An investigation of preference uncertainty in the contingent valuation study

This study investigates the respondents' preference uncertainty in the dichotomous choice (DC) contingent valuation study for gathering information on willingness to pay (WTP). To this end, we use polychotomous choice (PC) question and DC question with certainty level for two split samples. We find that incorporating preference uncertainty has a significant effect on the WTP estimates and, more importantly, the DC question with certainty level produces more efficient WTP estimate than the PC question.