There have always been concerns about task complexity and respondent burden in the context of stated choice studies, with calls to limit the number of alternatives, attributes and choice sets. At the same time, some researchers have also made the case that too simplistic a design might be counterproductive. This paper aims to take another look at the effects of design complexity on model results. Specifically, we conduct a study that uses a set of fifteen different designs with varying degrees of complexity and test for differences across designs in terms of substantive results (e.g. WTP indicators) as well as the relative impact of the observed and unobserved utility components. Initial results indicate that the impact of design complexity may be much lower than anticipated, suggesting that respondents can cope adequately with high numbers of attributes, alternatives and choice sets. The implications for practical research are potentially significant, given the reliance, especially in Europe, on binary designs with a very limited number of attributes.
