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A measure of effect size for r x c contingency tables
Kenneth J Berry1, Janis E Johnston, Paul W Mielke
1Department of Sociology, Colorado State University, Fort Collins, CO 80523-1784, USA. berry@lamar.colostate.edu
Abstract:
Goodman and Kruskal's tau measure of categorical association is advanced as a replacement for conventional measures of effect size for r x c contingency tables. Goodman and Kruskal's tau is an asymmetric measure of categorical association which is based entirely on the observed data and possesses a clear interpretation in terms of proportional reduction in error. Comparisons with conventional measures of effect size based on chi-squared such as Pearson's phi2, Tschuprow's T2, and Cramer's V2 demonstrate the advantages of employing tau as a measure of effect size.
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