Degradation of validity over time: a test and extension of Ackerman's model

The dynamic nature of the predictor-criterion relationship has long been a concern in psychology, especially with regard to the deterioration of validity over time. The authors examine P. L. Ackerman's ( 1987, 1988) hypothesized relationships between different types of predictors and criteria over time using data from previous longitudinal studies. Expert ratings categorized predictors and criteria according to P. L. Ackerman's model. Regression results support the predicted negative curvilinear relationship between cognitive ability and consistent and inconsistent task performance but do not support the predicted relationships between perceptual speed ability and psychomotor ability and consistent and inconsistent task performance. Deterioration of validity was more ubiquitous than has been suggested previously, and the pervasive form of deterioration was cubic with a negative trend. Findings are discussed in the context of catastrophe-chaos models.