In this article, we consider uncertain preferences for non-market goods, but we move away from a probabilistic representation of uncertainty and propose the use of fuzzy contingent valuation. We assume that a decision maker never fully knows her own utility function and we treat utility as a fuzzy number. The methodology is illustrated using data on forest valuation in Sweden. Fuzzy contingent valuation provides estimates of resource value in the form of a fuzzy number and includes estimates obtained using a standard probabilistic approach.
van Kooten, G. C., Krcmar, E., & Bulte, E. H. (2001). Preference uncertainty in nonmarket valuation: a fuzzy approach. American Journal of Agricultural Economics, 83(August), 487-500. https://doi.org/10.1111/0002-9092.00172