Assessment of response pattern aberrancy in Eysenck Personality Inventory

The presented study deals with two well standardized and relatively powerful indices based on Item Response Theory – z₃ and F₂ – which we used for detecting aberrant responding in the field of personality assessment. The indices were used on the Neuroticism and Extraversion scales from Eysenck Personality Inventory. The research sample consisted of 427 subjects. Both indices were computed for the whole sample and it was found that they yielded similar results. We selected subjects with the lowest z₃ index (highest aberrancy) values and further analyzed their response patterns. Our results suggest that in some cases the inconsistency was caused by faulty or careless responding, but in other cases by discrepancy between the subject's test behavior (item responding) and the theoretical construct being measured.