Univariate Multiple Imputation for Coarse Employee Income Data

AbstractEmployment income data are coarsened as a result of questionnaire design. In the previous chapter we saw that Statistics South Africa (SSA) ask two employment income questions: an exact income question with a showcard follow-up. In public-use datasets, this results in two income variables: a continuously distributed variable for exact income responses and a categorical variable for bounded income responses with separate categories for nonresponse. It is the task of the researcher to then generate a single income variable that effectively deals with this mixture of data types. Following Heitjan and Rubin (1991), we call a variable with this mixture of data types “coarse data”.