Testing for Temporal Reliability in Contingent Valuation with Time for Changes in Factors Affecting Demand

We develop a temporal reliability test of the contingent valuation method. Separate random samples were administered the same telephone survey five years apart. In the retest, respondents have less favorable attitudes toward the environment. Given this result, a temporally reliable contingent valuation would find lower willingness to pay. We find that the estimates are temporally reliable. After accounting for attitudes which have changed over the five-year period, values are not significantly different five years apart. This study provides additional evidence that use of the contingent valuation method can provide useful information for environmental policy analysis.