Elicited Choice Probability to Account for Uncertain Responses to Hypothetical Travel Survey Questions

In contrast to the typical discrete choice survey response format, this paper examines Elicited Choice Probability (ECP) data, in which respondents explicitly report uncertain behaviour in hypothetical scenarios. Using survey data from e-bike incentive programs in British Columbia, Canada, we find that most respondents reported more than one possible choice, although they had a strong leading alternative with nearly 80% average likelihood. The ECP data add nuance, but yield similar aggregate choice probabilities (<5%pt difference). A single-choice response format may be preferred to reduce response burden, but analysts should consider the bias it creates toward more-certain alternatives.