Dealing with internal inconsistency in double-bounded dichotomous choice: an application to community-based health insurance

Contingent valuation method is commonly used in the field of health economics in an attempt to help policy makers in their policy-making decision process. The use of the double-bounded dichotomous choice format results in a substantial gain in statistical efficiency over the single-bounded dichotomous choice format. Yet, there is internal inconsistency with a downward mean shifting in the second responses. Using data from a community-based health insurance survey, this paper aims at testing whether double certainty calibration reduces internal inconsistency in a double-bounded dichotomous choice contingent valuation survey. Results suggest that double calibration significantly reduces internal inconsistency while maintaining the efficiency gain arising from the double-bounded format.