Interviewer Effects in an Environmental Valuation Telephone Survey

We investigate interviewer effects in a random digit dial telephone survey of recycling valuation and behavior. Lack of market experience with environmental goods may cause respondents to be more prone to interviewer effects during valuation surveys. Following previous research in both psychology and survey methodology, we test the direct effects of interviewer gender and race, as well as the interaction effects between interviewer and respondent characteristics. Using data from 132 interviewers and 3,870 interviewees, we apply a hierarchal regression model that accounts for the clustering of interviews and controls for a variety of other confounding variables. We confirm the existence of both direct and conditional interviewer effects. Respondents state higher willingness to pay when interviewed by white or female interviewers. There were also significant interaction effects between interviewer and respondent characteristics. The directions of the interviewer effects are consistent with previous survey research and social psychology theories. We also find “timing effects” related to the time and date of interviews that are not traditionally included in studies of interviewer effects.