Pfaffel Andreas, Kollmayer Marlene, Schober Barbara, Spiel Christiane
Department of Applied Psychology: Work, Education, Economy, Faculty of Psychology, University of Vienna, Vienna, Austria.
PLoS One. 2016 Mar 28;11(3):e0152330. doi: 10.1371/journal.pone.0152330. eCollection 2016.
A recurring methodological problem in the evaluation of the predictive validity of selection methods is that the values of the criterion variable are available for selected applicants only. This so-called range restriction problem causes biased population estimates. Correction methods for direct and indirect range restriction scenarios have widely studied for continuous criterion variables but not for dichotomous ones. The few existing approaches are inapplicable because they do not consider the unknown base rate of success. Hence, there is a lack of scientific research on suitable correction methods and the systematic analysis of their accuracies in the cases of a naturally or artificially dichotomous criterion. We aim to overcome this deficiency by viewing the range restriction problem as a missing data mechanism. We used multiple imputation by chained equations to generate complete criterion data before estimating the predictive validity and the base rate of success. Monte Carlo simulations were conducted to investigate the accuracy of the proposed correction in dependence of selection ratio, predictive validity, and base rate of success in an experimental design. In addition, we compared our proposed missing data approach with Thorndike's well-known correction formulas that have only been used in the case of continuous criterion variables so far. The results show that the missing data approach is more accurate in estimating the predictive validity than Thorndike's correction formulas. The accuracy of our proposed correction increases as the selection ratio and the correlation between predictor and criterion increase. Furthermore, the missing data approach provides a valid estimate of the unknown base rate of success. On the basis of our findings, we argue for the use of multiple imputation by chained equations in the evaluation of the predictive validity of selection methods when the criterion is dichotomous.
在评估选拔方法的预测效度时,一个反复出现的方法学问题是,只有被选中的申请者才有标准变量的值。这种所谓的范围限制问题会导致总体估计出现偏差。对于连续型标准变量,直接和间接范围限制情形的校正方法已经得到了广泛研究,但对于二分变量则不然。现有的少数方法不适用,因为它们没有考虑未知的成功基础率。因此,对于自然或人为二分标准情形下合适的校正方法及其准确性的系统分析缺乏科学研究。我们旨在通过将范围限制问题视为一种缺失数据机制来克服这一缺陷。在估计预测效度和成功基础率之前,我们使用链式方程多重填补法生成完整的标准数据。在一个实验设计中,进行了蒙特卡洛模拟,以研究根据选择率、预测效度和成功基础率提出的校正方法的准确性。此外,我们将我们提出的缺失数据方法与桑代克著名的校正公式进行了比较,到目前为止,这些公式仅用于连续型标准变量的情况。结果表明,缺失数据方法在估计预测效度方面比桑代克的校正公式更准确。我们提出的校正方法的准确性随着选择率以及预测变量与标准变量之间的相关性增加而提高。此外,缺失数据方法提供了对未知成功基础率的有效估计。基于我们的研究结果,我们主张在标准为二分变量时,使用链式方程多重填补法来评估选拔方法的预测效度。