2013 Session: 615

• Examining Trip Underreporting Behavior Using GPS-Assisted Household Travel Surveys
  Abstract: Trip underreporting has been a persistent and well known problem with household travel surveys. This paper primarily focus on investigating the pattern and magnitude of trip underreporting behavior by comparing travel data from diary-based and GPS-assisted surveys, and exploring a wide range of demographic and travel related characteristics in the aim of gauging trip misreporting. This study employs the New York metropolitan region household travel survey, which contains about 1,900 (10% of the entire sample) households participated in the GPS-assisted prompted recall method instead of diary-based approach. Detailed trip underreporting phenomenon by trip purpose, mode, trip length, trip chaining, and time-of-day, etc. is explored across various socioeconomic and demographic characteristics, such as person type, gender, household size, and household income, etc. This paper sheds lights on the multi-faceted dimension and the associated factors of trip misreporting, which will leads to better methods to account for misreporting in travel surveys and to incorporate correction factors in model estimation.
  Authors: Jin, Xia; Wu, Jingcheng; Asgari, Hamidreza; Argote, Jorge A.
  Authors: Jin, Xia; Wu, Jingcheng; Asgari, Hamidreza; Argote, Jorge A.
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-1780
• Exploring Commuting Flexibility with GPS Data: Case Study in Beijing
  Abstract: This paper explores the Intra-personal day-to-day variability and flexibility of commuting behavior. Commuting behavior has been widely investigated based on questionnaire data from trip and activity dairy surveys. There has been very limited research focused on day-to-day variations in commuting behavior. The rapid development of location-based technologies and ICTs brings new opportunities for better insight into commuting with tracking data which has higher space-time accuracy and is easier to collect long-term data. In transitional urban China, the residents¡¯ commuting behavior, including travel distance, travel duration, travel mode and route choice varies greatly, and patterns could be rather complex. To better understand complex patterns of commuting behavior, this paper uses the concept of commuting flexibility. Four dimensions are defined on the basis of existing literatures and actual situation, and are measured by the GPS data for day-to-day travel. Data for this study are drawn from a 2010 Beijing activity-travel survey, including 100 residents in two selected suburban communities. We combine 7 days GPS tracking data and activity-travel dairy to explore residents¡¯ commuting flexibility and commuting patterns. The time geography framework is used to visualize weekly commuting patterns and show four dimensions of commuting flexibility synthetically. The paper tries to explain the commuting flexibility from the perspectives of institution, planning, policy and culture.
  Authors: Shen, Yue; Chai, Yanwei
  Authors: Shen, Yue; Chai, Yanwei
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-1951
• Tablet and Web-Based Regional Airport Travel Survey with Synchronized Bluetooth Traffic Data Collection
  Abstract: This paper provides an overview of the comprehensive data collection effort completed at two Phoenix airports in order to update and recalibrate ground-access travel sub-models. Central to this effort was an advanced, tablet-based air passenger survey that used mapping software to collect air passenger trip diaries with detailed origin-destination location information. This paper discusses the airport survey design, sampling plan, data expansion plan, and survey instruments as well as Bluetooth® Automatic Wireless Address Matching origin-destination data and other traffic data collection. It discusses challenges faced and lessons learned. The Maricopa Association of Governments (MAG), the metropolitan planning organization for the Phoenix metropolitan area, carried out the comprehensive airport data collection effort in collaboration with the City of Phoenix, City of Mesa, Phoenix Sky Harbor International Airport, and Phoenix-Mesa Gateway Airport.
  Authors: Gorton, Michael; Livshits, Vladimir; Kuppam, Arun R.; Brown, Ted; Tierney, Kevin; DeBoer, Kathy
  Authors: Gorton, Michael; Livshits, Vladimir; Kuppam, Arun R.; Brown, Ted; Tierney, Kevin; DeBoer, Kathy
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-2246
• Examining Differences Between Travelers’ Revealed Versus Actual Travel Time Savings
  Abstract: Revealed preference surveys are one of the most common ways to obtain information on how travelers use a given transportation facility. In a revealed preference survey the respondents are asked questions related to their recent travel. In a survey conducted in 2010 on Houston Katy Freeway travelers, respondents were asked about their travel experience using the new Katy Freeway Managed Lanes (MLs). They were asked if they experienced any travel time savings by using the MLs. This study examined any difference between their perceived and actual travel time savings. This study found that travelers overestimate the travel time savings they experience by traveling on the MLs. The magnitude of misperception varied with individuals with an average value of 11 minutes. Linear regression models were fit to model the misperception of the travel time and found that both trip characteristics and respondent socio-economic characteristics had an effect on the magnitude of misperception of travel time savings. Respondents’ trip purpose, age, gender, and income were found to be significant predictors of how well they estimated their travel time savings.
