Response Willingness in Consecutive Travel Surveys

Declining survey response rates have increased the costs of travel survey recruitment. Recruiting respondents based on their expressed willingness to participate in future surveys, obtained from a preceding survey, is a potential solution but may exacerbate sample biases. In this study, the research team analyzes the self-selection biases of survey respondents recruited from the 2017 U.S. National Household Travel Survey (NHTS), who had agreed to be contacted again for follow-up surveys. The team applies a probit with sample selection (PSS) model to analyze (1) respondents’ willingness to participate in a follow-up survey (the selection model) and (2) their actual response behavior once contacted (the outcome model). Results verify the existence of self-selection biases, which are related to survey burden, sociodemographic characteristics, travel behavior, and item non-response to sensitive variables. The team finds that age, homeownership, and medical conditions have opposing effects on respondents’ willingness to participate and their actual survey participation. The PSS model is then validated using a hold-out sample and applied to the NHTS samples from various geographic regions to predict follow-up survey participation. Effect size indicators for differences between predicted and actual (population) distributions of select sociodemographic and travel-related variables suggest that the resulting samples may be most biased along age and education dimensions. Further, the team summarized six model performance measures based on the PSS model structure. Overall, this study provides insight into self-selection biases in respondents recruited from preceding travel surveys. Model results can help researchers better understand and address such biases, while the nuanced application of various model measures lays a foundation for appropriate comparison across sample selection models.


  • English


  • Status: Completed
  • Funding: $162249
  • Contract Numbers:


  • Sponsor Organizations:

    Office of the Assistant Secretary for Research and Technology

    University Transportation Centers Program
    Department of Transportation
    Washington, DC  United States  20590
  • Managing Organizations:

    Center for Teaching Old Models New Tricks (TOMNET)

    Arizona State University
    Tempe, AZ  United States  85287
  • Project Managers:

    Pendyala, Ram

  • Performing Organizations:

    Georgia Institute of Technology, Atlanta

    Georgia Tech Research Corporation
    505 10th Street, Suite 213
    Atlanta, GA  United States  30332
  • Principal Investigators:

    Mokhtarian, Patricia

    Watkins, Kari

  • Start Date: 20200101
  • Expected Completion Date: 20201231
  • Actual Completion Date: 20201231
  • USDOT Program: University Transportation Centers Program

Subject/Index Terms

  • TRT Terms: Research; Travel surveys
  • Subject Areas: Data and Information Technology; Research; Society; Transportation (General);

Filing Info

  • Accession Number: 01848885
  • Record Type: Research project
  • Source Agency: Center for Teaching Old Models New Tricks (TOMNET)
  • Contract Numbers: 69A3551747116
  • Files: UTC, RIP
  • Created Date: Jun 21 2022 9:18AM