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30 Thirty-three mid-block locations in Tampa and St. Peters- Florida Department of Transportation (FDOT) to develop a burg were identified to be included in the study. A total of new approach to assess levels of service for automobile, bicy- 96 people were hired by a local temp-worker agency to test cle, pedestrian, and transit modes of travel equally. To even the mid-block crossings. They ranged in age from 18 to 77 years the playing field among modes, they postulated a hierarchy of with a mean of 42.7 years of age. Sixty-eight percent of the transportation user needs based on Abraham Maslow's the- participants were female and 32 percent were male. ory of personality and behavior. This transportation theory The participants were bused to each site and asked to ob- would consist of five levels: safety and security (the most basic serve mid-block crossings for 3-minute periods and then rate need), time, social acceptance, cost, and comfort and con- the difficulty of crossing on a six-point scale (A to F). Cross- venience (the least basic need). Perone et al. [64] provide an ing difficulty was defined as the risk of being hit by a vehicle, update to this FDOT work in their final project report. Their the amount of time to wait for a suitable gap in traffic, pres- final multi-modal model is based on the work of Maslow as ence of a median or other refuge, parked cars, lack of an ac- well as Alderfer and his Existence, Relatedness and Growth ceptable (wide enough) traffic gap, or anything else that (ERG) Theory. The project provides evidence for the exis- might affect crossing safety in determining the crossing diffi- tence of such a hierarchy in which most participants chose culty. It was stressed to the participants to only consider their Existence over Relatedness over Growth needs and found that crossing difficulty, not for others that might cross the road- a lower motivator need not be substantially satisfied before way. A total of 767 observations were made. Results of the one can more onto higher motivators. study showed that the level of crossing difficulty tended to in- Dissatisfied with inadequacies of auto-based (i.e., HCM) crease with the width of painted medians, signal spacing, and and other multi-modal measures of LOS for project-level en- turning movements, and that the presence of pedestrian sig- vironmental impact reviews, Hiatt [65] reports on the City of nals lowered the perception of crossing difficulty. The pres- San Francisco's efforts to develop an alternative method for ence of pedestrian signals and cycle length were also shown to use in that city's urban, multi-modal context. The paper dis- be statistically significant. The final linear regression model cusses a proposed alternative to modal-based LOS measures had an R-square value of 0.34 and contained 15 variables re- that calculates automobile trips generated that would vary by lating to traffic volumes, turning volumes, age of pedestrian, land use typology and parking supply, and reflect expected average vehicle speed, crossing width, presence of pedestrian mode shifts associated with projects such as bicycle or transit signal, cycle length, and signal spacing. lanes. Chu, Guttenplan, and Baltes [62] placed 86 people at Winters et al. [66] looked at various methods for achiev- 48 intersection and mid-block locations and asked them to ing comparability of LOS significance across modes. They identify one of six routes they might take to cross the street. identified the issue of different letter grades implying "trav- They obtained a total of 1,028 observations of 4,334 cases. eler satisfaction" for the various modes. LOS D for highway They fitted a 2-level nested logit model to the survey re- facilities is considered satisfactory by many public agencies sponses. The first level predicted whether they would cross for facility planning purposes. However, LOS D for bicycles at an intersection or cross mid-block. The lower level then may be a facility that only the hardiest bicyclists dare use. predicted which of various mid-block crossing routes they LOS D may not be a satisfactory level of service for planning might pick. The significant explanatory factors were starting bicycle facilities. or ending point of trip, walking distance, crosswalk marking, The authors conducted a literature review and then devel- and presence of traffic or pedestrian signal. Less significant oped various options for reconciling the meaning of LOS factors included in the model were traffic volume and shoulder/ across modes to an advisory panel of stakeholders consisting bike lane width. Delay at the signal was not an explicit factor. of potential technical users of the LOS methodology for state The presence of a signal positively encouraged crossings at and local agency facility planning purposes. the intersection. The authors looked at how the various modal measures of LOS addressed different degrees of travelers' needs. Some, like FDOT's bicycle and pedestrian LOS measures are based 3.5 Multimodal LOS Research on travelers' perception of safety, which is a higher priority Recent work on developing a method to estimate multi- need than "convenience" which is implicit in the auto LOS modal LOS appears to wrestle with the issue of defining what measure of speed. LOS means in a multi-modal context. Several of these studies They suggested offsetting the scales against some standard are working to establish a "common denominator" that can of traveler satisfaction, i.e., using a sliding scale. LOS D is the be used to compare the performance of different modes with- threshold of acceptability for auto, but LOS C is the thresh- out unintentionally favoring one mode over the others. old of acceptability for bicycles. The advisory panel accepted Winters and Tucker [63] reported on their work for the (with reservations) this slide rule method, but recommended

