IMPRECISE PREFERENCES AND SURVEY DESIGN IN CONTINGENT VALUATION

During recent years, the contingent valuation (CV) method has been wid ely used to value non-marketed goods and services. We present the resu lts of a CV study of the value of road safety. We find that stated pre ferences for road safety exhibit considerable imprecision, appear subj ect to various systematic biases, and are insensitive to variations in the quantity and quality of the safety improvements concerned. One br oad implication of these findings may be that, for an important class of goods (of which safety is one example), standard assumptions about the structure of people's preferences may be much too strong. A more s pecific implication, concerning the design and conduct of CV surveys, is that the NOAA Panel's widely cited blueprint for 'good CV practice' may rely far too heavily on assumptions about the precision and sensi tivity of people's preferences.