Wuyts, Celine, and Geert Loosveldt. “Observing Interviewer Performance in Slices or by Traces: A Comparison of Methods to Predict Interviewers’ Individual Contributions to Interviewer Variance”. Survey Research Methods, vol. 16, no. 2, Aug. 2022, pp. 147-63, doi:10.18148/srm/2022.v16i2.7672.