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60 Exhibit 60. Route Characteristics--Phase 1. Route Characteristic Virginia Virginia Portland Portland Florida 2B 38B 14 44 18 Peak frequency (bus/h) 2 4 8 4 4 Off-peak frequency (bus/h) 1 2 5 4 4 Maximum eff. frequency (bus/h) 4 7 38 38 5 Service span (h/day) 16.5 22 20.5 16 19.5 Stops with shelter (%) 13% 29% 34% 30% 23% Stops with bench (%) 15% 26% 47% 41% 75% Street width range (lanes) 29 17 26 16 59 Stops at traffic signals (%) 40% 68% 48% 40% 48% Stops with sidewalks (%) 89% 99% 99% 81% 88% Stops without legal crosswalks (%) 53% 19% 6% 9% 51% Average load (p/bus) 11 14 10 16 ** Average maximum load (p/bus) 18 28 27 25 ** Maximum load (p/bus) 34 44 37 42 ** **Due to a data collection problem, loads cannot be calculated for all trips. A few surveyed trips had standing loads. 4.7 Representation of Survey "camel humps" to have two modes. It is possible for both Results By A Single LOS Grade humps to be an identical percentage of the total distribution, in which case, one cannot report a single LOS result. The automobile, transit, bicycle, and pedestrian surveys The mean is appealing because it always results in a single produced distributions of LOS ratings for any given condi- LOS grade, regardless of the distribution. However the mean tion. However, a distribution of LOS results for any given has a major weakness in that it can reach LOS A or LOS F only mode on any given street is less convenient for decisionmak- in the rare cases when there is almost complete agreement by ers than a single-letter LOS grade as is customary in the the members of the public that the LOS is A or F. Even if most HCM). The HCM does not report the distribution of LOS respondents pick LOS A or F, it takes few dissenters to drag grades for a given situation. The HCM reports a single LOS the mean LOS from A or F (see Exhibit 63). grade for a given situation. This research project was, there- As shown for Distribution #1 in Exhibit 63, even when fore, confronted with the issue of how to convert the distri- 50% of the people choose LOS A, the mean will still be 1.65, bution of LOS grades reported by the public into a single LOS which is closer to 2.00 (LOS B) than to 1.00 (LOS A). The grade for a given situation. "mode" performs as desired for these example distributions, In statistics, various single-value measures can be used to however; we have ruled it out because of its inability to re- represent a distribution. The two most common single-value solve a tie. measures are the "mean" and the "mode" of the distribution. The row labeled LOS 1 converts mean values to a letter The mode is appealing, because it represents the most fre- grade using the same values of LOS A through LOS F that quent LOS response of the public. However, the mode has were used to compute the mean (see Exhibit 64). As can one weakness, in that it is possible for a distribution with two be seen, this approach cannot get LOS A for the mean of Exhibit 61. Route Characteristics--Phase 2, San Francisco. Route Characteristic 38 1 14 30 38 Geary California Mission Stockton Geary Limited Peak frequency (bus/h) 20 10 7 8 9 Off-peak frequency (bus/h) 10 7 7 8 9 Maximum eff. frequency (bus/h) 20 10 27 10 12 Service span (h/day) 20 24 20 24 14 Stops with shelter (%) 44 54% 44% 68% 84% Stops with bench (%) 44 56% 44% 69% 86% Street width range (lanes) 25 24 27 28 28 Stops at traffic signals (%) 58% 91% 54% 63% 75% Stops with sidewalks (%) NA NA NA NA NA Stops without legal crosswalks (%) 2% 1% 1% 3% 0% Average load (p/bus) NA NA NA NA NA Average maximum load (p/bus) NA NA NA NA NA Maximum load (p/bus) NA NA NA NA NA

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61 Exhibit 62. Route Characteristics--Phase 2, AC Transit. Route Characteristic 51 72 72R 218 Broadway San Pablo San Pablo Rapid Thornton Peak frequency (bus/h) 8 4 5 1 Off-peak frequency (bus/h) 8 4 5 1 Maximum eff. frequency (bus/h) 8 4 5 1 Service span (h/day) 19 18 14 15 Stops with shelter (%) 28% 39% 74% 11% Stops with bench (%) 51% 46% 75% 15% Street width range (lanes) 27 25 25 26 Stops at traffic signals (%) 67% 60% 85% 60 Stops with sidewalks (%) NA NA NA NA Stops without legal crosswalks (%) 0% 8% 4% 18% Average load (p/bus) NA NA NA NA Average maximum load (p/bus) NA NA NA NA Maximum load (p/bus) NA NA NA NA distribution #1, but otherwise, performs reasonably for the from a mean of 1.0 to a mean of 2.0; LOS F ranges from a other five example distributions. mean of 5.0 to 6.0. These larger ranges for the extreme LOS The row labeled LOS 2 converts the mean values to a letter grades ensure that extreme LOS grades will be output for grade using a shifted set of thresholds that divide at the mid- distributions where a large portion of the responses are at the point between each LOS value. Unfortunately, this approach extreme LOS grades. results in Distribution #6 being converted to LOS E, instead The LOS3 threshold scheme was tested on the auto video of the desired F and does not solve the problem of producing clip results and was found to produce a reasonable range of LOS B for Distribution #1, when LOS A is the desired result. LOS A through F results for the mean LOS values for the The row labeled LOS 3 shows the results when a com- video clips that were representative of the distribution of the pressed range of thresholds is used to convert the mean values reported LOS results. This threshold scheme was adopted for to letter grades. The compressed range squeezes together the reporting the data collection results and for reporting single- thresholds for LOS B to LOS E, so that wider ranges are avail- letter grade results from the various LOS models developed able for LOS A and LOS F. Under this scheme, LOS A ranges under this research. Exhibit 63. Example Distributions and Mean of Level of Service. LOS Dist 1 Dist 2 Dist 3 Dist 4 Dist 5 Dist 6 A 50% 25% B 35% 50% 25% C 15% 25% 50% 25% D 25% 50% 25% 15% E 25% 50% 35% F 25% 50% Mean 1.65 2.00 3.00 4.00 5.00 5.35 Mode 1 2 3 4 5 6 LOS 1 B B C D E F LOS 2 B B C D E E LOS 3 A B C D E F Exhibit 64. LOS Mean Value Threshold Schemes. LOS Numerical Value LOS 1 LOS 2 LOS 3 Straight Thresholds Thresholds Shifted to Compressed Ranges Midpoints A 1 Mean 1.00 Mean 1.50 Mean 2.00 B 2 > 1.00 to 2.00 > 1.50 to 2.50 > 2.00 to 2.75 C 3 > 2.00 to 3.00 > 2.50 to 3.50 > 2.75 to 3.50 D 4 > 3.00 to 4.00 > 3.50 to 4.50 > 3.50 to 4.25 E 5 > 4.00 to 5.00 > 4.50 to 5.50 > 4.25 to 5.00 F 6 Mean > 5.00 Mean > 5.50 Mean > 5.00