited 42 participants (22 women, 19 men, and 1 non-self-identified), aged19 to 75 years (the mean and median were 32). Table 3.1 provides the detaileddemographics of the participants.P# Age Gender Ethnicity Location Occupation Education level Income level (CAD$) FM usageP01 24 F African American Vancouver/CA Receptionist Bachelor 50k∼75k 1-2d/weekP02 70 M White Vancouver/CA Retired Master 100k∼150k NGP03 37 F South Asian Toronto/CA Arts administrator Master 25k∼50k 1-2d/monthP04 75 F East & Southeast Asian Vancouver/CA Retired Master 25k∼50k 1-2d/yearP05 28 M South Asian Calgery/CA Software developer Bachelor 75∼100 1-2d/monthP06 29 F East & Southeast Asian Vancouver/CA Educator Bachelor 75k∼100k 1-2d/weekP07 19 M South Asian Edmonton/CA Student High school 1k∼10k 1-2d/weekP08 50 F White High Point/US Social worker Master 50k∼75k 1-2d/yearP09 40 F African American Charleston/US Teacher Bachelor 25k∼50k 3-5d/weekP10 44 M White Regina/CA Teacher Master 100k∼150k Every dayP11 36 M African American New York/US NG Master 100k∼150k Every dayP12 33 M Middle East Edmonton/CA Journal editor Doctorate 75k∼100k 1-2/weekP13 26 F East & Southeast Asian Vancouver/CA UX designer Bachelor 50k∼75k NGP14 19 F East & Southeast Asian Vancouver/CA Student High School 0 1-2d/monthP15 22 F White Toronto/CA Consultant Bachelor 25k∼50k 1-2d/yearP16 29 NG East & Southeast Asian Vancouver/CA Artist Master 50k∼75k 3-5d/weekP17 31 M East & Southeast Asian Vancouver/CA Operations analyst Master 50k∼75k 1-2d/monthP18 68 F White Churchill/CA NG Master 50k∼75k Every dayP19 45 F White Toronto/CA Administrator High school 25k∼50k Every dayP20 67 F White Tucson/US Airbnb Host Bachelor 10k∼25k 1-2d/weekP21 43 F Indigenous Stonewall/CA Program developer Bachelor 25k∼50k 1-2d/yearP22 51 F Hispanic Chicago/US Office receptionist High school 50k∼75k Many times/weekP23 44 F White Summer field/US Book keeper Bachelor 75k∼100k 1-2d/monthP24 28 F African American houston/US Registered nurses Bachelor 50k∼75k 1-2d/monthP25 22 F South Asian Surrey/CA Student Bachelor 1k∼10k Many times/weekP26 50 F White Menasha/US Guest preacher Master 10k∼25k 1-2d/weekP27 19 F White Aurora/CA Student High school 0 1-2d/yearP28 59 M White Haysville/US Machinist College 25k∼50k EverydayP29 35 F South Asian Waterloo/CA Graduate student Master 25k∼50k 1-2d/monthP30 20 F South Asian Kelowna/CA Student Bachelor NG 1-2d/monthP31 19 M East & Southeast Asian Vancouver/CA Student High school 1k∼10k 1-2d/yearP32 40 F White Vinton/US Homemaker High school 1k∼10k EverydayP33 23 M East & Southeast Asian Toronto/CA store front Bachelor 25k∼50k 1-2d/weekP34 22 M White Richmond/CA Student Bachelor 1k∼10k 1-2d/monthP35 27 M South Asian Burnaby/CA Accountant Bachelor NG 1-2d/weekP36 29 M White Rochester hills/US NG High school 1k∼10k 1-2d/monthP37 20 M East & Southeast Asian Vancouver/CA student Bachelor 1k∼10k many times/weekP38 28 M South Asian Vancouver/CA student Master 10k∼25k many times/weekP39 26 M White Montreal/CA Intervention worker Bachelor 25k∼50k many times/weekP40 48 M White Philadelphia /US Operations supervisor Bachelor 50k∼75k many times/weekP41 35 M White Grand Rapids /US Nurse Master 75k∼100k many times/weekP42 65 M African American Baltimore/US Retired College 25k∼50k 1-2d/yearTable 3.1: Participant Demographics Summary, NG: Not Given.3.5 LimitationsThis study has several limitations that should be taken into account when interpret-ing its results. First, we recruited participants from North America. Therefore, thisstudy may be subject to selection bias [45]. Second, in some of the interviews,participants explicitly explained why they had specific concerns, such as prior ex-perience or media news, but for some of the concerns, our participants had norational explanation. Due to the limitations of our method, we did not determine2310 20 30 400200400600800InterviewsTotalnumberofcodesFigure 3.1: Saturation Graph: Total Number of Codes Generated after EachInterview.which of them were grounded in the rationale or experience and which were not.It is possible that our findings may have been influenced by systematic biases [49],as with any qualitative research. To reduce researcher bias, multiple researchersanalyzed the data and reached a consensus on their interpretations [125, 130].24Chapter 4Results4.1 TPS-Related Factors Influencing Decision MakingWe conducted semi-structured interviews with 42 FM users from a diverse rangeof subjects. Participants came from a variety of age groups, ranging from 19 to75 years (median was 32 and mean was 36.7); genders (22 women, 19 men, and1 non-self-identified); ethnic backgrounds (Black, White, Asian, Indigenous, andHispanic); city sizes (from small cities such as Churchill to mega-cities such asNew York); occupations (e.g., student, teacher, artist, retired, nurse); educationallevels (high school, bachelor, master, college, and doctorate); income levels (rang-ing from $0 to $100K per year); and FM use frequencies (e.g., 1-2/year to everyday). Detailed demographics of the participants are provided in Table 3.1. Fig-ure 4.1 and Figure 4.2 demonstrate the diversity of the sample by presenting thedistribution of demographic information.Throughout this section, we report on our findings based on the framework offactors associated with the FM users’ TPS-related decision making. We catego-rized the identified factors into three major themes: hinder or promote the devel-opment of TPS, and influence the priority of TPS. For each theme, we also listthe main factors, including pre-existing concerns, signals, social norms, perceivedbenefits, and platform design. Eachgroup of factors, includes individual factors.As the illustration shows (Figure 4.3).25Figure 4.1: Demographic Distribution of Sample, NG: Not Given26Figure 4.2: Demographic Distribution of Sample, NG: Not Given4.1.1 Pre-Existing ConcernsIn this subsection, we report on the factors that hinder the development of TPS. By“pre-existing” we mean that these concerns are not related to any specific transac-27Figure 4.3: Framework of TPS-Related Factors on FM: Categorized intoThree Main Themes (Hinder, Promote, and Influence Priority of TPS),Five Groups of Factors (Pre-existing Concerns, Signals, Social Norms,Perceived Benefits, and Platform Design) and Factors. Each Factor In-cludes a Gray Circle that Indicates its Relation to Trust, Privacy, and/orSafety. T: Trust, P: Privacy, and S: Safetytion but pertain to P2P trading in general. Buyer/seller participants had concernsrelated to the risks of both online and offline trading on FM. These concerns mostlystem from the following factors: (1) what the participant had heard from friend-s/family about P2P marketplaces for goods; (2) the news they saw or heard aboutthese platforms; (3) social or cultural beliefs; and (4) negative past personal expe-28riences with P2P marketplaces; (5) negative past personal experiences, includingthose involving using FB in general and FM in particular.Online RisksInformation sharing and decision making were influenced by online concerns re-garding platforms and traders. Buyer/seller participants expressed concerns overprevious FB data breaches, the diversity of information collected by FB, the greaterharm associated with Facebook, the availability of social network features for themarketplace, and the abuse of FM features by traders. The first three concerns wererelated to the use of the FM platform itself, while the last two concerns involvedtrading with strangers.Familiarity with previous FB data breaches [38] raised trust and privacy con-cerns. Due to such concerns, participants switched to other platforms, changedtheir privacy settings, and/or avoided sharing personal information on FB-ownedapplications (e.g., WhatsApp). P17 said: “FB [is not] a company that, honestly,I have a lot of trust in ... I use [WhatsApp] but I just do not have a photo on myWhatsApp [profile] either. Because it is owned by the same company, I like to keepmy information, a little bit more hidden away from Mark Zuckerberg.”Participants expressed privacy and safety concerns regarding the wide range ofpersonal information that FB collects about them through a variety of services. AsFM is highly associated with FB and FB expanded its services (e.g., dating andmarketplaces), some participants believed that a broad range of their informationcould be gathered on FM. The perceived risks were related to the possibility ofabuse of these data by either the platform or FB users. P21 said: “... the moreinformation [FM] have the better [the] profile. They can sell these very accurateprofiles ... [and FM] can ... negotiate a higher rate for information.”Participants believed their privacy was inadequately protected on FM. Face-book was initially designed to facilitate connections between friends, like-mindedindividuals, and to provide a platform for sharing and receiving up-to-date news [50].Today, it remains a popular platform for connecting with friends, family members,and similar groups. As a social network, Facebook requires users to provide per-sonal information to make these types of connections. Subsequently, applications29such as FM were introduced to this platform. As such, participants perceived thatthe amount of information being shared on FM exceeded what was necessary forconducting a trade. The participants identified certain social network features, suchas the “friend request” option for traders, as a potential threat to privacy. For in-stance, one participant reported receiving a friend request from a stranger during atrading session, which made her feel uneasy as she did not wish to accept the re-quest at that time. As she was in the midst of trading, she perceived the request as aprivacy risk. Furthermore, she did not feel inclined to engage in friendship via FMas she did not know the person well. During the study, participants reported that alltraders had access to each other’s information on both FM and FB, even after thetrade had concluded. This means that traders could access personal information in-definitely, leading to the perception that a trader would be held responsible for theitem even after the sale was completed. This responsibility could include provid-ing technical support or addressing any defects in the item. As a result, participantsexpressed concern about potential privacy risks.At the same time, participants had concerns about the abuse of FM functionsintended to promote TPS. Participants were concerned that people with bad inten-tions might abuse blocking and reporting features to cut the access of the othertrader to themselves. P29-B described a related experience: “We got a TV. We weretrying to make sure that it was working. ... [She asked the sellers to connect it tothe internet, but seller] said: ’no! we don’t have Internet at home. ... Then wegot it home and realized that ... the TV Internet was not getting connected. Andthe remote was not working... [When she sent a message to the seller] the sellerblocked us ...”In contrast to other anonymous marketplaces, FM’s potential data breaches orscams have been considered more harmful. With FB credentials being used tologin to multiple platforms [56], participants had concerns that they would suffersignificant losses, if scammers gained access to FB credentials when participantsengaged in a trade on FM. The believed one way for scammers to convince peopleto share their personal information, is through FM tradings. For instance, P23-Sexplained her experiencing a potential scam situation: “The [FM scammers askfor] your login information for FB and ... they take over your identity. Becauseyou log into so many sites with your FB, they can ... drain your bank accounts,30credit cards, and everything.”Offline RisksSafety decisions were influenced by concerns about offline trading. Many partici-pants were concerned about their physical and emotional well-being. In particular,they were concerned about being killed, kidnapped, sexually abused, physicallyharassed, or subjected to emotional or psychological violence. We note that mostfemale participants expressed concerns about facing predatory or aggressive be-haviors while meeting with the other traders in person and offline. In addition,participants had concerns about losing money, damaging their reputation, inad-vertently contributing to crime, or being at financial risk. Due to such concerns,participants raised their caution. The participants (N=6), whose concern became areal incident such as scamming, took potential FM risks into consideration moreseriously when making decisions to trade with strangers.Particiants were concerned about their safety. We note that mainly female par-ticipants expressed concerns about facing predatory or aggressive behaviors. Ifthey sensed a potential for such behaviour from the other trading party, they con-sidered the transaction unworthy, and would rather forgo the trade. P15-S, forexample, said:“... anything like anger, which is also more common in men to comeout a little more aggressively... I rather not sell my $10 clothing item, if I am notsafe.”Participants also had trust and safety concerns about losing money and acci-dentally buying fake or stolen items. These concerns were about the consequencesof such transactions, such as the risks of losing money, damaging their reputa-tion, inadvertently contributing to crime, or being at financial risk. Participantsexpressed that despite building trust, they were still concerned about financial loss.For example, P12-B said: “... I had paid the money, but I did not have the car. So[I planned] to drive to a registry office to transfer the lease ... [The] five minutesuntil the drive to register [the car], was [the] most stressful time of my life... [I wasconcerned if] ... they [would have] never show[n] up...”314.1.2 SignalsIn this subsection, we will discuss the factors that could hinder or promote the de-velopment of TPS (check the factors with both yellow and green backgrounds inFig. 