On testing for stochastic dissociations.

Methods for examining stochastic relationships have been proposed as powerful ways to dissociate different underlying psychological processes, but a number of problems have undermined conclusions based upon these methods. These testing methods and criticisms are reviewed, and the statistical methods for the testing of stochastic dependence are examined using computer simulation. With each of the methods examined, there were difficulties dealing with certain situations that are likely to occur in experiments examining dependence between successive tests. Examination also showed that the sample sizes of some previous studies were insufficient for findings of moderate amounts of dependence, calling some conclusions of stochastic independence into question. The results of the studies presented here suggest that testing for statistical dependence is a statistically perilous technique, but they also suggest several ways in which dedicated users of this form of testing can strengthen its application.