  Authors: Devarasetty, Prem Chand; Burris, Mark W.; Huang, Chao
  Authors: Devarasetty, Prem Chand; Burris, Mark W.; Huang, Chao
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-3202
• Imputing Trip Purpose Based on GPS Travel Survey Data and Machine Learning Methods
  Abstract: In the recent decades, increasing number of travel researchers show interest in travel behavior research based on GPS/GIS technology. The challenge of successfully utilizing GPS-based data is the efficient post-processing method that could generate the essential components as accurately as possible in travel behavior researches such as travel time, trip purpose, travel mode, and trip length. This paper concentrates on part of the GPS data post-processing: trip purpose derivation, and explores the feasibility of automating trip purpose detection employing machine learning method with geospatial location data, the land use data, and the in-practice GPS-based survey conducted by University of Minnesota. Furthermore, it evaluates the impacts of different land use coding methods based on polygon-level, geo-coded home/work locations and Point of Interest (POI) land use data combined with different machine learning methods including decision tree, support vector machine and metalearner. A heterogeneous sample of 2238 trip records with decoded 7 trip purposes is employed. Results show that under all the machine learning methods, the cluster-based land use coding method is exceeded by the closest POI land use coding method, while amongst the three machine learning methods, the metalearner has the best performance to classify the trip purpose. Based on the metalearner and the data set using the closest POI land use coding method, the highest classification accuracy 80.5817% can be achieved.
  Authors: Lu, Yijing; Zhu, Shanjiang; Zhang, Lei
  Authors: Lu, Yijing; Zhu, Shanjiang; Zhang, Lei
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-3177
• Surveying Hard-to-Reach Groups: Is a Cell Phone Survey the Solution?
  Abstract: Montreal’s Origin-Destination (O-D) surveys have traditionally used residential telephone listings as a sample frame. The population covered by these lists was estimated at around 90% in 2002; however the increase of cell-phone-only households has eroded its coverage. A direct consequence of this technological shift is the increasing difficulty in reaching young people aged 20 to 34 and single-person households; it is estimated half of 20 to 34 year olds reside in a cell-phone-only household. In March 2012, 464 surveys were completed with cell-phone-only households as part of the continuous O-D travel survey. 56% of respondents of the cell-phone-only sample were in the 20-to-34 age bracket. Differences exist between both samples; cell-phone-only households own fewer cars, have lower incomes, are more likely to live in central neighborhoods and are less likely to have children under 15 living in them. However, when comparing two sub-samples with the same characteristics, no significant differences were found, except the average number of cars per household and the proportion of households with a lower household income. Challenges in surveying cell-phone-only households include the impossibility of controlling the sample geographically until after the survey has begun and its high costs; each completed survey costs 3 times as much as one completed using the landline sample.
  Authors: Cerda, Assumpta
  Authors: Cerda, Assumpta
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4327
• Data Cleaning in Activity and Travel Surveys: Methodology Applied to Walk Trips
  Abstract: Activity-based household travel surveys are becoming much more common as states and metropolitan regions contemplate advancing their travel behavior forecasting abilities. Such activity and travel surveys are valuable for the estimation and calibration of activity-based travel demand forecasting models. Before travel survey records can be used, they must be edited using data cleaning processes that identify, reject, and/or correct internal inconsistencies, miscoded information, and other errors. Literature on travel survey data cleaning is sparse, and few travel survey data cleaning standards exist beyond ad-hoc rules of thumb. This paper presents a possible methodology for improving on data cleaning rules of thumb by borrowing statistical methods, especially from the field of robust statistics. The methodology was applied to the walk trip records of a household activity and travel survey conducted during 2011 in the Portland, Oregon, region. First, indicator variables were constructed to flag suspect walk trips. Next, visual inspection of the highest-ranking 5% of suspect walk trips was performed. The methodology identified 29 walk trips with an incorrect mode, 19 location errors, 39 trips with travel time errors, and 6 walk trips with inaccurate trip purposes. After correcting the mode errors and removing the trips with location errors, key walk calibration statistics were more reasonable, demonstrating the usefulness of a statistically-derived data cleaning methodology. Finally, the paper concludes with recommended foci for data cleaning efforts of activity-based household travel surveys.