4.3 ). We found that participants paid attention to two types of signals: reas-suring signals that increase the sense of trust, privacy, and/or safety and alleviateconcerns about the possibility of facing risks while conducting a trade; and warn-ing signals reduce the sense of trust, privacy, and/or safety, and sometimes result ina decision to forgo a trade. We discuss such signals in the following subsections.We explain these signals together in the text and the framework in order to help thereaders understand the dual nature of these signals and compare and contrast them.Trader’s BehaviorTrust between traders was built through online communications. To this end, par-ticipants observed warning/reassuring signals from the quality and content of com-munications; the received suggestions for in-person trading related to time, place,and payment method; the requests for disclosure of information, and the behaviorthat is contrary to the culture of the community.Participants observed significant TPS-related warning/reassuring signals fromconversations on FB Messenger. In communications via Messenger, replying quickly,being polite, and asking relevant questions (e.g., technical questions about the item)were considered reassuring signals from a trader. On the other hand, when selling,participants perceived all the following types of interactions as warning signals:irrelevant questions (e.g., about one’s marital status); rudeness, use of flirting orpatronizing language (e.g., “baby”); persistent requests for the seller’s address;playing an emotional game by presenting a long sad story; having lots of gram-matical issues, which suggests that the buyer is not living in this country; or askingquestions that suggest that the buyer did not pay attention to the original listing.When buying, participants perceived the following types of interactions as warningsignals: replying to messages at an inappropriate time, suggesting that the personis not from that region; providing item information that does not match the photosin the listing; sending pushy responses to force the buyer to buy; responding tooslowly; or being uninterested in negotiating (e.g., where to meet).32A suggestion to “meet in public” on the one hand and a rejection of “meet inpublic” on the other influenced participants’ sense of safety and privacy. Meetingin public was perceived to protect participants’ privacy and safety, and showed,presumably, that there was no intention of criminal activity. On the other hand, therejection of meetings in public places acts as a warning signal. Interestingly, twoparticipants perceived a request to meet in public as a warning signal, because theysuspected a greater risk of being robbed as a seller, or purchasing a stolen item asa buyer. To illustrate, P04-B said: “... [as a buyer] I do not know if the goods arestolen. So [unless] I can [know] where they’re [sellers] living or they [items] arecoming from.”Disclosure of information was a reassuring signal for some and a warning forothers. Requests for a participant’s home address, email address, or phone num-ber were associated with safety and privacy risks. These participants were worriedabout the abuse of such personal information for harassment. For instance, par-ticipants were worried that their phone numbers could be abused with follow-upcontacts, or irrelevant or inappropriate messages in the long term after the trans-action had ended. However, some participants said that sharing phone numberscould improve their sense of trust because it showed the seriousness of the othertrader by trusting them with their phone numbers. Also, sharing numbers allowedparticipants to search the phone number online to see if it was a regional phonenumber and a genuine one. Participants protected their privacy by not sharing per-sonal addresses; instead, they met in public places as they felt safer that otherscould see them. Another benefit of meeting in public was considered the preven-tion of misjudgment of neighbors about the nature of trading. To avoid neighborsassuming that the participant is a sex worker, P21-S met and paid in public. Shesaid: “[In public] I am not alone with a stranger dealing with money. We all knowthe stories of sex work that go wrong ... that can be something that people expectwhen there’s cash being handed over if they are buying from you they are givingyou cash.”. In another example, P21-S explained her concerns about sharing theexact address when he is selling items: “I sell a lot of computers and sometimespeople come and pick them up from my home, sometimes I worry that the situationwhere I’m not home and someone ... break[s] into my house ... and maybe there’sa possibility of a theft occurring.”.33Payment method selection was made based on TPS-related considerations.Most participants preferred to pay with cash as it alleviated trust concerns by elim-inating the need to trust the other party. It was perceived as a way to protect par-ticipants’ privacy by not sharing their email addresses (as needed for online moneytransfers) and protect safety by preventing chargebacks, cancellations, or fake pay-ments. In contrast, transferring money online was preferred by others since it al-lowed them to maintain records and do transactions without carrying cash. Whilesome participants preferred to give or receive payments in advance, for others, itwas a safety warning sign. They viewed it as a financially unsafe move (i.e., payingbut not receiving the (correct) item). The use of PayPal for payments was consid-ered differently. As buyers, participants preferred PayPal due to the money-backguarantee [17]. However, when selling, participants considered PayPal paymentsunsafe, since buyers could claim their money back after they received the pur-chased item.Furthermore, being asked by the seller to meet at their home without any justi-fiable reason (e.g., the item being large or heavy) was also perceived as a warningsignal. P06-B, for example, said: “I was buying a chair, ... [there was a] man, andwe were meeting late at night and he [said] you have to come to pick it up insidemy condo; I can’t bring it out. That seemed a little suspicious to me and I wasn’tcomfortable with it, so I decided not to buy the chair.”Behavior contrary to the community’s culture increased trust concerns. Suchbehavior could be interpreted as malicious or ill intentions and acts as a warn-ing signal. To illustrate, P38-B said: “[city A] is undoubtedly probably the leastfriendly cities I’ve ever lived in, ... if someone wants me to get into their house, liketry to be super nice ... that’s not the culture ... that’s not the norm, so if someoneacts out of the norm, of course, that would be a bit suspicious.”FB Profile InformationThe completeness and authenticity of the traders’ profiles were perceived as signif-icant factors in TPS decision making. Having a FB profile that is authentic (e.g.,a real-sounding name, and FB posts that have been liked or commented on), not anewly created profile, a trustworthy profile photo (i.e, having a photo of a human),34and having similarities with the other trader were considered reassuring signals forTPS. In contrast, a lack of profile information (e.g., no friends or no Facebookposts), a newly created profile, mismatches between the buyer/seller and the of-fered items, and evidence of violence or aggressive behavior in a profile decreasethe sense of TPS.The age of the profile was considered very trustworthy information for deci-sion making. Because participants believed that such information could not bemanipulated by the profile owner. Newly-created profiles, on the other hand, wereperceived as especially alerting because participants were worried that the profilesmight have been created by scammers who were banned from FB and had to createnew profiles.Though a genuine-sounds profile photo increased the sense of trust, this trustwas hampered when the profile photo was missing or clearly had a wrong image.Profile photos that included a human face, and photos with family members (e.g.,children, or pets) were considered signals of the person being genuine. P26 said:“a younger guy with a picture of a spouse and kids I am like, ’well, it is a familyperson. So hopefully they would be okay.’ ... [he is] less likely to be violentor be a criminal.” Examples of types of images that our participants consideredsuspicious for profile photos include those without a human face, or images ofanimals, celebrities, and nature. The participants were worried that the trader wastrying to hide their identity and could be a scammer. However, participants, whowere unwilling to share their own photos explained that they were concerned abouttheir privacy towards the FB platform and its users. It is interesting to note thatthese participants’ decision making also depend on the consideration of photos ofother traders.Mismatch between the buyer/seller and the offered item was considered a warn-ing sign for trust and safety. A lack of correlation between the trader’s age or gen-der and the item reduced the sense of trust and made the request more of a safetyrisk. P24 noted: “let’s say it is a product for a man, but I see a 14-year-old girltrying to buy. I think that’s very suspicious ... it does not match right”.A sense of safety was significantly increased by observing similarities in theprofile of a trader. Having a similar age range and/or gender, having mutual friends,and being in the same university or group significantly increased the sense of trust35and safety. Similar to the previous findings in P2P shared identity to be a keypredictor of trust [80].A sense of safety was significantly decreased by evidence of violence or ag-gressive behavior in a profile. Profile photos containing weapons, aggressive ges-tures, or drugs, or any information in FB profiles suggesting sex trafficking, sex-ual violence, or alcohol consumption, and any radical or predatory written postsdeemed for a number of participants important warning signals that overrode per-ceived benefits of a trade (see Section 4.1.4).FM Profile InformationHaving a verified badge from the platform and several ratings were associated withincreased trust. Verified badge was considered as an important reassuring signalto build trust because it added another layer of support by the platform. Severalparticipants not considered ratings. The reason was they were unaware of this fea-ture, believed it was not useful for non-professional sellers, opinion of others abouttheir experience, does not come with an explanation to be helpful or considered itunreliable as it could be manipulated. Some other participants believed it was stilluseful to consider rating. Because they believed (1) not all ratings were manipu-lated, (2) it was treated with a grain of salt, (3) even if it is manipulated, it was theseller’s investment. For instance, P33 said: “Because at least they spend money tomanipulate .... this effort means they actually put effort and if I give them a badrating and other people see that, it’s going to measure their reputation and the in-vestment...they’re [not] gonna risk a future transaction for that kind of ratings andinvestment they already did.”An unusually high or low offer related to the trade of an item alerted partici-pants regarding the trust and safety of the trade. Even though a low price for anitem to be purchased, or an additional payment for an item to be sold, sounded ap-pealing to participants, these offers raised their sensitivity to other warning signals.As an example, P25-S explained her experience of being close to falling into ascamming scenario: “When it sound[ed] too good to be true, I Googled it, becausesomeone’s paying $400 for something that’s $200. ... He had said a few things likean alarm bell [went] off ... like one he said he wants to pay on PayPal ... I Googled36the username of the person. I was really shocked, because a lot of [other people]were falling for it [exactly the same person and suggestion].”Presentation of listings, types of items, and the number of listings from a sellergave different signals related to TPS factors. For some participants, the seller whohas a large number of FM listings was considered a reassuring signal. The partic-ipants observed that sellers with a larger number of listings appeared to be moreprofessional. This could be attributed to the absence of any negative feedback aboutthem, which suggests that if there were any issues, they would have been raised bynow. However, some participants viewed large listings, unusual, or uniform listingsof items for sale with suspicion. They would become concerned that items mightbe stolen. For instance, P21-B explained why she avoids buying from such sellers:“In [my city], there is a lot of thieves, so if you get somebody who consistentlysells electronics or bikes or things like that... you are going to [be contributing to]proceeds of crime.” Several participants noted that they deleted their listings afterthe sale due to privacy aspects. In regards to the listing’s photo, authentic photos ofthe items, not copied from the internet, and clear and informative photos of goodquality taken from various angles were reassuring signals that assisted participantsin making better judgments to prevent any financial loss or scams.FB SupportAlthough certain FM features provided support to users in TPS aspects, they alsopresent some challenges that are not entirely beneficial in this regard. Some FMfeatures were associated with the sense of TPS. The existence of blocking, re-porting, hiding from friends feature, and privacy setting mechanisms improved thesense of TPS. Participants commented that blocking gave them the feeling that ifanything were to go wrong, there would be a feature that they could