An Independent Sample Test of Yea-Saying and Starting Point Bias in Dichotomous-Choice Contingent Valuation

We developed several diagnostic tools to test the convergent validity of two common contingent valuation elicitation procedures. Data were collected from independent samples receiving dichotomous choice and payment card questions. We compared actual with counter-factual responses using deterministic and Monte Carlo methods and we found that WTP distributions and mean values varied by the value elicitation method. We also developed a paired-comparison test for procedure variance which indicated that yea-saying and starting point bias influenced dichotomous choice responses.