The performance of five simple multiple imputation methods for dealing with missing data were compared. In addition, random imputation and multivariate normal imputation were used as lower and upper benchmark, respectively. Test data were simulated and item scores were deleted such that they were either missing completely at random, missing at…

Classical methods for detecting outliers deal with continuous variables. These methods are not readily applicable to categorical data, such as incorrect/correct scores (0/1) and ordered rating scale scores (e.g., 0,..., 4) typical of multi-item tests and questionnaires. This study proposes two definitions of outlier scores suited for categorical…

Objective criteria for evaluating the Eysenck Personality Inventory's internal structure are discussed. An approach based on targeted rotations and the test's scoring key is proposed as a means of providing common criteria. Data from earlier structure and test results for 195 undergraduates support the utility of 3 criteria developed. (SLD)