use to stop allinteractions and access of other traders to them or their data. However, as discussedpreviously, this feature can be abused by traders with ill intentions. Furthermore,hiding from friends feature while is helpful to protect the privacy of participants bynot sharing their personal tradings with their friends, was not visible for all partic-ipants, or sometimes they forgot to use it as was not clearly presented to them. Inaddition, the existence of machine learning suggestions by FM made participants37worried about their loss of privacy via the platform. Finally, inadequate response inthe case of problems and unclear notifications and warnings reduced participants’trust in the platform.Because FB did not adequately support the removal of scammers, users wereleft with the impression that they could not trust the platform and were insecure.The participants raised the point that they could not trust FM because FB was per-ceived as unhelpful in banning scammers and preventing similar scams affectingother users. P05 said: “Maximum I can do is [to] report a person on FB ... max-imum will happen is just that person will get blocked or lose access to FB ... Iguess that’ is the maximum punishment [he] would get. But then he can open an-other profile.” Participants were concerned if scammers can reopen a new accounteasily [61] and continue the scam on users, which could harm society by breakingpeople’s trust in each other. Evidently, several participants stated that they movedfrom other P2P marketplaces to FM because there were more incidents of scam-ming on those platforms.Inadequate user support by FM reduced participants’ trust in the platform. Inthree problematic situations, participants found FM responses unclear and/or un-satisfactory. For instance, P16-B was temporarily suspended from FM: “I copiedthe link [of the listings] and pasted it ...sent them to some of my friends ... thenafterwards, some of my friends reached back out to me, and they said ... it[thelink] says that it’s not available or not displaying anything... that’s kind of weird.Because I have done this before, but this time I don’t know what was happening,they [FM] just temporarily banned my account.” He continued:“[I received a no-tification said that your act is] against the rules or against the guidelines.” He wasnot sure about the reason for the block, and his perception was that maybe he sentit too fast, or to too many friends.Participants expressed concern about the potential loss of privacy through theplatform’s machine learning suggestions. They conducted their own investigationinto these concerns and found evidence to support them, which further heightenedtheir worries about the platform. Foe example, P21-B stated: “ ... that’s concerning... if they [FB] have access to all my listings and things that I sell they know me ...sometimes on purpose ... [I] talk about dinosaur underwear. I notice suddenly myads on FB ... [is about] sell[ing] dinosaur underwear.”.384.1.3 Social NormsIn this subsection, we will discuss the factors that influence the priority of TPS.Social norms were among the important factors that reduced the priority of TPSin decision making. Social norms are “shared standards of acceptable behaviorby groups. Social norms can be informal understandings that govern the behaviorof members of society, as well as be codified into rules and laws [22].” Thesenorms include perceived trustworthiness, meet-up choices, and payment methods.Despite the fact that participants knew they might be risky, they are given a higherpriority to social norms than TPS.Perceived TrustworthinessCommon beliefs in societies form how participants evaluated the trustworthiness ofothers. Participants, as explained in section (Sec. 4.1.2), evaluated some elementsin the users’ profile photos (e.g., whether they have a family) to estimate whetherthe other person would be honest and trustworthy. These perceptions were basedon common beliefs about people’s personalities [156]. However, such judgmentscould be misleading. For instance, P29-B faced a scamming situation because shesaw family members in the seller’s profile and built her trust on that. Anotherexample was P28-S, who removed her profile photo to prevent prejudgment aboutAfrican Americans. She said: “... the first time [when I was selling], I did notreally want to have my picture up. Because I feel sometimes people think as anAfrican American person they stereotype me as somebody that will rob them orsteal from them. I feel somebody is less likely to buy something from me becausethey wouldn’t trust me.”Trading Unwritten RulesMeeting up in private places was perceived as a norm for participants who lived insmall cities. Participants who lived in a small community suggested that most ofthe people in that community knew each other in person. The buyers and sellers,therefore, did not follow the safety precautions that were frequently suggested byFM [19] or the police [15]. P18-B, who was living in a town with about 800 people,but used to live in a bigger city, compared her safety strategies adopted when living39in these two places and said: “[Here in this small town] I just go to the [traders]house, but certainly ... in the [in a bigger city], it was often you would meet outside... There are less than 800 people [in the community]. You are not going to [getmissing].”Another norm in a community is that safety may be compromised by someunwritten expectation related to payment methods. In spite of the fact that payingin advance and paying large amounts of cash is unwise and potentially dangerous,some participants in smaller communities or cities feel that they should follow thenorm in their community and always pay in cash, even for expensive items. Forinstance, P19-S reported that cash transactions were customary even when sellinghigh-value items such as a $700 truck during their residence in a rural area.4.1.4 Perceived BenefitsIn this subsection, we will discuss the factors that influence the priority of TPS.Sometimes, as a result of their exceeding interest in a transaction, participants tookrisky online actions and reduced the TPS priorities in decision making. For par-ticipants who had been scammed previously, caution and safety were of higherpriority in their decision making. However, for others, sometimes the perceivedbenefits of a transaction could reduce their TPS priorities. While previous studiesreported that consumers’ perceptions of benefits affect their intention to make anonline purchase [98], in this study, we found the factors that might influence thepriority of TPS, including convenience, personal interests and financial gain on FMtrading.Financial GainA determination to buy /sell an item could reduce the priority of TPS. A strongdesire to sell might come from trying to get rid of unnecessary items, making morespace in the house, moving to a new home, making money, completing a shoppingtask quickly, and performing altruistic work. A strong desire to purchase mightstem from trying to save money or not miss out on purchasing special items (P2Ponline shopping is a good place to find scarce items [61]). Buying unique items andbargain prices were two other perceived benefits that influenced decision making40by reducing the priority of TPS.ConvenienceTransportation of big items, as well as the type of residency (e.g., apartment, house,etc), were found to influence sellers’ TPS-related decision making regarding dis-closing personal information. When sellers of large and heavy items are not able tomeet in public, they have no option but to provide their exact addresses and permitstrangers to enter their residences. Both of these actions raised safety and privacyconcerns for participants who found themselves in this situation and said they hadno choice but to meet the buyer at their home. Participants sometimes disclosed in-complete address information as a means of addressing their privacy concerns. Forexample, P02 explained: “I was selling or giving away stuff from the house andI gave the exact address. Now, I am in a living-story building. I just give out theaddress of the building. Not my unit number.” Participants believed that apartmentbuildings could be safer and better for privacy than single-family houses.Lack of time or convenience of a payment method was also found to cause TPSfactors to be prioritized less. For instance, P06, who always checks the profile ofthe sellers as a strategy for TPS, said: “I remember when I was looking on FM fora new apartment. I needed to move out in a time-sensitive manner, so I was mes-saging everyone who had a listing that qualified for what I was looking for. In thatcircumstance, I do not remember looking through everyone’s profile to see whatthey look like and all that stuff that I described before.” Similarly, payment meth-ods also sometimes depend on convenience and time-saving for participants. Wefound cash payment could provide advantages such as eliminating delays, betterconvenience, not charging taxes, and not requiring mobile data.Personal InterestsA strong desire to purchase or sell an item reduces the priority of TPS. Some par-ticipants had a strong desire to purchase certain items, and they chose to ignore theidentified warning signals. Instead of focusing on the price of the items, partici-pants were more attracted to the items due to their qualities, brands, and aesthetics.For example, P03 said: “I really wanted a bike and then I saw this person ... she41had the photo of some famous Bollywood actress, so, I went to check ... she sellsa lot of stuff; it seems she is running a business. If somebody is running a sellingbusiness on FB, then I have reservations about that because I feel like I can nottrust their price.” In terms of why she then decided to buy it, she said: “I like thebike! ... I went with my partner. I did not go alone.” Similarly for selling theiritems.4.1.5 Platform DesignIn this subsection, we will discuss the factors that influence the priority of TPS.We found that the usability, cooperation support, coordination tools and populariyof the FM were critical factors for participants to decide whether or not to use aP2P marketplace platform. Although participants were aware of the drawbacks ofP2P transactions regarding TPS on FM, they perceived the platform’s interface,tools, and service as motivational factors in deciding to use it. This confirms priorresearch that has shown these factors were effective motivators for purchasing onS-commerce platforms [104]. Consumers are more inclined to use a website witha well-designed user interface and make online purchases as a result [63].Platform Usability and PopularityThe usability of the FM was found to increase participants’ desire to use it. A quicklisting process, rapid communication via messenger, and ease of use of featureswere among the elements that motivated participants to use the FM. Consequently,they used it more frequently than other similar platforms that had better TPS sup-port. Consistent with the findings of Evans et al.[61] which showed the limitedbarriers to joining Facebook groups, and encouraged users to use, we also foundthat this was a valid reason for using FM. Although the ease and speed of commu-nication on Facebook are not novel findings, as flexible communication tools havebeen discussed in previous research[61], our study highlights the trade-off betweenthe priority of trust and privacy concerns discussed in Section 4.1.1 related to theplatform.Despite some privacy and safety concerns, participants preferred using FMover other P2P marketplaces due to its effectiveness in reaching a wider audience42and selling items faster. Participants in our study reported having used Craigslist,VarageSale, or Nextdoor. They appreciated these platforms for their unique qual-ities, such as the ability to remain anonymous on Craigslist, better incident reportsupport on VarageSale, and the ability to select specific areas for buyers to viewlistings on Nextdoor. However, they noted that FM was more effective, given itspopularity and the larger number of active users and available items. For example,participant P24-S stated: ”I was moving in two days and ... I really needed to sellthe couch so I put it on the Facebook Marketplace ... and within a minute, around20 people contacted me...”