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Main Mall Safety : An Evaluation of the Traffic Warning Sign Colors Ng, Joanna Conde; Ochoa, Hernan; Tse, Jocelyn; Leopando, Nicolandro 2016-04-22

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 UBC Social Ecological Economic Development Studies (SEEDS) Student ReportHernan Ochoa, Joanna Conde Ng, Jocelyn Tse, Nicolandro LeopandoMain Mall Safety: An Evaluation of the Traffic Warning Sign ColorsPSYC 321April 22, 201614532101University of British Columbia Disclaimer: “UBC SEEDS Program provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or a SEEDS team representative about the current status of the subject matter of a project/report”.Running head: Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors             Main Mall Safety:  An Evaluation of the Traffic Warning Sign Colors  SEEDERS  Joanna Conde Ng, Hernan Ochoa,  Jocelyn Tse, Nicolandro Leopando  The University of British Columbia  Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    2 Abstract   The purpose of this study was to evaluate the effectiveness of current bicycle traffic signs (BTS) implemented to encourage safe behavior between different modal-users on Main Mall at The University of British Columbia. The study sought to examine how different colors on traffic warning signs influence people’s interpretation of speed. It was hypothesized that colors with socially constructed meanings of precaution and attention to detail such as yellow and red respectively will yield more accurate interpretations of speed in regards to traffic warning signs. A structured survey comprising a fictitious scenario with color manipulated traffic warning signs measured interpretation of speed at which a fictitious character will ride his/her bicycle after encountering the sign. A numerical trend emerged demonstrating red, relative to green, complied lower perceptions of speed than the control, though not statistically significant. The results infer recommendations to UBC regarding how to elicit more precaution on Main Mall through established operations.    Keywords: Perception of speed, bicycle traffic sign (BTS),           Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    3 Introduction   To investigate what types of interventions would encourage safe behavior between different modal-users (e.g., pedestrian, cyclists, skateboarders) on Main Mall we began by examining what measures are currently being taken at the University of British Columbia (UBC) and consequently explored the effectiveness of such interventions.   Main Mall is the pedestrian core of UBC Vancouver campus. Stretching from the Institute for Computing, Information, and Cognitive Systems/Computer Science (ICICS/CS) to the Flag Pole Plaza, Main Mall is classified as a pedestrian priority route (Campus + Community Planning, n.d., p. 1). In lines with UBC’s public realm plan and its goal to create a vibrant and sustainable community UBC continues to advocate for alternative modes of transport. Through a range of programs UBC has managed to discourage the use of single occupancy vehicles, and instead has promoted the use of alternative modes of transport ranging from public transit, carpooling/sharing, cycling on campus, shuttles, Safewalk emergency ride home programs, amid other sustainable transport initiatives.  UBC’s continuing growth with such prospective did not come without tradeoffs. In other words reducing one form of transportation results in the increase of other forms. The densification of Main Mall is becoming a growing concern, which is indicative of our aforementioned notion regarding safety on Main Mall.    An Australian report examining the frequency and magnitude of injuries resulting from collisions between pedestrians and cyclists found that pedestrian-cyclist collisions result in equally serious, non-fatal injuries in relation to pedestrian-motor vehicle accidents (Chong et al., 2009) Understandably this sheds light as to why growing congestion on Main Mall can be problematic without appropriate interventions. To address such concerns, UBC has attempted to control Main Mall traffic by implementing traffic-warning signs for cyclists. Currently, there are 7 bicycle traffic signs (BTS) that read “slow - pedestrian priority zone” (Appendix A) on all principal entrances of Main Mall (Appendix B) with plans to install 3 more.   This paper sought to investigate UBC’s current interventions to encourage safe behavior between cyclists and pedestrians on Main Mall. First and foremost, we evaluated the current traffic warning signs, with particular interest regarding its effectiveness and prevalence.   Present literature has extensively examined the multitude of variables that constitute to making a warning label salient. Colored warning labels have shown to elicit higher perceived hazard and readability than achromatic warning labels. (Kline et al., 1993) Moreover, warning labels printed in red yield higher perceptions of hazard than warning labels printed in black, orange, or green. As well, research examining the prevalence of warning signs found that red labels yielded faster detection than black labels.   