Herzing, JessicaJessicaHerzing0000-0002-9010-5927Blom, Annelies G.Annelies G.BlomMeuleman, BartBartMeuleman2024-10-112024-10-112022https://boris-portal.unibe.ch/handle/20.500.12422/87010Despite its importance in terms of survey participation, the literature is sparse on how face-to-face interviewers differentially affect specific groups of sample units. In this paper, we demonstrate how an alternative parametrization of the random components in multilevel models, so-called separate coding, delivers valuable insights into differential interviewer effects for specific groups of sample members. At the example of a face-to-face recruitment interview for a probability-based online panel, we detect small interviewer effects regarding survey participation for non-Internet households, whereas we find sizable interviewer effects for Internet households. Based on the proposed variance decomposition, we derive practical guidance for survey practitioners to address such differential interviewer effects.en300 - Social sciences, sociology & anthropology::370 - Education300 - Social sciences, sociology & anthropology::310 - Statisticsarticle10.48350/17236610.1093/jssam/smac025