. Although some participants expressed concerns aboutprivacy and safety issues on the platform, they still found FM to be the most effec-tive means of reaching a wider audience and selling their items faster and easier, asthere were no similar platforms with such extensive outreach.4.2 TPS-Related StrategiesAfter determining the TPS factors that participants associated with decision mak-ing, we investigated how these decisions formed users’ actions. The participantsused four types of strategies: trader selection and screening, information collec-tion and sharing, negotiation of in-person trading details, and in-person interac-tion. These strategies include using tools, watching conversations, selecting spe-cific groups for trading, avoiding transactions, accepting risks and doing the trans-action, sharing more information, gathering information about the item, reviewinginformation, gathering evidence, informing others about the meet-up, managingcontact information sharing, choosing specific payment methods, discussing meet-up aspects, meeting in specific spots, alerting the other trader, carrying safeguardtools, having a companion, finishing the trade before leaving, providing support,and acting asymmetrically as a buyer versus a seller. The theoretical framework ofthese strategies is presented in Figure 4.5.During our discussion in Section 2, we outlined the different steps involved inthe user journey on FM. In this part of the Results section, we analyze the strate-gies employed by the participants in our study and demonstrate how their actionsaligned with these steps. Figure 4.4 provides a visual representation of this align-ment, highlighting the different stages of the user journey and the corresponding43behaviors and actions observed in our participants.Figure 4.4: Alignment of Participant Strategies with the User Journey on FM:A Visual Representation4.2.1 Trader Selection and ScreeningHere, we discuss several strategies that participants used to protect their privacy,gather information about other traders, and select groups to trade with on onlineplatforms. Participants use various tools, such as the ”hiding from friends check-mark,” blocking, and reporting features, to protect their privacy and safety. Ratings,although not viewed as trustworthy by most participants, were considered usefulby some. Participants also observed warning and reassuring signals during con-versations with other traders to determine their trustworthiness and potential risksinvolved in trading. Finally, some participants opt to trade with buyers from theirown demographic groups to feel safer and trustworthy.Using ToolsSellers use the hiding from friends check-mark to protect their privacy. Participantsconsidered hiding from friends check-mark helpful as they used it to hide their list-ings from their friends. The reasons for using this feature were that the participants44Figure 4.5: Framework of TPS-Related Strategies on FM: Main StrategiesPresented with Gray Background and Subcategories in White.did not want to sell their items at a cheaper price, and that they did not want theirfriends to know about their personal lives and trading histories, for fear of possibleembarrassment or shame.Block feature and privacy settings helped to protect privacy and safety. Becausethese tools prevent access to and abuse of information, many participants usedthem. They said that as soon as they did not feel safe continuing conversationsor trading with others, they could block or report them. For instance, participantsused blocking to address their concerns in situations such as being worried aboutabuse of their information, preventing harassment, and protecting their emotionalsafety. Blocking is helpful because the other trader will not have access to their FBinformation and can not contact them.Participants used reporting but disagreed on whether it would help protect fu-ture users. Some participants, even those who believed FB would not respond totheir report, reported scam situations. Others reported on the assumption that FM45staff could help them in case of a problem. However, all but one said they did nothear from FM when they reported the scam issues. All of the participants whoreported a suspicious trader believed reporting might help future traders to avoida similar scenario, but that it was not very helpful for themselves. For example,P25 said “ Just because it helps maintain, like, a trustworthy marketplace commu-nity, I think a lot of people would just leave the platform if it turns out that there’sa lot of people who are faking their postings or they’re selling stuff .... I think alot of people will just leave the platform and try to find something that’s more se-cure.” Furthermore, they lacked knowledge regarding Facebook’s evaluation anddecision-making process, as well as its procedures for following up on reported orblocked situations.While ratings are used by some users to build trust on FM, many participantsin our study found this feature to be ineffective and untrustworthy. They did notview ratings as a dominant strategy to assess the trustworthiness of the other trader,as it could be manipulated, and the current format was not seen as a reliable sourceof information. Furthermore, participants felt that the ratings did not provide acomprehensive understanding of the other trader, such as their personality or re-liability. This lack of a personal connection created an environment of distrust,making it difficult for participants to gain reliable information from this feature toengage in the transaction. This finding is contradictory to some previous studies ins-commerce that showed rating is a significant feature for building trust e.g., [72]).However, while some participants were aware that ratings might be manip-ulated, they believed that they were nevertheless useful to consider. First, theybelieved not all ratings could be manipulated. For example, P38, a 28-year-oldparticipant, stated: “you can maybe manipulate 1,2,5 or 6 ratings, but if some-body let’s say has 80 ratings, it’s very hard [to fake] ... You couldn’t.”. Second,participants said that they considered the ratings with a grain of salt.Watching ConversationsIn our study, participants carefully evaluated both the warning and reassuring sig-nals (Sec. 4.1.2) exhibited by the other trader to assess their trustworthiness anddetermine the potential risks involved in completing the trade. In order to verify46the other trader’s identity and reliability, participants looked for warnings or reas-suring signs in their communications. These signals, which were observed duringinteractions, requests, and responses, were identified as the most influential fac-tors in decision-making. Based on their evaluation of these signals, participantsreported that they might opt-out of a trade to preserve trust, privacy, and safety.Thus, by considering these signals, participants were able to make more informeddecisions when trading on FM.For instance, many participants carefully observed their conversations. Theyconsidered such observation the initial step to gaining an idea about the other traderto build trust. During their conversation, if they saw any mentioned warning sign(Sec. 4.1.2), they would stop the conversation and avoid trading with that person.For example, P34 said:“having that interaction might have helped a little bit, notto say that someone who is potentially running like a scam couldn’t lie or talk well,but I think building that kind of connection or just chatting with a person definitelyhelps ... if they were short or something was off in the way that they typed or theway that they asked questions or proposed stuff caused red flags... ”.Selecting Specific Groups for TradingTrade with buyers from their own demography to feel safe. Participants who havepreviously experienced racism, predatory behavior, or scams tend to select peoplefrom their own demographic groups, such as age, gender, or ethnicity. Also, oneparticipant noted that better and more effective communication is another reasonto select buyers from their own country. As mentioned above, many participantsfound that trading within their own demographic group(s) provided a sense of trustand security. P15 said: “...young girls from the University that I feel most com-fortable with...”. When the researcher asked which age range made them uncom-fortable about selling, P15 said “ Definitely all older men, like at least 40 plus,probably in their 50s, what their images look like, but I would say, maybe 40 plusis where it started. Age-wise! .... Usually, for younger people I give it a little bitmore of a chance...”47Avoiding TransactionsFor expensive items, participants took more precautions when purchasing/selling.Participants explained that certain items, such as bicycles, electronics, or woodenfurniture, were risky to buy on FM because of the lack of warranty and/or returnpolicies, non-obvious defects (e.g., bedbugs for wooden items), the risk of losingmoney, or the physical risks of carrying large sums of money. So, some participantstook extra effort by inspecting the items more accurately, bringing a relative orfriend to assist them in evaluating the item and protecting their physical safety, ormeeting at the police station. Others preferred to not buy such items from FM,which is discussed in the last section.Accepting Risks and Doing the TransactionAs discussed in the previous section, our participants consider various factors whenengaging in P2P transactions on FM. Despite the potential risks involved in suchtransactions, they ultimately decide to accept these risks and proceed with the trans-action. This decision could be influenced by several factors, such as the perceivedtrustworthiness of the seller, the nature of the item being sold, and the convenienceand cost-effectiveness of the transaction. In any case, our participants demonstratea willingness to take calculated risks and engage in transactions that could poten-tially benefit both parties. This highlights the importance of building trust andestablishing clear communication in P2P transactions, as these factors can helpmitigate risks and improve the overall experience for both buyers and sellers.4.2.2 Information Collection and SharingHere, we discuss the various strategies used by participants to gather informationabout the item being sold on FM and the ways in which they share this informa-tion to build trust and credibility with potential buyers. Participants take stepssuch as reviewing photos, cross-checking the seller’s information with other onlinesources, and checking Facebook profiles to identify potential warning or reassur-ing signs. They also gather evidence to provide proof of purchase and inform theirrelatives of the meet-up to protect their safety during the transaction. The sectionhighlights the importance of providing clear and detailed information about the48item being sold and establishing trust and credibility with potential buyers throughtransparent communication and honesty.Sharing Extra InformationParticipants take actions to demonstrate their trustworthiness to potential buyers.Some of these actions include providing additional information about the item,agreeing to meet in a public place, or even bringing along a dog as a means of re-assurance.For instance, some participants who removed personal information fromtheir FB profiles added more detailed information about the item, in order to com-pensate for the lack of information about themselves. In another case, the par-ticipant brought her dog to give the impression that she was a reliable individual.She had heard that people were bringing their dogs to other P2P platforms, suchas Tinder, to indicate something about the character of the person. She believesthat would alter the buyer’s perception. She believes the trust between them at thatmoment is based on perceptions as they just spend a few moments together.Gathering Information About the ItemWhen considering a P2P transaction on FM, our participants took a number ofsteps to gather information about the item being sold. They typically started byreviewing the photos provided by the seller and looked for any warning or reas-suring signals related to the item (such as those discussed in the seller’s commerceprofile). For example, they scrutinized the quality of the photos to ensure that theywere clear and accurate representations of the item, or they cross-checked the priceof the item against similar items being sold elsewhere to ensure that it was reason-able. By taking these steps to gather information and evaluate the item being sold,our participants were able to make informed decisions about whether to proceedwith the transaction and to negotiate a fair price with the seller. This highlights theimportance of providing clear and detailed information about the item being sold,as well as establishing trust and credibility with potential buyers through transpar-ent communication and honesty.49Reviewing InformationChecking Facebook (FB) profile is the most common strategy for gathering in-formation. All but two participants checked either the seller’s and/or buyer’s FBprofiles, in order to identify potential warnings or reassuring signs (Sec 4.1.2).Participants indicated that checking profiles was the most distinctive and helpfulfeature of FM, as compared to other P2P marketplaces.The buyers cross-checked the seller’s information with other online sources toensure that the seller was authentic. Participants said when they were buying onFM, they preferred to cross-check for information about the seller in online sourcessuch as Google. Such information includes names (to find out if the person has abad reputation, phone numbers (to check for legitimacy), and locations (to confirmthe location and the reputation of that area). For example, P12 said:“If I havetheir name, I would Google it for sure to see if that person is, for example, anemployee of a very famous company or is there somewhere on the internet.” Someparticipants preferred to meet in neighborhoods in which they were comfortable.mention what P42 said.Check local FB groups dedicated to scam reports for warning signs. Partic-ipants who had access to or awareness about such FB groups used them to (1)raise awareness about local people reporting scams; (2) learn about various typesof scams in the area; (3) discuss how to prevent such scams. P10 checked such FBgroups when he had some concerns about a buyer:“If I have a situation where I’mnot sure about a person or their profile looks suspicious, I will check in there. ...the rules for the group is, you have to provide the screenshots. You can’t just blamesomebody without any kind [of evidence]...”Gathering EvidenceProvide documentation from the interactions. The participants used different tech-niques to record artifacts that provide a proof of their purchase, mainly becauseof concerns relating to buying stolen or fake items or being financially scammed.Later, if police were to ask for proof of purchase, or information about the seller,the participants would have a piece of evidence. They would also have evidence ifthey needed to demonstrate to a financial entity that they require a refund. These50techniques includes making screenshots of the seller’s profile information (includ-ing name and photo), just transferring money to have a record of the transactionand putting a note in the transaction