Incremental validity of perceptual speed and accuracy over general mental ability

This study extends previous research by examining the incremental validity of a specific aptitude, perceptual speed and accuracy (PS), when it is operationalized as both the number correct (NC) and the number wrong (NW). We test the hypotheses that the NC on the PS test predicts the criterion of task performance and the NW predicts (negatively) rules compliance (RC). Based on the responses of 133 warehouse workers, hierarchical regression analyses supported both hypotheses. After controlling for respondents' demographic characteristics (race, gender, and age) and general mental ability (GMA), the NC on the PS test accounted for incremental validity in prediction of task performance (Delta R = .06, 15% increase), and the NW on the PS test accounted for substantial incremental validity in prediction of (lack of) RC (Delta R = .16, 73% increase). In addition, after controlling for demographic characteristics and both GMA and the specific ability, Conscientiousness accounted for unique validity in prediction of both task performance (Delta R = .07, 15% increase) and RC (Delta R = .06, 16% increase). Practical and theoretical implications for selection practices and models of job performance are discussed.