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87 the dependent variable or because of their colinearity with Ped Density LOS = The letter grade level of service for side- more strongly correlated variables. Also, variables such as walks, walkways, and street corners based traffic volume, sidewalk width, and signal delay, are compo- on density nents of the segment LOS or the intersection LOS, so we did Ped Other LOS = The letter grade level of service for the not model them independently. urban street based on factors other than Several variables were evaluated for inclusion as additional density terms in the model. Frequency of unsignalized conflicts (in- tersections and driveways) per mile was tested for its correla- Pedestrian Density LOS Model tion and significance to the arterial LOS for pedestrians and for Sidewalks, Walkways, Street Corners was not found to be a significant factor. Additionally, the density of pedestrians on the sidewalk (the current HCM The methods of Chapter 18 of the HCM are used to com- measure of LOS) was not found to be significant for this pute the pedestrian density for the sidewalks and the pedes- model, within the low range of density values available in the trian waiting areas at signalized intersection street corners. video clips. The LOS thresholds given in that chapter for these facilities are used to determine the level of service. The thresholds for sidewalks and walkways are given in Exhibit 93. 8.2 Recommended Pedestrian LOS Model Pedestrian Other LOS Model The proposed pedestrian level of service predicts the mean The pedestrian LOS for the facility that is representative of level of service that would be reported by pedestrians along or non-density factors is computed according to either of the across the urban street. The average pedestrian LOS for the two models below: urban street facility is a function of the segment level of serv- Pedestrian Other LOS Model 1 ice, the intersection level of service, and the mid-block cross- ing difficulty. OtherPLOS (#1) = (0.318 PSeg + 0.220 PInt + 1.606) * (RCDF) (Eq. 34) Pedestrian Other LOS Model 2 Overall Pedestrian LOS Model OtherPLOS (#2) = (0.45 PSeg + 0.30 PInt The overall pedestrian level of service for an urban street is + 1.30) * (RCDF) (Eq. 35) based on a combination of pedestrian density and other fac- tors. The level of service according to density is computed. Where Then the pedestrian LOS according to other factors is com- OtherPLOS = Pedestrian non-density (other factors) LOS puted. The final level of service for the facility is the worse of PSeg = Pedestrian segment LOS value PInt = Pedestrian intersection LOS value the two computed levels of service. RCDF = Roadway crossing difficulty factor Ped LOS = Worse of (Pedestrian Density LOS, The first model provides the better statistical fit with the Ped Other LOS) (Eq. 33) video lab data. However, this model does not produce LOS F Where for the streets in the video clip data set. The second model is Ped LOS = The letter grade level of service for the a manual modification of the parameters of the first model so urban street combining density and other that the second model will produce a full range of LOS A to F factors. for the streets in the video clip data set. The constant was Exhibit 93. Pedestrian Walkway LOS (Density). LOS Minimum Pedestrian Space Per Person Equivalent Maximum Flow Rate per Unit Width of Sidewalk A > 60 SF per person 300 peds/hr/ft B >40 420 C >24 600 D >15 900 E >8 1380 F 8 SF > 1380 Source: Exhibit 18-3 HCM 2000 [110]