Guide to calculating, interpreting and using effect size

By making some additional assumptions, one can readily convert d into r in general, using the equation r2 = d2 / (4+d2) (see Cohen, 1969, pp20-22 for other formulae and conversion table). Rosenthal and Rubin (1982) take advantage of an interesting property of r to suggest a further interpretation, which they call the binomial effect size ... ................
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