Driver Assessment of Service Quality on Urban Streets

Abstract

This paper presents the results of a study that compared drivers’ assessments of the performance of urban streets with objective measures of performance, including level of service (LOS). The purpose of the study was to test the ability of LOS to predict drivers’ perceptions of service quality. Seventy-seven automobile drivers rated the service quality of half-mile segments of urban streets as depicted on videotaped scenes from the driver's perspective. Drivers rated 12 to 15 video segments on a six-point scale from very satisfactory to very unsatisfactory. After rating all segments, the drivers selected and ranked from a list of 36 factors the three factors that they considered the most important to quality. The results show that the mean driver rating had statistically significant correlations with operational and design characteristics and aesthetics, including the following variables: travel time, average travel speed, number of stops, delay, number of signals, lane width, the presence of trees, and the quality of the landscaping. LOS, calculated by the Highway Capacity Manual methodology, predicted 35% of the variance in mean driver rating. This finding suggests that LOS does not completely represent drivers’ assessments of performance because drivers perceive the quality of urban street segments in several dimensions, including travel efficiency, sense of safety, and aesthetics.

Analysis and Modeling of Automobile Users’ Perceptions of Quality of Service on Urban Streets

“…Specifically this study was to gather and analyze driver perceptions of the LOS of urban streets and develop models that reflect those perceptions of service. Additional information is available in Flannery et al, who describe efforts undertaken in Phase I of NCHRP 3-70 (1). The steps taken to meet objectives of this research effort included the following:…”

“…Previous studies have consistently shown that travelers are influenced by more than one factor when asked to assess LOS (1)(2)(3)(4)(5). This fact has been echoed in studies addressing transit users', bicycle riders', and pedestrians' perceived LOS (6-8).…”

“…Drivers' perceptions of LOS on arterials are often more related to the efficiency of signal systems than any other factor. Drivers often report lower LOS for trips being made in the off-peak direction that must frequently stop at signals than trips being made in the peak direction that are experiencing much higher volumes and densities, but experience good signal system timing and progression (1,4).…”

“…Preliminary testing was conducted through video presentation methods with 78 participants and limited field testing of six participants. Additional information on the preliminary testing can be found in Flannery et al (1). The factors, included in no particular order, were as follows:…”

Urban Traffic Signal Control Based on Multiobjective Joint Optimization

“…Among them, the most commonly used criteria are delay and number of stops. ese service quality measures are considered to be the most important factors for users to perceive the service level [3]. Webster established a steady-state random delay model for unsaturated traffic flow [4].…”