Response bias in onboard questionnaire surveys


Neil Douglas

Document Type

Conference Paper

Publication Date


Subject Area

planning - surveys


Self completion questionnaires distributed onboard trains or buses offer transport operators and planners a cost-effective way to know their market. However, getting an unbiased sample can be troublesome if passengers with certain characteristics are more difficult to intercept or less willing to complete a questionnaire than others.

This paper first looks at response rate issues and makes referenced to a review by the Transit Research Board (2005) of onboard surveys. The bulk of the paper then uses a 2004 survey of Wellington rail passengers that monitored questionnaire refusal and interception rates to show that systematic biases can exist. A factoring approach is then presented that reduced the bias in the sample.