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The correlation of the phi function of the difference score with performance and its relevance to laterality
Abstract:
It is shown that there is a generic correlation between the phi functions of differences in pairs of scores and the averages of pairs of scores. This correlation can be approximated extremely accurately given only the means, variances, and covariance of the two scores in the sample data. Thus, even when difference scores are transformed into their phi equivalents, these are still not independent of performance level.
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