  Authors: Singleton, Patrick A.
  Authors: Singleton, Patrick A.
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4443
• Know Your Audience: Conducting Effective Travel Diary Surveys at Colleges and Universities
  Abstract: Despite being frequently underrepresented in travel diary survey efforts, colleges and universities – depending on their size, geographic location, and student body composition – can be major contributors to travel demand in their respective regions; therefore, researchers ought to study travel patterns and behavior at these educational institutions more often and in greater detail. This paper uses two case studies to detail the approach, design, and methodology of conducting travel diary surveys at colleges and universities. The first case study focuses on one stand-alone travel diary of students, faculty, and staff at Arizona State University, one of the largest universities in North America. The data collected (14,464 valid responses) will help support the Maricopa Association of Governments’ activity-based travel demand model. The second case study examines the survey administered at eight colleges (7,923 valid responses in total) across the state of Utah that was linked to the larger statewide household diary survey. This paper highlights the similarities and differences between the two approaches, notes the relative cost-effectiveness of both methodologies, and discusses the value of these datasets to regional travel demand modelers and strategic planners at educational institutions.
  Authors: Kerrigan, James; Greene, Elizabeth R; Pendyala, Ram M.
  Authors: Kerrigan, James; Greene, Elizabeth R; Pendyala, Ram M.
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4843
• Innovative Approaches for an Interactive Stated-Choice Survey
  Abstract: Stated preference surveys provide an excellent source of information for the development and targeted implementation of transport planning measures. This paper describes two innovative methods used in a study of road pricing’s impact on travel behavior in Austria. First, the research used an innovative process to generate realistic route choice alternatives for use in the survey. These alternatives were generated using online resources (e.g. Google Maps) and created alternatives that were familiar to the survey respondents. Second, the research used three different methods for data collection: tablet computer assisted interviews, web assisted interviews and traditional pencil and paper interviews. The use of these different methods helped the researchers obtain a representative sample of the Austrian population. While tablet-assisted interviews appealed to the younger generation, older people were incorporated with the pen-and-paper method. Additionally, via systematic sampling people from “hard-to-reach” groups became accessible. An important benefit of using the tablet-based data collection was that survey participant demographic data was available in real time enabling the survey manager to direct surveyors to target underrepresented groups immediately. The tablet computers also improved data quality and slightly increased willingness to participate in the survey.
  Authors: Reiter, Thomas; Völkl, Andrea; Fellendorf, Martin
  Authors: Reiter, Thomas; Völkl, Andrea; Fellendorf, Martin
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-0272
  Practice-Ready: Yes
• Examining Estimation Bias and Efficiency for Pseudo Panel Data in Travel Demand Analysis
  Abstract: Pseudo panel data have been increasingly applied in travel demand analysis to investigate the long-run travel demand when genuine panel data are unavailable. However, conventional estimation techniques have been used typically without a careful consideration to some unique properties of pseudo panel data. This paper shows that ignoring properties such as time-varying cohort effects, a small number of constructed cohorts, large between-group variance, and trade-offs between cohort sizes and number of cohorts potentially leads to estimation bias or inefficiency not observed in genuine panel data. The methodology of a Monte Carlo experiment is used with scenarios that are designed to generate, under conditions of limited observations, various data possessing pseudo panel data characteristics, and evaluates the performances of various estimators using the simulation results. The main research findings are that the large between-group variation of the exogenous variable and the variance of fixed group effects in pseudo panel data are the primary causes of estimation bias and inefficiency. Other factors including the cohort size and potential non-spherical errors have a smaller impact on the estimators’ performances. An empirical application using Sydney Household Travel Survey data is also presented to illustrate the simulation findings.
