Estimation of Interviewer Effects for Categorical Items in a Random Digit Dial Telephone Survey

Abstract

Abstract The loss of precision in estimates of means due to variability among interviewers can be substantial for some questionnaire items and survey designs. The most commonly used methods for estimating the magnitude of this loss are inappropriate for binary items in complex surveys. This article shows how parameters from a model for variance components in binary variables (Anderson and Aitkin 1985) are related to the increased variance of population estimates. It is suggested that one of these parameters, a measure of correlation between interviewer observations on a latent variable, may be more appropriate than the intrainterviewer correlation p for measuring the magnitude of interviewer effects. This is because it is unaffected by the level of the attribute in the population, which is not true of p. Interviewer effects for a household respondent's recorded labor-force status in a random digit dial telephone survey are examined using the new model and estimation process. Small but positive effects are...