Abstract:The stated preference (SP) method is a way to study people’s preferences through experiment design, often implemented with discrete choice models to estimate the parameters. This paper focuses on deriving the effective sample size for SP experiments which guarantees accurate parameter estimations by proposing an easy-to-operate and comprehensive framework. By applying the framework on an empirical study, a linear model is estimated which reveals that the number of factors and levels, scale of parameters, sample size, and the experimental design strategy have significant impacts on the accuracy of parameters. The effective sample size estimation models of three design strategies are obtained, based on which some practical principles for SP experiment design are proposed.