KY Module 2 Household Travel Surveys Chapter 6 of TS Manual

Survey Planning Agency coordination –Other agencies who rely on local modeling effort –Notification of law enforcement agencies. Critical data elements –E.g. SCAG—transit users, and usage of toll facilities

Unit of Analysis Household? Address? Person? Vehicle?

What is a TRIP? What is an ACTIVITY? What is a STOP? What is a TOUR?

Typical process for current household travel/activity survey implementation Advance letter Telephone recruitment (RDD sample) –Include a few characteristics Mail out diary package Telephone retrieval (limited web retrieval) Thank you postcard or letter

The Death of RDD? Problems with RDD –Low response rates –Will new laws reduce telemarketing so that people will be less reluctant to answer the phone? –Cell phones are not in the RDD frame. 5-7% of hhlds with cell phone only, with young adults being most likely. –2.4% of hhlds in U.S. without phones. (2.0% in metropolitan areas, mostly likely renters)

Alternatives to RDD Getting a good address frame 10-15% “undeliverable” rate What % of addresses are missing? (apartment complexes, new housing) Can you supplement an address frame with employer-provided lists?

Respondent materials: Section 6.6 in the TS Manual Check reading level, 8 th is OK, but 6 th grade is better! Pre-notification letter Brochure Diary materials Reminders Thank you

Pre-notification letter and informational brochure Letter: TS Manual Pages 6-133, Brochure: TS Manual Page NHTS 2001 letter and brochure

Diary design People will NOT read instructions! Single sheet or booklet Vertical or horizontal All of the questions or some of the questions, if telephone retrieval fjfjf

Let’s look at some! Las Cruces Chattanooga Charlotte Tucson SF Bay Area SCAG NHTS

Use a focus group if you try something new!

Incentives for respondents? The best motivation is the belief that the results will be used, and will influence their lives in a positive manner. Small, cash, pre-paid Lottery Gifts (often not perceived as incentive) Choice, including donation to local service agency

The respondent is the “customer” Treat them well. Personalization. Use the method that is convenient for the respondent. Brog method to assign ONE contact person, so that person’s name is on the initial letter, and they make the phone calls, etc.

Field implementation Pre-testing and Pilot surveys: –TS Manual Section 6.7

Monitoring the survey process Help develop the interviewer training materials, especially local knowledge (Place names, company names and nicknames) Participate in the training Make sure that “role playing” is included. Listen to the interviews (if phone) Provide materials to incentivize the interviewers.

Data Cleaning Do not underestimate the time and effort needed for this task. Do not expect your survey contractor to do all the work!

Data cleaning Check geocoding vs. actual address Check travel speed and mode. Check TAZ/TAZ pairs and speeds Check for people traveling together. Check for final return trips to home.

Data analysis

Response Rate Calculate using CASRO or AAPOR standards –Can be as high as 65% response to simple survey of persons. –Can be as low as 20% response to complex activity diary of households.

What do we know about non-respondents? Low-income households and households who are renters. (relevance) Young men, aged Households without vehicles (relevance) Households with 4+ persons (burden) Very high income households (never home)

Ideas to improve response?

Ask fewer questions. Use GPS as a passive data collection method. Ask fewer questions. Use specialized surveys in place of all questions for all people. Give respondents more choice on how and when to participate.

Non-response follow-up studies Even if you have a low response rate, if the sample is not biased, your results should be fine. However, we know from experience that our sample is somewhat biased, especially at the income tails. What we don’t know is how this bias affects our measures of travel and mobility.

Non-response follow-up surveys see A1D10 webpage DRCOG mail-out/mail-back experiment –Small cash incentive included in envelope –Very brief one-page survey –Special survey of hhlds without telephones NCHRP experiment (Spring 2003) Tony Richardson work in Australia –Non-responders are more like early responders, late responders report fewer trips.