that this is related to X-purchase from FM.For instance, P22 said: I usually take the screenshot of the product, the person’sprofile name, I’m taking a picture of the receipt with a confirmation .... Because Ihave proof that I paid for it, so if I need that proved, I’m able to show it to PayPalso that I can dispute the transaction.... that way would be safe, if something goeswrong.”Informing Others About the Meet-Upparticipants used a strategy to protect their safety by informing their relatives ofthe trader they were meeting and asking them to follow-up if they did not hearback from them after the meeting. Participants who used this strategy often feltsafer and more protected because they knew that someone else knew where theywere and who they were meeting. This helped to ensure that if something wentwrong during the transaction, their relatives would be able to take necessary action.Overall, this strategy helped participants to feel safer and enabled them to conducttheir transactions with peace of mind.Some participants needed to identify themselves in unfamiliar neighborhoodsin order to protect themselves. P09 said that, as an African American, she hadsafety concerns when trading on FM immediately following the murder of GeorgeFloyd [20], because some African Americans had been shot while in specific areas.She expressed concerns about being shot. She said: “ when I had to do somethingfor my baby, I had a T-shirt and I took a sign with me ... I had a sign “please don’tshoot me; I’m here for my FB market pick up.” .... it was on the neighborhood,was Daniels island, but there was a lot of shootings with African Americans at thetime, and a lot of protests. I didn’t want anything to happen to me.”4.2.3 Negotiation of In-Person Trading DetailsHere, we discuss how participants in the study used different payment methods andnegotiated meet-up aspects based on their trust, privacy, safety, and convenienceconcerns. The participants used payment methods like cash and online money51transfers and negotiated factors like the time and place of the meeting based ontheir practical considerations. Additionally, participants who valued their safetyand privacy opted for porch pick-up as a viable option to avoid meeting the othertrader in-person.Managing Contact Information SharingPrivacy was supported by not sharing personal information with the platform norwith other traders. Based on their Facebook-related privacy concerns, participantsas a buyer or a seller had very restricted profiles and did not put more informa-tion on their profiles, even when they knew that their profile might resemble thatof a scammer. In addition, some (N=15) participants have some level of privacyprotection by not sharing extra personal information with other traders, due to theaforementioned concerns that such information could be abused (Sec 4.1.1). Someexamples of personal information not shared for privacy reasons include phonenumbers, email addresses, home addresses, real names, posts, and profile photos.For example, P42 said:“I have shortened my first name [and] my last name. ... Ijust took the first three letters of my first name and my last name... because it’s soeasy to get hacked. My pages are hacked right now.”Choosing Specific Payment MethodsIn our study, participants used different payment methods based on their trust, pri-vacy, and safety concerns. Many participants paid with cash, which eliminatedthe need to trust the other party and protected their privacy by not sharing theiremail addresses required for online money transfers. Additionally, paying withcash prevented chargebacks, cancellations, or fake payments, which ensured thesafety of the transaction. However, some participants opted for online money trans-fers, which allowed them to maintain records and do transactions without carryingcash. Notably, few participants paid or received payments in advance, which wasconsidered a safety warning sign by others. Paying in advance was viewed as fi-nancially unsafe as there was a risk of not receiving the (correct) item. The useof PayPal as a payment method was also evaluated by participants. When buying,participants preferred PayPal due to the money-back guarantee offered by the plat-52form. Conversely, when selling, PayPal payments were viewed as unsafe, as buyerscould claim their money back after receiving the purchased item. In addition, so-cial norms also influenced the selection of payment methods, such as paying inadvance even when aware of the associated risks.Discussing Meet-Up AspectsWhen participants plan a meet-up, negotiations often take place about the time andplace of the meeting. Factors such as convenience, safety, privacy, and accessibilityare taken into consideration when deciding where and when to meet. For example,it may be more convenient for participants to meet at a busy time of the day toprotect safety. On the other hand, participants may choose not to meet at a latetime of the day due to safety concerns. Additionally, the location of the meet-upcan also affect the negotiations. Some participants may prefer to meet in publicplaces such as cafes, parking lots, or stores, while others may opt to meet at homedue to privacy and safety concerns. However, when the size of the item beingexchanged is large, meeting in public places may not be feasible, which can lead tofurther negotiations and decision-making. Ultimately, the negotiations around thetime and place of the meet-up depend on the participants’ preferences and practicalconsiderations.Avoid meeting the other trader in-person to protect safety and privacy. Buy-ers and sellers who value their safety and privacy often choose porch pick-up as aviable option. Participants consider it a good strategy to protect themselves frompotential aggressive behavior and avoid disclosing personal information. More-over, in light of health concerns, particularly during the pandemic, porch pick-uphas become a contact-less option, ensuring that the health of the participants isprotected. By opting for this method, participants can complete their transactionswithout the need to meet the other trader in-person. Overall, for some participants,porch pick-up has emerged as a convenient and safe way for participants to conducttheir transactions.534.2.4 In-Person InteractionHere, we discuss various strategies and precautions used by participants to increasetheir sense of safety and trust during in-person meetings. The strategies includemeeting at specific spots, carrying safeguard tools, having a companion, alarmingthe other trader, finishing the trade before leaving, and providing support. Theparticipants use these strategies to mitigate the potential risks of malicious behaviorand to develop a level of trust with the other trader. They show asymmetricalbehavior in sharing information when acting as a buyer or seller to increase trustand negotiate the price.Meeting in Specific SpotsMeet at the seller’s garage to buy/sell in order to protect safety and privacy. Twoparticipants noted that when they had large items to sell or buy, they would oftenmeet at the seller’s garage. From the seller’s point of view, the garage was notconsidered “inside” the house, so they did not allow strangers to enter their housein order to protect their safety and privacy. From the buyer’s perspective, the wassafer than the interior, since they could more easily jump out of the garage, if needbe.Alerting the Other TraderWe found that some participants employed strategies to alarm the other trader dur-ing in-person meetings. One such approach was to bring a dog along as a meansof protection. If anything went wrong during the transaction, such as violent oraggressive behavior or theft, the dog would bark loudly and alert others in the area.Additionally, some participants informed the other trader that they would be bring-ing a friend to the meeting. This was seen as helpful in warning the other trader thatthere would be two people present, making it less likely for any malicious intent tooccur during the transaction. Overall, these strategies were seen as effective waysto increase the sense of safety during in-person meetings.54Carrying Safeguard ToolsFemale participants of different ages and from different countries used strategiesto intimidate traders who may be suspicious. Participants stated that if they felt thebuyer might have bad intentions, they would take action to feel safer. The actionstaken by traders to mitigate potential risks during a trade include informing othersabout the trade in case of any issues, bringing a dog that can bark loudly to alertothers, and carrying self-defense tools. For instance, P24 said:“... had a littleweapon and my phone ... just in case I have to fight them off. I have a pocket knife,just in case they were trying to, like, rob me or something.” Two other participantsstated that they had their dogs stand in front of the door so that if anything wereto happen, the dogs would bark loudly. They believed that this would inform otherpeople around them and also provide the seller with a sense of safety.Having a CompanionIncreasing safety measures helped to compensate for a lack of trust. Some par-ticipants reported instances in which they were very much interested in buyingor selling an item, but the other trader’s profile showed warning signs, such as anewly-made profile or a lack of photos or information. In such cases, they wouldstill go through with the transaction, but they increased their safety measures. Oneexample of such measures is having the company of either a human or a dog. Forexample, a newly created account was a warning sign for P34: “... a really goodprice ... Even though the account was new, he was selling other stuff and every-thing else was in good shape and they didn’t look like phoney pictures ... then Ibrought a friend ... he [the seller] didn’t come inside ... he pulled up to the front ofthe driveway.”Finishing the Trade Before LeavingWe found that finishing the trade before leaving the meet-up space was anotherstrategy used by participants to manage TPS concerns. Participants reported thatthey would not leave the meet-up until they had received the transfer of funds tomake sure they got paid. However, we also found that the waiting time for receivingthe transfer varied depending on the level of trust built during previous interactions55and communication with the trader. Some participants expressed that they werewilling to wait for a longer time if they had not built a level of trust (there is a lackof trust), while others preferred to receive the transfer later and leave the meet-upwithout having the money. The level of trust between the two parties played animportant role in determining the waiting time for receiving the transfer.Providing SupportProposing short-term support was another strategy to increase buyers’ sense oftrust. Two participants as sellers provided after-sales support by assisting buyerswith the setup process to build trust and protect their own safety when they wereselling electronics. For example. P10, who was selling second-hand computersfrom a school, noted that: “for the computers I’ll say we do 60 days of warranty ifthere’s some sort of problem. Sometimes when you sell used computer hardware,there’s a chance that something could break. That’s part of the reason we do 60days ... if something does break sometimes people are angry. I worry that they maythrow eggs in my house or something.”Acting Asymmetrically as a Buyer Vs. a SellerAsymmetrical behaviour in sharing information act as a strategy to develop TPS. Afew participants indicated that they would prefer to buy items anonymously, due totheir concerns about privacy and the ability to negotiate the price. However, theynoted that they preferred to sell items via FM, due to its wide reach to potentialbuyers and ability to review buyers’ information to build trust. P17, for example,stated: “for buyer privacy,... I prefer that I don’t have to have a FB account orbe able to have all my information out there to somebody that’s random that I’mjust buying a product.... if I’m using Craigslist or any of the other marketplacesout there, I’m anonymous. I’m not a person that you can put a face to... [or]do a background check on, like I do to people.”