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31 that additional data be acquired for identifying common de- on arterials. FDOT was concerned that the HCM assessment nominators across modes for level of service. of arterial LOS focuses primarily on the automobile; LOS des- Crider, Burden, and Han [67] developed a conceptual ignations for pedestrians and bicycles are based primarily on framework for the assessment of multimodal LOS at inter- facility crowding. Recent research, however, has found that sections and bus stops for the transit, bicycle, and pedestrian quality of service for pedestrians and bicyclists depends more modes. For transit, a bus stop LOS measure based on fre- on lateral separation of the mode, motorized vehicle volumes quency and pedestrian accessibility was recommended. For and speeds, and transit frequency of service. bicycles and pedestrians, intersection LOS measures based on This paper presented the methods used by FDOT to calcu- conflicts, exposure, and delay to through movements were late LOS for bicycles, pedestrians, and transit. For each mode, recommended. Various techniques for surveying traveler a score is computed using various characteristics of the road- perceptions were considered and a selected set of techniques way and traffic; LOS thresholds are used to transform the was recommended. scores into LOS measures. Bicycle LOS depends primarily on Dowling [68] developed a methodology for assessing mul- effective width of the outside through lane (including bicycle timodal corridor level of service involving parallel facilities. lane width) and the volume of motorized vehicles. Pedestrian The methodology generally relied on existing FDOT methods LOS depends on sidewalk presence, roadway widths, separa- for estimating facility LOS and created new LOS measures to tion from traffic, and vehicle speeds and volumes. Transit address aspects of corridor LOS not covered by current meth- LOS depends on service frequency, adjusted for pedestrian ods. New LOS measures included difficulty of crossing of LOS and hours of service per day. freeway LOS, freeway HOV lane LOS, rail LOS, off-street The methods described in the paper are primarily segment- bike/pedestrian path LOS, and a congestion-based measure of based; additional research is under way to expand the appli- auto LOS (i.e., the ratio of congested speed to free-flow speed). cability of the method (e.g., to area wide and point-level Phillips, Karachepone, and Landis [69] documented the analyses). Separate LOS measures are provided for the differ- results of a project to develop planning analysis tools for es- ent modes; but FDOT does not provide a single LOS measure timating level of service for transit, pedestrian, and bicycle that combines all modes because doing so could mask the ef- modes. This research built on prior research by Sprinkle Con- fect of less-used modes. A key feature of the method is that it sulting and Kittelson & Associates and was adapted for use in captures interactions between modes, including the interac- the Florida Quality/Level of Service Handbook. tions of pedestrians and transit. The Phillips, Karachepone, and Landis report defined Qual- Guttenplan et al. [71] describes the development of a ity of Service as "The overall measure or perceived perform- multimodal areawide LOS methodology based on the FDOT ance of service from the passenger's or user's point of view." Q/LOS Handbook procedures for individual facilities and The report defined Level of Service as "A range of six desig- modes. The steps of the methodology are nated ranges of values for a particular aspect of service, graded from "A" (best) to "F" (worst) based on a user's perception." 1. Define major modal facilities within study area. It defined Performance Measures as "A quantitative or quali- 2. Determine percentage of households and employment lo- tative factor used to evaluate a particular aspect of service." The cated within service areas of each major modal facility. distinction between "service measures" and "performance The percentage of households and employment served by measures" was that service measures represented only the pas- the major modal facilities sets the ceiling for the best pos- senger or user's point of view, while performance measures sible areawide LOS for the mode. could consider a broader range of perspectives, especially those 3. Determine modal LOS for each major modal facility. of the public agency. 4. Compute mean modal LOS across all major modal facili- Guttenplan et al. [70] discussed methods developed by ties in the study area. FDOT to determine level of service to through vehicles, 5. Select the lower of mean modal facility LOS or the per- scheduled fixed-route bus users, pedestrians, and bicyclists centage households and employment served LOS value.