As the aforementioned literature suggests, color, specifically red, is a key component of making a warning label more salient and precautionary. The purpose of the BTS is to communicate to cyclists a precaution, yet these signs are located on corners just before entering Main Mall making them easy to go unnoticed for someone traveling at high speeds. Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    4 Additionally, the current BTS is depicted by a green ring, which not only adds to the concern of their prevalence, but it may also cause ambiguities in the message it is trying to convey. Given that the color green is often associated with socially constructed meanings of “proceed” and red “yield”, we sought to investigate how different colors on traffic warning signs influence people’s interpretation of speed. We first hypothesized that colors with socially constructed meanings of precaution and attention to detail such as yellow and red respectively, will yield more accurate interpretations of speed in regards to traffic warning signs. Additionally, as a secondary measure, we predicted that the red and yellow conditions would be the more associated with appropriate adjectives such as caution and attention.   Method  Subjects  N=103 participants were originally recruited. After checking for color blindness 3 participants were excluded, and another 14 were excluded for failing a comprehension check, resulting in an end total of N=84 (45 females, 39 males, aged 18-35). All participants were recruited on Main Mall through convenient sampling and 75 were UBC students whilst 9 were not UBC affiliated. All participants were recruited on the basis of willingness to volunteer, gave informed consent, were orally debriefed, and received a small chocolate treat in exchange for their participation. A random generator (Appendix C) was used to ensure random assignment across all conditions.   Conditions  Our independent variable (IV) was the color of the sign, which we operationally defined by manipulating the color of the existing ring on the BTS to fully colored yellow, red, or green, with the original sign as the control (Appendix D).  A between-subjects field experimental design with a structured survey (Appendix E) consisting of 16 questions ranging from demographics, color-blindness, additional data collection, filler questions, target questions, and a comprehension check was given to all participants. All components of the survey were identical across condition except for the color of the BTS sign.   Measure Our dependent variable (DV) was the interpretation of speed at which the fictitious character Sam will ride his/her bicycle after encountering the BTS, which we operationally defined by a 5-point rating scale ranging from 5 km/h to 25 km/h (Appendix F) to gather quantitative data. Additionally, a legend (Appendix G) was provided to show average speed measures of pedestrian walking and cycling speed to assist the comprehension of velocity in this context. Also a mph conversion accompanied each option to avoid confounds for participants not used to the km/h metric. To augment the study’s internal validity, a comprehension check asking participants the destination of the fictitious character controlled against response sets and/or lack of comprehension.  Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    5 The fictitious scenario (Appendix H) was used to measure our target question as it was assumed that individual’s response to a fictitious character’s behavior is analogous to the participant’s conceptualization of the BTS.   Additionally, to examine whether a relationship between the color condition and specific adjectives existed, a secondary measure was conducted. Particularly, the secondary measure investigated which of the adjectives STOP, CAUTION, BEWARE, and ATTENTION, was most associated to each condition in order to see whether the message the sign is trying to convey varied by the color the participant was exposed to.  Procedure  Participants were recruited at 4 designated locations on weekdays between the hours of 1:00-4:00pm at W. Robert Wyman Plaza, Agricultural road and Main Mall intersection, Marta Piper Plaza, and Agronomy road and Main Mall intersection (Appendix I) based on the position of existing signs. Participants were asked if they would like to partake in a survey in exchange for a piece of chocolate. Upon receiving informed consent, participants were randomly assigned to one of the four conditions using a random generator and given a tablet to complete the survey.  To ensure ethical considerations were abided by, participants were informed that if at any moment they wished to withdrawal from the survey, they could do so and all their data would be deleted.   