  Authors: Tsai, Chi-Hong; Leong, Waiyan; Mulley, Corinne; Clifton, Geoffrey Tilden
  Authors: Tsai, Chi-Hong; Leong, Waiyan; Mulley, Corinne; Clifton, Geoffrey Tilden
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-0538
  Practice-Ready: Yes
• Quantifying Key Errors in Household Travel Surveys
  Abstract: Identifying and minimizing potential errors in household travel surveys can facilitate collecting more representative and accurate data. This paper presents how sampling, non-coverage, non-response, and measurement errors work their ways into surveys through a comparison of two recent travel surveys with census data. The 2009 National Household Travel Survey (NHTS) Add-On in Virginia was implemented using a comprehensive survey instrument and Random Digit Dialing (RDD). The 2008 National Capitol Region Household Travel Survey collected behavioral data with a concise instrument, while adopting Address-Based (ADD) sampling. Focusing on a common area of Northern Virginia, this study examined differences in socio-demographics and travel behavior of the extracted samples (N=597 and N=3,581, respectively). Results show that the ADD method collected data on more single-person households, younger individuals, and Hispanics/Mexicans, which are generally identified as hard-to-reach groups. A comparison of the two unweighted samples with census data shows that the ADD sample was more representative of the population and area, partly because of the inclusion of mobile phone only households (28%), which are not covered in RDD. To quantify a measurement error, rigorous statistical models were estimated in terms of reported trip frequency. Results show that NHTS captured 10% more trips, partly due to diary instructions and the presence of walking/biking questions in the instrument. The details of other errors and implications for reducing key survey errors are discussed.
  Authors: Son, Sanghoon; Khattak, Asad J.; Wang, Xin; Agnello, Paul Thomas; Chen, Juyin
  Authors: Son, Sanghoon; Khattak, Asad J.; Wang, Xin; Agnello, Paul Thomas; Chen, Juyin
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-0552
  Practice-Ready: Yes
• Sampling Design and Data Collection for NEWPATH Survey
  Abstract: The design of sampling and data collection for the NEWPATH survey, conducted in the Region of Waterloo, Ontario, are presented as a case study in design of a complex survey of health behaviors, including travel patterns, objectively- and subjectively-measured physical activity behaviors, diet-related behaviors, and health outcomes. Features of this design include stratification of the sample with respect to neighborhood walkability, household income and household size with allocation to achieve high statistical power, and carrying out sampling in phases to achieve cost efficiencies. The final data set is approximately representative of the population in terms of demographic measures, and survey weights compensate for biases introduced by oversampling of high- and low-walkability areas as well as differential non-response.
  Authors: Thompson, Mary; Frank, Lawrence D.; Minaker, Leia; van Loon, Josh; McSpurren, Kathleen; Fisher, Pat; Raine, Kim D.
  Authors: Thompson, Mary; Frank, Lawrence D.; Minaker, Leia; van Loon, Josh; McSpurren, Kathleen; Fisher, Pat; Raine, Kim D.
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-2006
  Practice-Ready: Yes
• Using Activity Space to Define and Analyze Long-Distance Passenger Travel
  Abstract: The definition for long distance travel is constantly evolving and widely varying between organizations and areas. The classification for long distance travel mostly deals with having a basic distance threshold for which trips are classified as long distance or normal travel. Those definitions that do not have a basic distance threshold instead use a qualitative definition that is difficult to use in modeling environments. This paper creates a new classification system for long distance travel, using a hard quantitative measure that is not simply a distance threshold. Instead, individual location density, activity space and trip length (miles) are considered. Using GPS panel data, the user’s normal activity space is developed. Then, a long distance trip classification is defined, dependent upon the distance traveled outside of this normal activity space. Results show that the new approach delivers a larger percentage of long distance trips, compared to the NHTS definition, where 50 miles from home is determined as long distance. The distance based approach disqualifies trips that are taken frequently, such as commute trips, and include those that are shorter and lie outside the individual’s normal travel pattern. With this in mind, the activity space approach proves to be an advancement to the strictly distance based definition currently used by the National Household Travel Survey. Finally, suggestions for future advancements as well as the next-best qualification system are presented. The activity space approach proves to be an advancement to strictly distance based definitions for long distance travel currently in use by the National Household Travel Survey.