. In contrast, another participantpreferred to buy items via FM, as it would be easier to establish trust and protecttheir safety, when knowing the sellers. Yet, they preferred to use other platformsto sell items, to protect their privacy and remain anonymous. Similarly, in terms ofpayment, some preferred a method such as PayPal as a buyer, but not as a seller.56Asymmetric behavior in sharing information can act as a strategy to developtrust and promote privacy and safety in online marketplaces. Some participants inour study indicated a preference for buying items anonymously and selling non-anonymously. This was due to concerns about privacy and their ability to negotiateprices. However, they noted that they preferred to sell items via FM due to its widereach to potential buyers and the ability to review buyers’ information to buildtrust. For example, P17 stated, “for buyer privacy,... I prefer that I don’t have tohave a FB account or be able to have all my information out there to somebodythat’s random that I’m just buying a product.... if I’m using Craigslist or any of theother marketplaces out there, I’m anonymous. I’m not a person that you can put aface to... [or] do a background check on, like I do to people.” In contrast, anotherparticipant preferred to buy items non-anonymously and selling anonymously. Hepreferred to buy via FM because it would be easier to establish trust and protect hissafety by knowing the sellers. However, they preferred to use other platforms to sellitems to protect their privacy and remain anonymous. Similarly, some participantspreferred using methods like PayPal as a buyer, but not as a seller.57Chapter 5DiscussionWe identified various factors that influence users’ TPS-related decision-makingwhile trading on FM. We created a framework that introduces and describes howthe identified factors influence users’ decision making. In addition, we developed aframework that illustrates participants’ strategies for how they managed their TPSaspects. These frameworks provide the research community with a holistic viewof TPS factors and strategies and the interplay between TPS aspects in FM trad-ing. They also provide a more nuanced perspective on users’ challenges, tensionsbetween factors, existing trade-offs in decision-making process, and discrepanciesin taken actions regarding trading on FM. By shedding light on users’ challengesand needs on FM, and the factors and strategies. This thesis identifies informedresearch and design directions for FM-like platforms.Our data suggest that trust, privacy, and safety are intertwined in the decision-making process. Users take different factors into account when they make de-cisions. If they believe that the benefits outweigh the risks, they are willing toaccept the risks and follow through with trading; otherwise, they will back off.Unsurprisingly, we found that the TPS properties of FM play important roles inour participants’ decisions in trading goods online. We found that trust, privacy,and safety factors influence, directly and indirectly, attention to other factors inusers’ decisions and behaviours. For instance, when participants built enough trusttoward other traders, they had fewer privacy and safety concerns about the othertraders (Sec. 4.1.2).58In this section, we further discuss the implications that one can draw from thefindings. The most intriguing themes that emerged in our findings are the points oftension between privacy protection and trust building, using and abusing FM fea-tures, and warning and reassuring signals. Further, we discuss challenges arisingfrom entangling a marketplace with a social network site and the complexity of thedecision-making process for FM users. Through our analysis, we found trade-offsthat arise from the interplay between factors that develop TPS and factors that in-fluence TPS in decision-making, as well as discrepancies regarding what actionsthey take. Throughout the discussion, we also offer design recommendations andidentify future research directions. We hope that our findings will aid researchers,platform designers, and policymakers in improving TPS-related user experience inFM-like marketplaces.5.1 Tension: Privacy vs. TrustTrust and privacy are highly entangled, but not always in obvious or linear ways.The level of trust that an individual has when making an online transaction is pos-itively correlated with their level of privacy [113]. Irwan et al. [86] found that thedegree of privacy is a crucial factor in determining the level of trust and subsequentbehavioral intention of E-commerce customers. The study findings highlight thesignificance of protecting and maintaining the privacy of customers to establishhigher levels of trust among them. Our finding showed that participants’ concernsabout sharing personal information with other traders and the FM resulted in shar-ing less information through the platform. At the same time, sharing this infor-mation helps in building trust. The tension between trust and privacy began here.Reducing personal information on their FB profiles helps FM users increase theirsense of privacy, but reduces the trust of other traders. In other words, despite thefact that three types of trust are required: trust in technology, in the platform, andin other traders [37, 70, 97], the lack of any of these types of trust influences theprivacy concerns,(Sec. 4.1.1) with the FB platform and privacy concerns relatedto sharing information with strangers in Sec. 4.1.2). Therefore, participants tookaction to protect privacy by removing more information from their accounts (e.g.,real name and picture). Hence, although these participants were genuine, other59traders would perceive them as less trustworthy (Sec. 4.1.2), because FM users’trust is partly based on the other traders’ profiles (Sec. 4.1.2). As a result, othertraders have a limited amount of information on which to build their trust.Ensuring users are aware of the privacy implications while providing traderswith enough information to build trust. Unsurprisingly, resolving these tensionsdoes not appear to be a straightforward process either. While there is a lack ofinformation on how to protect users’ privacy, one could argue that users couldbe assisted through other factors they usually use to build trust. In terms of pri-vacy concerns toward the platform, FM could make instructions for data prac-tices more clear and visible, such as who has access to users’ data, howmuch andhow long their data will be available for the other trader,to guide users in makingprivacy-related decisions. Additionally, the platform needs to provide informa-tion and be transparent about the strategies taken to protect users’ data from pri-vacy breaches similar to previous such incidents [38]. Maintaining and preservingprivacy-sensitive data is an essential function of the service provider [36], which isnot adequately supported by FM. In designing for privacy, one possible approachis to use concepts of information flow [88] and leakage [106] in conjunction withPrivacy Regulation theory [29].Improving those trust-development features that need less disclosure of per-sonal information might be another strategy. For instance, our results suggest thattraders also use pre-transaction communications, mainly through FB Messenger, toassess trust (Sec. 4.1.2). There is a need for future research to see how the platformcould be redesigned or what new feature could be added to assist in giving warningor reassuring signals to users. Two sets of theories can help in the design direction:knowledge-based trust (KBT)[51] and identification-based trust (IBT)[109]. Thefirst can be used to establish trust for information sharing. The second can be usedin distributed systems where all participants need to have their identities verifiedin order to secure the exchange of data. Being able to verify whether users are le-gitimate users may help users build trust toward each other. For instance, adding anudging system [24] may improve the evaluation of signals that users can get fromthe traders’ communications.605.2 Tension: Using vs. Abusing FM FeaturesSome FM features have the potential of being misused. Previous studies in the areaof P2P marketplaces and social network sites, found different types of abusing fea-tures for building trust, such as fake accounts [139], fake profiles and identitiesin social networks [101], fake profile in P2P marketplace [116], and the abuse ofreporting feature on FB [146]. We call these features misuse-prone. Although fea-tures, including blocking, reporting, rating, and profile information, are designedto assist users in building trust and protect their privacy and safety, such featurescould be misused with negative consequences. We found these misused resulted infalling into scam situations, facing emotional harm, reduction of trust in the plat-form, and/or a sense of frustration for being left alone with TPS-related problems(Sec. 4.1.1).As a case in point, profile information could be a double-sided sword. Our par-ticipants often reviewed FB and FM profile information (e.g., profile picture) to getan idea about the trustworthiness of the other traders and the risks of transactingwith them (Sec. 4.1.2). This behaviour is in line with previous studies suggest-ing that a human face can be considered one of the most salient sources of socialinformation [156]. At the same time, a profile photo could be a tool for gainingunwarranted trust. For instance, one of our participants was trapped in an oppor-tunistic situation and trusted the other trader because of reassuring signs appearingin their profile photo (Sec. 4.1.3).Another feature that can be manipulated is the rating system. Although nu-merous studies (e.g., [25, 31, 40, 96, 97, 132]) have shown the importance ofrating systems in building trust in E-commerce and S-commerce, we found thatthis feature, in its current format, was not much helpful in the context of FM forusers. As we discussed in the introduction section, FM differs from previous com-merce platforms. Therefore, we believe the following aspects of the feature couldbe redesigned to (1) provide the visibility of the feature to all users, includingnon-professional sellers; (2) enable users to create labels instead of choosing thepre-defined labels to rate traders; and (3) explain the validity of the rating, such ashow many ratings were given by real users. Further studies are required to evaluatewhether such redesign can improve users’ experiences. Also, future studies are61needed to see how the reviews can be helpful in FM-like platforms. Future studiescan use machine learning techniques to study how to improve the helpfulness ofreviews and ratings (e.g., a study by Singh et al. [141] for Amazon users).New methods of user assistance are necessary on platforms such as FM. Profileinformation helps users to assess how genuine an account is. However, there is noway to verify the authenticity of such information (e.g., name, real pictures of onetrader, etc.). Therefore, there is a possibility that scammers may use fake profileinformation to create a false sense of them being authentic person [134]. In thecontext of social networks and sharing fake news, Wang et al. [152] found that ver-ified accounts with a badge significantly weaken the impact of identity verification.There is a need for further studies examining the role of verified accounts, the for-mat of verification, and the affordances of verification when using a marketplacewithin a social network. The verification is critical in the FM platform, where usersmay be reluctant to provide more personal information to the platform itself due totheir concerns. We found that participants were reluctant to provide more personalinformation to the platform itself due to their concerns discussed (See Sec. 4.1.1).Future studies should investigate whether users would be willing to provide morepersonal information to FM in exchange for a verified account badge. This wouldprovide valuable insights into the level of trust and confidence users have in theplatform and how it can be improved.Implementing TPS strategies may be the avenue for future work. Consideringthe popularity of the FM, with one billion visitors per month, finding a way foridentity verification may be necessary. In addition, as discussed in Sec. 4.1.2, poorFM support on conflicts in trading transactions is unclear and questionable. Partici-pants were not aware of how FM investigates reported problems. This is in contrastwith other P2P platforms. For instance, Lyft reviews any driver whose rating fallsbelow a specific level [60] and deactivates them if their rating is less than 4.6 [137].Similarly, every reservation made on Airbnb is assigned a “trust score,” and thosewith a trust score below a specific level are flagged for further inquiry [123]. Basedon Nielsen huristics [124], we believe the visibility of system status in this respectis not clear to FM users. Therefore, we suggest the system provide feedback withexplanations to users regarding their previous actions (e.g., feedback about users’complaint reports of another user) within a reasonable period of time [89]. An-62other strategy is to add new features that can help users evaluate the trust levelsof a trader without increasing privacy risks. For instance, the age of an FB profilehelped FM users to decide if it could be that of a scammer (Sec. 4.1.2). Profile ageis very trustworthy as it cannot be manipulated by traders. So, to increase the senseof trust platform can provide such information to users.5.3 Tension: Warning vs. Reassuring SignalsSome signals play dual roles in the TPS-related decision-making process. We dis-covered that some of the factors mentioned as warnings and reassuring signals(Sec. 4.1.2) are interpreted differently by various participants. We call these sig-nals two-sided signals. Two-sided signals on FM include sharing phone numbers,requests to meet in public places, larger numbers of listings, and payment methods(Sec. 4.1.2). We discovered these two-sided signals might cause tension betweentraders, which resulted in either (1) one party being suspicious of the other’s trust-worthiness, (2) assessing the chances of safety risks as high, or (3) refusing to tradewith the other party (see Section 4.1.2). In addition to that, the findings of this studydemonstrate that FM users are heterogeneous in terms of TPS factors and strategiesthey take. This heterogeneity is important to acknowledge and consider when de-signing the platform, as certain design decisions may be made without consideringthe needs of certain user groups.To further enhance our understanding of user heterogeneity concerning TPS,there is a need for future studies to conduct a more in-depth investigation into thissubject matter. Although we observed differences between user factors and strate-gies, the classification of users was out of the scope of our work. Previous stud-ies in E-commerce and S-commerce have demonstrated and identified differencesamong users of these platforms with regard to gender [142] and role (buyers vs sell-ers) [154], and decision-making processes [85]. Despite the growing importance ofS-commerce platforms, there is still a lack of research on the understanding of thediversity among such platform users related to TPS aspects, in particular on FM-like platforms. Understanding the differences in management can provide valuableinsights that can inform product development