Internet-based travel surveys: selected evidence on response rates, sampling bias and reliability

Due to decreasing response rate to conventional mail questionnaires, transportation researchers should explore the use of alternative means of administration. Internet-surveys provide one of these alternatives. This paper reports some experiences with the use of Internet-surveys in a few studies of different complexity. Experiences suggest that sampling bias is a topic of concern. It also shows however that even quite complex stated adaptation experiments can be conducted reliably using Internet-surveys