Rethinking the scope test as a criterion for validity in contingent valuation

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jeem.2004.09.005 Byline: Thomas A. Heberlein (a), Matthew A. Wilson (b), Richard C. Bishop (c), Nora Cate Schaeffer (d) Keywords: Contingent valuation; Validity; Embedding; Scope test; Wolves; Water quality; Biodiversity Abstract: The scope test is widely recommended as a way to evaluate the validity of contingent valuation (CV) studies. We measured contingent values of parts and wholes for four different environmental goods and applied the conventional scope test. In addition, the study design allowed examination of scope relationships for individual respondents. We also used social psychological theory to expand the definition of scope to include attitudinal and behavioral scope. Looking at the individual responses showed that conventional economic scope test results, which depend on comparisons of average values, can hide important relationships that are relevant to the validity of CV studies. We showed that, as a validity test, the conventional scope test can lead to false positives and false negatives. We are led to question the efficacy and cost effectiveness of making scope tests a routine part of validity assessment in applied CV studies. Author Affiliation: (a) Department of Rural Sociology, University of Wisconsin-Madison, 348b Agriculture Hall, 1450 Linden Drive, Madison, WI 53706, USA (b) School of Business Administration, and The Gund Institute for Ecological Economics, University of Vermont, USA (c) Department of Agricultural and Applied Economics, University of Wisconsin-Madison, USA (d) Department of Sociology, University of Wisconsin-Madison, USA Article History: Received 12 July 2002; Revised 27 August 2003; Accepted 30 September 2004