The contingent valuation method estimates individuals' willingness to pay (WTP) for nonmarket environmental assets via preferences elicited by either open-ended or dichotomous choice questions. Traditional analysis of such data has tended to ignore zero WTP values, or treat then in a...

The paper examines monetary valuations of lost passive-use benefits associated with damage to a unique environmental resource a national park, elicited through contingent valuation, and compares them with actual donations to the same end, where the latter are interpreted as a quasi-market...