How Much of Interviewer Variance Is Really Nonresponse Error Variance?

• Activity Number: 103
• Type: Invited
• Date/Time: Monday, August 1, 2011 : 8:30 AM to 10:20 AM
• Sponsor: Section on Survey Research Methods
• Author(s): Brady Thomas West*+ and Kristen Olson
• Companies: Michigan Program in Survey Methodology and University of Nebraska at Lincoln
• Keywords: Interviewer Variance ; Nonresponse Error ; Measurement Error ; Total Survey Error ; Interviewer Effects ; CATI

Abstract

Intra-interviewer correlation can arise when answers from survey respondents interviewed by the same interviewer are more similar to each other than answers from other respondents, decreasing the precision of survey estimates. Estimation of this parameter in practice, however, only uses respondent data. The potential contribution of variance in nonresponse errors between interviewers to this correlation has been largely ignored: responses within interviewers may appear correlated because the interviewers successfully obtain cooperation from different pools of respondents. This study attempts to fill this gap by analyzing a unique survey data set, which includes both true values and reported values for respondents and arises from a CATI sample assignment that approximates interpenetrated assignment of subsamples to interviewers. This data set enables the decomposition of interviewer variance in means of respondent reports into nonresponse error variance and measurement error variance across interviewers. We show that in cases where there is substantial interviewer variance in reported values, the interviewer variance may arise from nonresponse error variance across interviewers.