Results   A one-way between subjects analysis of variance (ANOVA) was conducted to examine whether there was a main effect between the four conditions (control, yellow, red, green) and the perceived speed of the fictitious character Sam. A main effect revealed no significant difference between color condition and perceived speed of Sam F(3,80) = 1.97, p=0.12. Given the p value was higher than the .05 alpha levels originally set, it is likely that the results obtained were due to chance. However, the descriptive statistics did show a numerical trend where the yellow (M=9.0, SD=3.08) and red (M=8.86, SD=3.76) conditions complied lower perceptions of speed than the control (M=10.28, SD=4.69) and green (M=11.25, SD=3.69) condition, though only marginally significant. As shown in the graph (Appendix J) the general pattern gives us reason to speculate that the insignificant results may be owing to the smaller than expected sample size obtained.   To measure whether there were any specific significant interactions between all the conditions and the perceived speed, a Tukey’s honestly significant difference test (HSD) was conducted. Again, the post-hoc comparison yielded no significant relationships between the variables. Although non-significant, the mean difference between condition red and green varied the most (Appendix K).  To analyze the results of the secondary measure, a chi-square test of independence was performed examining the relation between the adjectives and the color conditions. However, no significant relationships emerged between adjectives and conditions (9, N=84 = 10.55 p=0.31) (Appendix L). Interestingly, every condition associated caution as the most fitting Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    6 adjective describing the message the sign is trying to convey, followed by attention. Nonetheless, the lack of statistical significance prevents any conclusive remarks to be drawn.    Discussion   There are a number of concerns to be addressed regarding our experimental design. Firstly, the exclusion of 14 participants following the failure of the comprehension check gives us reason to believe that the fictitious scenario may not have been clear. It is possible that participants did not comprehend the scenario thoroughly. Though perhaps a more likely explanation is that participants may not have been engaged or incentivized enough in the survey as it was on the basis of volunteering, which may have led to response sets. Adding to the previous concern, the use of convenient sampling is susceptible to reducing external validity. As the recruitment of the sample was based on volunteers, it is subject to sampling bias, further reducing the generalizability of the results. Furthermore, we have reason to believe the study overlooked peoples understanding of speed measures. Objectively visualizing speed, even in the presence of a legend, is very difficult to conceptualize. It is possible that participants may have just been performing an anchoring bias to the scale that was given. To address such limitations, pilot studies can be conducted to see what facilitates participants understanding of speed, eliminating the need for a legend, so as to alleviate such confines. Previous studies have demonstrated that numerical ranges, accompanied by verbal terms facilitate the understanding of concepts (Budescu, 2014), thus such measures can be taken into consideration for future studies.  The secondary measure was introduced to serve as a manipulation check. Specifically, we were interested in seeing whether the different conditions elicited any variation in terms of conceptualization of the sign as a whole. In other words, we were interested to see whether different conditions provoked any difference in how the sign’s message was interpreted. Nonetheless, the results yielded were insignificant, and there was an over association to the adjective caution relative to the others, demonstrating a possible ceiling effect. This phenomenon may be explained by the work of Klein et al (1993), where it was found that caution induced higher perceived readability in warning labels. Henceforth the adjective choices should be reconsidered as the use of caution may have masked any significant interactions.  As mentioned before, the primary results were marginally significant, therefore our primary hypothesis should not be fully rejected as the numerical trend does show a general pattern. It is imperative that the current results be replicated, perhaps with a bigger sample and addressing the aforementioned limitations, before any conclusions can be drawn. Nevertheless, our secondary hypothesis was rejected as no salient trends emerged and the manipulation was not reliable.   Interestingly, our additional data collection revealed that 81% (Appendix M) of the participants had never encountered the BTS prior to the experiment. Such findings are imperative as there are currently plans to implement 3 more BTS onto Main Mall. It appears Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    7 that these signs are going unnoticed by the general public therefore UBC should be taking into consideration that perhaps the placement of these signs are ineffective.   