RT Journal Article SR Electronic T1 Social Desirability Bias in Contingent Valuation Surveys Administered Through In-Person Interviews JF Land Economics JO Land Econ FD University of Wisconsin Press SP 561 OP 575 DO 10.2307/3147300 VO 79 IS 4 A1 Leggett, Christopher G. A1 Kleckner, Naomi S. A1 Boyle, Kevin J. A1 Dufield, John W. A1 Mitchell, Robert Cameron YR 2003 UL http://le.uwpress.org/content/79/4/561.abstract AB This paper presents empirical evidence of mode effects in contingent valuation surveys. We conducted an on-site, split-sample contingent valuation survey of visitors to Fort Sumter National Monument, South Carolina. All respondents were told that the survey was being conducted on behalf of the National Park Service. We find that WTP for a fort visit is approximately 23–29% higher when the survey is administered through face-to-face interviews with a ballot box rather than being self-administered by the respondent. (JEL Q26, H40)