decisions. It can also help ensurethat products meet the needs of diverse user groups and facilitate inclusive design63decisions. In addition, it can assist in the creation of user personas, which act ascommunication tools and conduits for user information [67]. These personas canhelp designers make informed decisions based on the varied needs of users (e.g.,[23, 147]).5.4 Challenge: Information Sharing Aspects ofEntangling FM with FBThe availability of data and features in the design of social network-based market-places needs to be reconsidered in order to better protect the privacy and safety ofusers. Our participants expressed concerns related to being held liable for a longtime after a trade (Sec. 4.1.1) regarding any problem with the item that they sold. Itseems that, in this case, FM violates the security principle of Least Privilege (i.e.,“a person should be given only those privileges needed for them to complete theirtask” [5]). There could be various ways to rectify this issue.The availability of transaction information for an extended period of time canpose a challenge for traders. It is important to conduct further research on howlong traders should have access to each other’s information to ensure that necessaryutilities, such as providing post-trading assistance, are protected and users’ privacyis maintained. Moreover, it is crucial to reassess the availability of social networkfeatures to FM users to effectively address challenges. It may also be helpful ifsome social network features are restricted in FM. A feature such as a friend requestis designed for social networks, and one should question why it is accessible inthe marketplace. Users should have the choice to remove this option from theirFM profile. Developers of social network-based platforms need to reconsider theavailability of different features for different applications.While the payment method is one of the most critical and challenging partsfor users to decide in trading, a lack of trust in the social network platform mayprevent FM from moderating payments. One example of the challenges that arisefrom placing a marketplace on a social media platform like Facebook is the reluc-tance of participants to share more diverse sensitive information with the platform.Participants considered agreeing on a payment method as a critical step in trading(Sec. 4.1.2). They expressed TPS concerns regarding the risks of financial loss,64information loss, and physical harm (Sec. 4.1.1). Thus, they adopted a variety ofstrategies that might sometimes be conflicting. If the other trader perceives thesepayment options as suspicious or, even more, refuses to use them, the transactionmight stall or even be canceled. A trusted third party (TTP) may help in such cir-cumstances because it can help both sides of the trade to establish trust toward eachother through the third party. In light of the trust concerns participants had regard-ing the sharing of information with the platform (Sec. 4.1.1), however, whether thepayment system through the FM and its moderation could present TPS challengesrequires future research.Promoting some features’ visibility could assist users in addressing the lackof information for building trust. In social psychology, it is well established thatpeople are more likely to favor members of their own group than members of othergroups [120]. Since the most common in-group communication signals and sym-bols are absent during electronically mediated negotiations, individuals are search-ing for clues in order to gain insight into the opponent’s intentions and goals [120].We found one reassuring signal that influences strongly in deciding whether todo the trading was the observation of having commonality with the other trader(Sec. 4.1.2). Platforms could make these commonalities more obvious and easy toaccess to users. In addition, users could be given a choice to outline the buyersthat they perceive could most benefit from the items. For instance, if a seller isselling a book for university students, she can be given the option to identify thatthe university students are the target buyer.5.5 Challenge: Complexity of the Decision-MakingProcessThe study’s findings suggest that FM users need to take into account several fac-tors when engaging in transactions. These factors include technological, practical,social, and personal preferences. Due to time constraints, users tend to favor plat-forms that offer increased usability. However, each transaction incurs hidden costs,such as the user’s assessment and associated risks. In addition, the decision-makingprocess involves evaluating various factors throughout both online and offline in-teractions. Moreover, in addition to developing trust in the other trader regarding65privacy and safety, users must assess the item’s condition, price, and transfer meth-ods of the item. Finally, they need to consider payment method, and transactionsafety before committing to a sale. All of these aspects make the decision-makingprocess complex.Existing theories of decision making from psychology and economics can pro-vide insight into how users make decisions. Scholars can consider incorporatingexisting theories of decision making, such as those from psychology and eco-nomics [30, 55], to better understand users’ decision-making processes. For ex-ample, in psychology, theories such as Prospect Theory [108]1 and the CognitiveDissonance Theory [79] 2 can help researchers understand why users make cer-tain decisions. From economics, theories such as the Rational Choice Theory [77]and the Bounded Rationality Theory [92] can provide insight into how users weighcosts and benefits when making decisions. Additionally, behavioral economicstheories such as Nudge Theory [41] can provide insight into how users can be in-fluenced to make certain decisions. By incorporating these theories into their work,researchers can gain a better understanding of users’ decision-making processes.A potential solution to assist users in this complex decision-making process isto provide more comprehensive information. This can be achieved by conductingstudies in information design and enhancing the visual aspects of the provided in-formation. When making decisions on FM, users must rely on both the informationprovided by the other trader and the platform. In light of this complex situation,designers should take steps to provide users with more robust and reliable informa-tion. This can be achieved by conducting processes to identify the different usergroups and their goals, defining information needs, defining information relation-ships, determining the sources of each piece of information, and creating a visualmodel to effectively present this information [28]. By doing this, designers canwork towards providing users with the necessary information to make informeddecisions when trading on FM. Future research is needed for each of these consid-1Prospect theory operates on the assumption that losses and gains are not equally valued byindividuals. Hence, when making decisions, people tend to prioritize perceived gains over perceivedlosses [43].2According to the Cognitive Dissonance Theory (CDT), individuals experience an unpleasantstate called dissonance when they have two or more conflicting cognitions. They must resolve thisstate by modifying their cognitions. [79].66erations.One possible approach in this context would be the service design approach asan alternative strategy for conducting research related to design for such tradingservices. To effectively design for complexity and trade-offs, we first need to seethese FM-like platforms as services with a holistic service design approach. Thisapproach emphasizes the need to design many elements simultaneously rather thanrelying on a single computational system to solve complex problems [64]. Whenwe want to design services, our approach needs to be aligned with it. Services aredifferent from products and require a different approach beyond User-Centered De-sign (UCD) and User Experience (UX) practices. Service design takes into accountmultiple stakeholders, considers the value in exchange for each party involved, andincorporates economic models in the design process [64]. This means that servicedesign involves not only thinking about the value for the company, but also thevalue for the individual stakeholder, and even the economic, transactional, and pol-icy aspects beyond the computer [64]. Service design is better suited to complexproblems than UX design because it considers all aspects of the user experience,including their interactions with the service, the environment, the people involved,and the technology. In this way, service design incorporates the user’s needs, thebusiness’s objectives, and the context in which the service is delivered. By pro-viding a more comprehensive understanding of the user experience, service designenables organizations to identify opportunities for improvement and develop inno-vative solutions.5.6 Discrepancy: TPS Strategies of Users vs. Police/FMDiscrepancies between police recommendations and users’ behaviors require a re-vision of safety guidelines. The findings of this study suggest that there is a needfor further research to bridge the gap between the police recommendations andusers’ behaviors. Despite the helpful suggestions provided by police and FM forensuring privacy and safety on the platform, users’ actions often do not align withthese recommendations. This discrepancy highlights the need for a more nuancedapproach that takes into account the reasons why users do not follow these guide-lines. Policymakers and platform administrators should consider the practicality67and feasibility of their recommendations, and assess whether they need to be re-vised to better reflect users’ needs. We presented the various strategies used byparticipants, as well as the recommendations suggested by FM and the police, inTable 5.1.New: FM suggest use Paypal as said: “Don’t transfer money directly into aseller’s bank account. Instead, offer to use a secure person-to-person payment site,such as PayPal.” [4], but users avoid it!Users’ limitations challenge the practicality of police recommendations. Oneimportant factor that explains why users do not always follow police recommen-dations is the practicality of these suggestions. For instance, users often prefer tomeet in private when trading big items, contrary to the police advice to meet inpublic spaces. This finding raises an important question about the relevance andpracticality of existing recommendations. Policymakers and platform administra-tors should consider the reasons why users do not follow their suggestions andreevaluate the recommendations to better reflect users’ needs while ensuring theirsafety.Participants’ own strategies for privacy and safety suggest the need for a moreuser-centered approach to safety guidelines. The study reveals that participantsused their own strategies to protect their privacy and safety, which were not sug-gested by the police or FM. This finding highlights the importance of understand-ing users’ perspectives and experiences when developing recommendations. Poli-cymakers and platform administrators should consider these alternative strategiesand assess their effectiveness in ensuring users’ privacy and safety. Overall, thisstudy highlights the need for more research to develop recommendations that arepractical, feasible, and effective in protecting users’ privacy and safety on tradingplatforms like FM.5.7 Trade-Off: Developing vs. Influencing FactorsFM users must consider trade-offs when making decisions. In this study, we foundseveral trade-off situations for users. These include (1) privacy vs. trust, (2) privacyvs. convenience, (3) safety vs. interest in trading, (4) social norms vs. safety, (5)safety vs. financial gain, and (6) privacy vs platform design. We found that the68trade-off between factors that lead to “the development of TPS (either hinder orpromote)” and factors that “influence the priority of TPS” reduce the priority ofTPS in decision making. Therefore, users’ privacy and safety might be at risk.Compromising privacy and safety is one consequence of such trade-offs. Previ-ous research in E-commerce has shown that consumers place a high value on bothprivacy and security [34]. However, factors such as ‘Pleasure’ features (e.g., con-venience and ease of use) were more important to users than privacy and securityfeatures [34]. Similarly, when the perceived benefits of the transaction outweighedthe TPS risks, people still engaged in trading [98]. Our findings also confirm theseprevious results, and we illustrate trade-offs exist in the FM trading. In some casesin which users faced a scamming situation, these compromises played a role, suchas in a trade-off between convenience and privacy protection (Sec. 4.1.4).One example of such trade-offs is the ease of use vs. privacy and safety. Us-ability features can influence purchase decision making, but can reduce the priorityof TPS. According to the literature, several usability features significantly affectdecision making at various stages of the purchase process. For instance, Liu etal. [114] have found that information quality, visual appeal, and ease of use havedirect effects on consumers’ emotions in cases of triggering online impulse pur-chases. The purchase decision-making process can be influenced by the quality ofthe design of a website with regard to information quality [150], ease of use [155],navigation [74], and accessibility [103]. Among the design features identified, easeof use played a significant role in decision making [84]. Social commerce users areable to achieve higher levels of performance with ease-of-use features. In essence,they facilitate the interaction between consumers and social commerce, facilitatethe use of information and/or services, and