Evaluation of mail and in-person contingent value surveys: Results of a study of recreational boaters

Abstract

There is controversy in the literature over the appropriate method for administering the contingent value method (CVM) survey. This research was conducted to determine if there were any differences in responses between the mail and in-person survey methods. Three criteria were used in evaluating the suitability of mail versus in-person surveys: overall response rate; item non-response; and data comparability. Item non-response and the willingness-to-pay function (analysis of covariance regression approach) found more similarities between methods than differences. The mail method had higher individual question response rates than the in-person method for sensitive (income) and CVM (complex, future-oriented) questions. The mail method may be better suited for CVM questions because it allows for contemplation and reduces pressure to an immediate answer. The in-person method may be better suited for recalling past behavior questions. Overall, both methods provided similar results, so it is important to continue to compare the two methods to further establish their validity and replicability.