Stacey Bricka

Household Travel Surveys with GPS: An Experiment

This paper documents the results of a pilot test done for the Oregon Household Travel Survey. The pilot was designed to enable the Oregon Department of Transportation to determine the role of a Global Positioning System (GPS) in the upcoming survey effort. Specifically, a three-pronged approach was employed. Households were randomly selected for inclusion in the study and then assigned to one of three groups: (a) the traditional survey approach, (b) the traditional approach with GPS, and (c) GPS only. A total of 299 households from the city of Portland, Oregon, were recruited into the pilot, with 235 completing all required activities. A comprehensive evaluation of the similarities and differences in results across the three groups showed differences in respondent burden, completeness of travel details obtained, and costs. Results from this experiment also showed differences in nonresponse bias. The traditional survey had an expected nonresponse for the large households, low-income households, and young adults. Minority participation was on par with census figures. The GPS groups showed higher participation rates for young adults and nonminorities. These data confirmed the general thought that GPS was an effective tool for mitigating nonresponse among young adults. However, the minority nonresponse bias increased significantly with technology, suggesting that other methods would be more appropriate. With regard to completeness of data, geocoding rates are higher for the GPS groups, and there are significant differences in trip departure times, which could affect peak hour and time-of-day modeling. As expected, the costs were higher for the GPS groups, but the expectation is that these costs will fall as processes are standardized across studies and new technologies are introduced.

Do employee commuter benefits reduce vehicle emissions and fuel consumption? Results of fall 2004 survey of best workplaces for commuters

A survey of firms recognized as best workplaces for commuters (BWC) was conducted in the fall of 2004. The purpose of the survey was to determine the difference between the commuting patterns of employees who receive employee commuter benefits, such as those offered by BWCs, and those who do not and to estimate the resulting saving in trips, vehicle miles traveled (VMT), and emissions and fuel consumption. Employers recognized as BWCs in the Denver, Colorado; Houston, Texas; San Francisco, California; and Washington, D.C., metropolitan areas were randomly sampled and recruited into the survey with a combination of telephone and e-mail communications. The results of this survey indicated that when employers provide employees with incentives to commute by means other than driving alone, significant percentages take advantage of these benefits. Comprehensive benefits packages such as those enjoyed by commuters in the BWC group, with financial incentives, services (such as a guaranteed ride home and carpool m...

Factors influencing walking in small urban region

With a population of about 145,000 people, Chittenden County, Vermont, has a metropolitan planning organization (MPO) that oversees approximately

Evaluation of Key Design Elements of Long-Distance Survey of Front Range Travel Counts

30 million annually in transportation investments. Despite the countys small size, nonmotorized travel is an important element of the MPOs transportation planning efforts, as it is for many small and medium-sized communities across the United States. The objective of this research was to identify factors associated with nonmotorized travel, specifically walking trips, within the context of a small urban area. The research used survey, census, and geographic information systems (GIS) data to represent Chittenden County travelers in an analysis of personal, regional, and environmental factors. The results of the research suggest that Chittenden County travelers are represented by both spectrums of the populations income and education. These results contribute to a relatively scarce literature base and provide additional information that, when combined with tools developed previously for small urban areas, may provide planners with insights as they identify and prioritize infrastructure investments to meet the needs of their communities. More research is needed to capture better the travel and built environment effects on walking within a small urban area as well as to determine how to best integrate the demographic characteristics into nonmotorized planning efforts.

An analysis of the factors influencing differences in survey-reported and GPS-recorded trips

An evaluation of two key design aspects of a long-distance survey conducted as part of the 2009–2012 Front Range Travel Counts effort is documented. The Front Range Travel Counts project is a cooperative effort across four adjacent Colorado metropolitan regions to document travel behavior within and across regions. The effort included household, commercial vehicle, and external station surveys. Consistent with the state of the practice in the United States, the long-distance survey was administered as a supplement to the household survey sample. Respondents were asked to record all trips made to a location 50 mi or more from home during the 2-week period before the 24-h travel day. Households reporting no long-distance travel were asked to report details of their most recent long-distance trips, regardless of when the trip occurred. The analysis focuses on two design aspects: (a) the selection of a 2-week recall period, with the request for the most recent trip from those who reported zero long-distance trips, and (b) the definition of a long-distance trip. The results suggest that future surveys should use a longer recall period. In addition, the practice of asking for the most recent trip from only those respondents who reported zero long-distance trips within the recall travel period should be expanded to asking that question of all respondents. Finally, the definition as used resulted in the capture of shorter-distance trips, suggesting that refinement is needed.