encourage consumer engagement [84].However, we found that they reduce the priority of TPS.There is a need for future work to examine the priority of these factors andthe development of a system that will help users visualize the trade-offs. Furtherstudy of the priority of these factors is essential to helping users. We found thatsome factors are outright deal-breakers for some participants, while others are not.Although investigating the priority of factors was out of the scope of our study,we believe it is crucial for future research to examine the priority of factors withgreater precision (as an inspiring example, in Airbnb, the host’s profile photo ap-69pears to have a greater influence than their reputation [59]). The results may informdesigners and developers of what modifications are most needed. Furthermore, theplatform can help users better understand the trade-off between factors and giveusers more control over their data by enabling them to decide whether to make thetrade-off. For instance, users could be made clear about the utilities of disclosingcertain types of information to other users, such as allowing other users to buildtrust toward them and make trading with them. Then, they could also be informedof the possible privacy risks they may have to bear by disclosing the information.As people value privacy and benefits differently [153], users could be given controlover whether they want to make the trade-off.To help users make better decisions regarding TPS, enhancing their understand-ing of security and privacy concepts and using strategies like gamification can beeffective. One solution for helping users in these trades-off decision making is toimprove their mental models. Among the principal goals of the usable privacy andsecurity research community is improving users’ mental models related to securityand privacy [133]. The research community needs to investigate new strategies forimproving the mental models of users regarding the signals we found (Sec. 4.1.2).Helping users to illustrate the risks could help to improve the mental model. orgamification3 [73] are among the possible options to make more informed TPS-related decisions.Future studies can also explore how we can assist users in optimal decisionmaking in trade-offs. Future studies can also explore how both privacy and trustcan be better supported without sacrificing either, and how users can consider con-venience without sacrificing safety and privacy. Understanding these trade-offs canhelp inform designers in building a product that meets user needs and expectationsand in creating optimal services.3“Gamification refers to technologies that attempt to promote intrinsic motivations toward variousactivities [73].”70ParticipantsStrategiesFMTipsPolicerecommendedScreening and Selecting the Traders —- —-use the hiding from friends check-markuse blocking D [4]use the privacy settingreview rating D [4]look for signs in communications D [4]trade with buyers from their own demographyselect sellers based on the age, gender and itemCollecting and Sharing Information —- —-check FB profile D [4] D [3]check local FB groups dedicated to scam reportscross-checked sellers information D [4] D [3]review the photoscheck the quality of the photoscross check the pricenot review ratinguse reporting D [4]Negotiating in-person trading details —- —-not share personal info with the other traders D [4] D [16]using an alternative email or phone numbernot provide their detailed address D [4] D [54]not accept advance payment D [4] D [3]accept advance payment D [4] D [3]not provide an email address for payment via e-transferavoid places considered not safeavoid using PayPalInteracting In-Person —- —-meet in public D [4] D [16]not meet at late time of the day D [4] D [16]meet at the police station D [16]meet outside the homemeet at the seller’s garagemeet at the busy place and busy timetake more precaution for trading expensive items D [4] D [54]avoid meeting the other trader in-personbring someone D [16]inform relatives of the trade & ask for their follow-up D [4] D [16]inform trader that will bring a frienddocument the interactions D [4] D [16]wait for receiving transfer depends on the level of trustinform the sellers’ neighbor about the FM tradingnot leaving the meet up until receiving the transferidentify themselves around a non-familiar neighborhoodintimidate the other trader using dogcarry safeguard tools such as a pocket knifeselect the places that they are familiar for meet upTable 5.1: Table of Strategies: This Table Illustrates Strategies Used by Par-ticipants, Strategies Recommended by FM, and Strategies Recommendedby the Police.71Chapter 6ConclusionIn conclusion, this thesis has explored the trust, privacy, and safety aspects of trad-ing on Facebook Marketplace (FM) and has investigated the diverse perspectivesand experiences of the platform’s users. Through a human-centered approach, aqualitative study was conducted, which included semi-structured interviews with42 participants aged between 19-75. The research findings reveal that FM raisesmany new trust challenges, privacy problems, and safety risks. The study devel-oped two distinct frameworks that describe the TPS-related factors and strategiesbased on participants’ experiences.The results highlight the importance of pre-existing concerns, signals, socialnorms, perceived benefits, and platform design specifics in shaping participants’decision-making processes around TPS when using FM. Moreover, the study iden-tifies four types of strategies employed by users, including trader selection andscreening, information collection and sharing, negotiation of in-person trading de-tails, and in-person interaction.The findings of this thesis contribute to the current understanding of TPS-related management aspects among FM users and offer insights for improving thedesign and functionality of P2P marketplaces. Researchers and platform design-ers can use these findings to identify potential areas of improvement for existingplatforms, to improve the platforms, find the other aspects of users’ challengessuggested in this study, and ensure better user assistance in TPS management onFM-like platforms. Finally, the study highlights the importance of continuous re-72search in this area to keep pace with the evolving nature of P2P marketplaces andthe related TPS challenges they pose.73Bibliography[1] Peer-to-peer (p2p) economy. 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In addition, wheneverparticipants noted anything about trust, privacy, and safety we asked the follow-up questions which are at the end ofthis document.FM experiences1. Why did you start to use FM?2. How often do you use FB? For what reasons?3. When?4. Can you please describe your most pleasant experience with buying or selling on FM?5. Can you please describe your most unpleasant experience with buying or selling on FM?6. Have you ever refused to sell to someone on FM? If so, why?FM and comparison with other platforms7. In the qualification questionnaire, you indicated that you used …., “e.g., I use Craigslist, Kijiji, etcWhat do you use Craigslist for? What do you use it for? (advantages and disadvantages)”Payment8. How do you pay or receive the fee? Why?Meet up spot9. Where do you see people buying and selling? Why there and not another spot? Why?Items10. You mentioned you bought different items from FM. How your experience was different based on thetype of item … vs …11. What type of items do you buy and what not? Why?Review information12. As a buyer, what information do you look for in an ad? Why?13. Have you ever looked at the profile of the buyer or seller? Why?14. What information are you sharing with others in your profile? Why?15. Do you use your real image? Why? What about your name? What information do you share withothers in public? (list of friends, profile images, posts, …)16. Have you ever changed any of this information or adjusted privacy settings for FM? Why?FM features17. What features do you like the most about FM? Why?18. What features do you dislike the most about FM? Why? (ask if they use it and ask why if they do notlike it, they use it?)Blocking:19. Do you know this feature allows you to block others? Have you ever used it?20. Does it matter if this feature exists? how and why?9021. What would be the consequence of using it? For both sides?Reporting:22. Do you know this feature allows you to report others? Have you ever used it?23. Does it matter if this feature exists? how and why?24. What would be the consequence of using it? For both sides?25. Do you understand when you should use it?26. What type of result do you expect to have by reporting?Rating system:27. Do you have ratings?28. Have you ever used it?29. How does it work?30. Have you ever rated sellers? Why?31. What elements are in the rating? What should it be instead?32. Do you trust ratings on FM? Why?33. If used on different platforms and compare?34. When you sell something what do you do? Do you indicate who bought the item? Why?35. Do you remove the listing? Why?36. How about your listings? Do you delete them? Do you keep it? Why?Hiding feature37. Have you ever used it? Why?Messaging38. What do you do with your messages after the trade? Why?Follow-up questions about TPS in any spot of the interview:(When participants brout-up the discussion about the TPS factors, we asked questions similar to the belowones)● Why is it a trust/privacy/safety issue?● What do you mean by trust/privacy/safety issue here?● Can you please explain more about the reasons why this is a trust/privacy/safety issue?● Who does this relate to your trust/privacy/safety?● How do you protect your trust/privacy/safety in such situations?91Screening Questionnaire921A study of the Facebook Marketplace user experienceThe main objectives of this research are to understand how Facebook Marketplace users use this platform and what features of it facilitate or make it challenging to trade with strangers.This short survey acts as a qualification questionnaire for a future interview study to understand user experiences in using Facebook Marketplace for sell and buy goods. Your responses to the questions in this survey will only be accessed by researchers associated with the study and will not be shared with any other entity. Your responses will be discarded once the interview participants are selected. Interview participants will be selected from the people who complete this survey. However, completing this survey does not guarantee you will be selected as an interview participant. No compensation will be given for taking this survey.If selected to participate, your involvement would entail a 1 hour interview via Zoom .If you have any questions or would like further information, you may contact [Removed for the anonymity of the submission]If you have any concerns or complaints about your rights as a research participant and/or your experiences while participating in this study, contact the Research Participant Complaint Line in the [Removed for the anonymity of the submission]Ethics ID number: [Removed for the anonymity of the submission]Q1. By checking Yes below, you agree that you are 19 or older and consent to us collecting some basic information about you (such as your age, gender, ...).Q2. What online marketplaces have you ever used for buying and selling secondhand products? (select all that apply)YesNoFacebook MarketplaceCraigslistFacebook GroupsWhatsApp GroupsvaragesaleKijiji932Q3. How often do you use Facebook Marketplace?Q4. When last time did you use Facebook Marketplace?Q5. Have you had a pleasant experience in selling or buying from Facebook Marketplace?Q6. Have you had an upleasant experience in selling or buying from Facebook Marketplace?Q7. I am using Facebook Marketplace for ....Q8. What items have you ever bought or sold in the Facebook Marketplace? (select all that apply)NeverOnce or twice a yearOnce or twice a monthOnce or twice a weekMany times a weekEvery dayOther YesNoYesNoBuying used products.Selling used products.Both (buying and selling products.)None of the aboveClothing & accessories.InstagramEtsyOther 943Q9. How old are you?(Please just number)Q10. How would you describe your sex?Q11. What is your ethnicity?Q12. In which country did you grow up?Q13. Which country are you living in? ElectronicsHome goods and kitchen stuffHome improvement suppliesMusical instrumentsEntertainment and hobbiesGarden and outdoorSporting goodsToys and gamesPet suppliesOffice suppliesVehiclesProperty for rentFree stuffFemaleMaleIntersexNot listedPrefer not to answer954Q14. Which city, town, village, or township are you living in?Q15. How long have you been in your current country?Q16. What is your level of education?Less than a year1-2 years2-5 years5-10 yearsMore than 10 yearsHigh schoolCommunity CollegeBachelor degreeMaster's degree or DoctorateOthers Q17. What is your current occupation?Q18. What is your annual income? (Please consider selecting in the range of Canadian Dollars (CAD))Please provide researchers with your email address:1 to communicate with you (if you are selected for an interview)$0$1 to $9 999$10 000 to $24 999$25 000 to 49 999$50 000 to 74 999$75 000 to 99 999$100 000 to 149 999$150 000 and greaterPrefer not to answer9651- to communicate with you (if you are selected for an interview)2- to compensate you for your time. Interviewed participants will receive their choice of either a $20 CAD Amazondigital gift card or a $20 CAD Interac e-transfer (US participants will receive an Amazon gift card equal to $20 CAD).← →97
Thesis/Dissertation
eng
Electrical and Computer Engineering
Vancouver : University of British Columbia Library
Attribution-NonCommercial-NoDerivatives 4.0 International
Graduate
Beznosov, Konstantin
Towards understanding trust, privacy, and safety management among Facebook Marketplace users
Text