The stability of validity coefficients over time: Ackerman's (1988) model and the general aptitude test battery.

This study examined P. L. Ackerman's (1988) model of skill acquisition within an applied setting. Differences were examined between jobs on the basis of task consistency: changes in performance variability across experience, learning curves, and stability of ability-performance correlations across experience. Results showed the degree of task consistency influenced the shape of learning curves, with jobs composed of primarily consistent tasks improving more rapidly and reaching asymptote sooner. In addition, trends in ability-performance correlations were moderated by the degree of task consistency within ajob. Specifically, forjobs with primarily consistent tasks, general cognitive ability best predicted early performance whereas psychomotor ability best predicted later performance. In contrast, general cognitive ability was the strongest predictor across experience for jobs with primarily inconsistent tasks.