Household Travel Survey PreTest Results

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Household Travel SurveyPre-Test Results
Presentation to TRB Travel Survey Methods
Committee By Robert E. Griffiths Technical
Services Director National Capital Region
Transportation Planning Board Metropolitan
Washington Council of Governments January 24,
2007

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Presentation Overview

• Survey Challenges
• Pre-Test Design
• Pre-Test Response Rates
• Characteristics of Respondents
• Address-Based Sampling
• Non-Respondent Follow-Up
• GPS Add-On
• Revision for Main Survey Schedule

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Survey Challenges

• Declining telephone response rates
• Cell phone only households
• Obtaining the participation of lower income,
  minority, younger and no-vehicle households
• Identifying travel substituting activities
  (e.g. teleworking, teleshopping, etc.)
• Incomplete reporting of auto travel
• Measuring non-response

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Survey Pre-Test Design

• Two-stage survey
• Recruitment of Respondents
• Advance Letter with Mail-back HH Questionnaire
• Reminder Postcards
• Telephone Interview to obtain household, person,
  and vehicle data (966 Households Recruited)
• Travel Diary Retrieval
• Captured daily trips and activities
• Telephone retrieval of additional personal
  and travel day diary data (746 Households
  Completed)

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Pre-Test Sample Type Matrix
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Pre-Test Response Rates
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Respondent Characteristics
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Address-Based Sampling

• Randomly Selected Households by Postal Carrier
  Routes for Sample Types 1,23
• Over-sampled higher density, mixed use urban
  areas to ensure a sufficient number of completed
  HH samples in these areas.

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Postal Carrier Routes

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Non-Response Follow-Up Survey

• Telephone NRFS
• Completed Short Interviews with 112 of 895
  Telephone non-respondents (13)
• 12 Zero Vehicle Households
• 2 Cell Telephone Only HHS
• In-Person NRFS
• Completed Short Interviews with 80 of 317 Mail
  Only/No Telephone number Households (25)
• 28 Zero Vehicle Households
• 30 Cell Telephone Only HHS

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GPS Add-On

• GPS
• Recruited 233 Households
• Completed data collection for 174 HHS (75)
• Matched 133 Travel Diary HHS (76)
• Recruited/Matched (57)
• GPS and Travel Diary Trip Counts
• 837 GPS Trips v. 830 Travel Diary Trips Reported
• 15 Under-Reported in Travel Diary
• Typically Omitted Stops in Trip Chain

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Revisions for Main Survey

• Sample Type 2 Design for Main Survey
• Enhanced Telephone Match for Address-Based Sample
• 50 Incentives for HH with Non-Matched Telephone
  Number and small subset of the Matched
• Third Reminder Post-Card
• Internet Options to Schedule HH Survey Interview
• Sample Resting for HH Non-Contacts and Refusals
• GPS Add-on
• In-Person Non-Respondent Follow-Up Interviews

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HTS Schedule