  Authors: Zhang, Lei; Krause, Cory
  Authors: Zhang, Lei; Krause, Cory
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-3079
  Practice-Ready: Yes
• Design and Implementation of Internet-Based Household Activity Scheduling Survey in Cairo, Egypt
  Abstract: This paper reports on the design and implementation of an internet-based survey that focuses on household activity scheduling in Cairo, Egypt. The survey is referred to as Internet-based Daily Activity Scheduling of Household Activities (IDASHA). The main emphasis of the survey was on different types of household interactions and coordination over a multiple-day period. As well, the survey collected detailed information about ICT usage and the role that telecommunications play in household interactions in the planning and scheduling process. The survey was conducted over one week during the months of March to May, 2009. The final sample size included 42 households of married couples (i.e. 84 adults). The survey was evaluated according to several criteria and it was shown to provide a rich source of data while minimizing the burden on the survey respondents. Moreover, statistical analyses were carried out to investigate several issues such as time allocation behavior, weekly household interactions in activity participation, and the development of a “horizon index” that shows how far ahead in time an event was planned.
  Authors: Mosa, Ahmed Ibrahem; El Esawey, Mohamed
  Authors: Mosa, Ahmed Ibrahem; El Esawey, Mohamed
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4127
  Practice-Ready: Yes
• Long-Distance Travel: Update from 2011 Web-Based Travel Survey for California High-Speed Rail Authority
  Abstract: Information on long distance travel is crucial for interregional and statewide travel forecasting. Unfortunately, there is a dearth of information regarding the frequency and travel purposes of long distance travel. Long distance trips, often defined as travel to locations more than 50 miles from the travelers home location, are made with much less frequency than the daily travel typically collected in household travel surveys. Indeed, while daily trip rates of three to four trips per person per day are typically reported for urban areas, daily long distance trip rates of two to three trips per person per year are typical. Thus, typical household survey procedures of collecting all travel for members of respondent households over a one to two day period are not adequate for the analysis of long distance travel unless survey sizes are extremely large.In May and June 2011, Cambridge Systematics (CS) conducted a web-based long distance travel survey to collect information on long distance travel characteristics of California residents. The data were used to revalidate the California High Speed Rail Ridership and Revenue Model (CAHSR3M) used to provide forecasts for California High Speed Rail Authority (CAHSRA) planning of the project. The actual survey was conducted by Harris Interactive (Harris) using Harris’ web-based polling process and their on-line panel of California residents.This paper provides a brief overview of the survey purpose, design, expansion, and results. The survey, which collected nearly 12,000 usable samples, was designed, conducted, and summarized in less than three months.
  Authors: Bierce, Eric; Kurth, David L.; West, Ron
  Authors: Bierce, Eric; Kurth, David L.; West, Ron
  Year: 2013
  Document Type: Paper
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-5271
  Practice-Ready: Yes
• Exploring Commuting Flexibility with GPS Data: Case Study in Beijing
  Authors: Shen, Yue
  Keywords: poster presentation; poster design; poster template
  Authors: Shen, Yue
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-1951
• Tablet and Web-Based Regional Airport Travel Survey with Synchronized Bluetooth Traffic Data Collection
  Authors: Gorton, Michael
  Authors: Gorton, Michael
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-2246
• Examining Differences Between Travelers' Revealed Versus Actual Travel Time Savings
  Authors: Burris, Mark
  Authors: Burris, Mark
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-3202
• Design and Implementation of Internet-Based Household Activity Scheduling Survey in Cairo, Egypt
  Authors: El Esawey, Mohamed
  Authors: El Esawey, Mohamed
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4127
• Long-Distance Travel: Update from 2011 Web-Based Travel Survey for California High-Speed Rail Authority
  Authors: Kurth, David
  Authors: Kurth, David
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-5271
• Examining Estimation Bias and Efficiency for Pseudo Panel Data in Travel Demand Analysis
  Authors: Tsai, Chi-Hong
  Authors: Tsai, Chi-Hong
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-0538
• Quantifying Key Errors in Household Travel Surveys
  Authors: Son, Sanghoon
  Authors: Son, Sanghoon
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-0552
• Imputing Trip Purpose Based on GPS Travel Survey Data and Machine Learning Methods
  Authors: Lu, Yijing
  Authors: Lu, Yijing
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-3177
• Data Cleaning in Activity and Travel Surveys: Methodology Applied to Walk Trips
  Authors: Singleton, Patrick
  Authors: Singleton, Patrick
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Data and Information Technology
  Session: 615
  Paper Number: 13-4443