Recommendations to UBC   Encompassing all the aforementioned notions, we believe there are certain measures UBC can make to improve safety on Main Mall. First and foremost, as we did find a numerical trend for red being more behaviorally compliant than green or the control, we propose UBC to redesign the current BTS into red signs, similar to the ones in our manipulation, as it may serve to elicit more precaution. Also, to further discourse how effective UBC’s current interventions on Main Mall safety are, future studies can take the direction of analyzing not just the color as we have, but the size, placement, font, and illustration to measure what characteristics make the sign more salient.  The placement of the signs should also be reconsidered. As noted before, they are going unnoticed by the general population. Currently the signs are all located on key turning points into Main Mall. As the signs are intended for cyclists, placing the signs on corners is impractical, as they would likely not enter the peripheral vision of the cyclists travelling at high speeds. Instead the signs should be placed before turning into Main Mall and along Main Mall for cyclists to have time to perceive and interpret them appropriately.   However, if amended signs are not feasible in the near future, we propose alternative solutions to work with the existing signs. Main Mall safety is not a commonly addressed problem, thus emphasizing its importance can make students and faculty more aware that such problems exist. UBC can implement campaigns introducing Main Mall safety and instill a frequency illusion in which students and faculty may begin to notice the signs more often if they are aware of its purpose.     Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    8 References  Budescu, D. V., Por, H., Broomell, S. B., & Smithson, M. (2014). The interpretation of IPCC probabilistic statements around the world. Nature Climate Change, 4(6), 508-512. doi:10.1038/nclimate2194 Campus + Community Planning. (n.d.). Getting around the academic core [PDF document]. Retrieved from http://planning.ubc.ca/sites/planning.ubc.ca/files/images/transportation/UBC_SlowCycling.pdf Chong, S., Poulos, R., Olivier, J., Watson, W. L., & Grzebieta, R. (2010). Relative injury severity among vulnerable non-motorised road users: Comparative analysis of injury arising from bicycle–motor vehicle and bicycle–pedestrian collisions. Accident Analysis and Prevention, 42(1), 290-296. doi:10.1016/j.aap.2009.08.006 Kline, P. B., Braun, C. C., Peterson, N., & Silver, N. C. (1993). The impact of color on warnings research.Human Factors and Ergonomics Society Annual Meeting Proceedings, 37(14), 940-940.   Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    9 Appendices  Appendix A Bicycle Traffic Sign      Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    10 Appendix B Map of existing signs provided by the client        Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    11 Appendix C Random Generator App  Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    12 Appendix D Manipulated signs (IV conditions)     Figure 3 Green Condition Figure 2 Red Condition Figure 1 Yellow Condition Figure 4 Control Condition Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    13 Appendix E Survey  Survey links by condition: GREEN CONDITION: https://survey.ubc.ca/surveys/joconde/seeders/ RED CONDITION: https://survey.ubc.ca/surveys/joconde/seeders-red/ YELLOW CONDITION: https://survey.ubc.ca/surveys/joconde/seeders-yellow/ CONTROL CONDITION: https://survey.ubc.ca/surveys/joconde/seeders-ctrl/   Survey screenshots:   Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    14 Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    15 Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    16 Appendix F Dependent Variable      Appendix G Legend     Appendix H Fictitious Scenerio  Dependent Variable 1 (Primary measure of speed perception) Dependent Variable 2 (Secondary Measure of adjective association) Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    17 Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    18 Appendix I Map of where data was collected Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    19  Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    20 Appendix J Graph and SPSS output   Graph 1 Speed Perception Graph  Table 1 SPSS ANOVA output  Table 2 Descriptive Statistics of Speed Perception Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    21 Appendix K Post-hoc Tukey Table  Table 3 Post-Hoc Tukey HSD test for Speed Perception Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    22 Appendix L Chi-Square test output / adjective association graph   Graph 2 Adjective Association Graph Table 4 Chi-Square test of independence output  Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    23 Appendix M Number of people who have seen the sign   Graph 3 Percentage of people who have encountered the sign prior to conducting the survey Main Mall Safety: An Evaluation of the Traffic Warning Sign Colors    24 Appendix N Raw Data of Speed Perception and Adjective Association     Table 5 Speed Perception Raw Data Table 6 Adjective Association Raw Data 

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