Estimation Using Contingent Valuation Data from a “Dichotomous Choice with Follow-Up” Questionnaire: A Comment

Cameron and Quiggin [J. Environ. Econom. Management27, 218–234 (1994)] provide evidence against the use of the standard interval data model and in favor of the more general bivariate probit model. An apparent miscalculation in the estimation process overstates the poor performance of the interval data model for the application reported by Cameron and Quiggin. When the miscalculation is corrected, the data reported by Cameron and Quiggin provide results consistent with Alberiniʹs [J. Environ. Econom. Mangement29, 169–180 (1995)] finding that interval-data models provide robust estimates of mean willingness to pay from dichotomous choice with follow-up contingent valuation questions.