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52 For each clip, we defined an indicator variable y as follows: icant if the score for that mode was -3 or +3; this meant that for three of the four common clips for that mode, the differ- y = +1 if the mean rating for the test group is higher than ences in ratings between the test and control groups were sig- the mean rating for the control group, and the difference is nificant and in the same direction. A factor was deemed to be significant. highly significant if the score for that mode was -4 or +4; this y = -1 if the mean rating for the test group is lower than meant that for all four common clips for that mode, the dif- the mean rating for the control group, and the difference is ferences in ratings between the test and control groups were significant. significant and in the same direction. y = 0 if the mean rating for the test group is not signifi- The tested socioeconomic factors are listed in Exhibit 53. cantly different from the mean rating for the control group. Effects of Demographics on Auto LOS Ratings The scores for each of the four control clips for a given mode were added to form a cumulative score for the individ- Significant differences in auto clip ratings are shown in ual factor for that mode. Given that there were four common Exhibit 54. Although there were several significant differences clips for each mode, the score for each factor for a given mode (three of the four clips consistently rated higher or lower), could range from -4 to +4. A factor was deemed to be signif- none was highly significant. Exhibit 53. Test and Control Groups for Socioeconomic and Location Factors. Test group Control group Metro area is Chicago Metro area is San Francisco Bay Area Metro area is New Haven Metro area is College Station All other regions Metro area is San Francisco Bay Area Metro area is Chicago Metro area is College Station All other regions Metro area is College Station Metro area is San Francisco Bay Area All other regions Metro area is College Station All other regions Metro area population 1 million All other respondents Age is 18 - 35 All other respondents Age is 36 - 60 All other respondents Age is 60+ All other respondents Sex is male All other respondents Has a vehicle available All other respondents Has a bike available All other respondents Respondent is employed All other respondents Dwelling unit is single-family home All other respondents Respondent owns the home All other respondents Walks non-recreational > 2 blocks more than once a week All other respondents Cycles non-recreational > 2 blocks more than once a week All other respondents Uses transit more than once a week All other respondents Commutes by auto (drive alone or shared ride) All other respondents Commutes by transit All other respondents Exhibit 54. Significant Differences in Ratings--Auto. Group Group Sample Size Mean Rating Test Control Test Control Differencea Highly Significant Differences None Significant Differences Metro area is New Haven Metro area is College Station 34 38 -1.02 Metro area is New Haven All other respondents 34 111 -0.85 Metro area is New Haven Metro area is Chicago 34 35 -0.84 Has a vehicle available All other respondents 132 13 0.67 Region is College Station All other respondents 38 107 0.50 a Mean of test group rating minus control group rating