[R-meta] effect size question

[H W]

Hi all, I have a question regarding Cohen's *w*.

A textbook I have been using describes the effect size Cohen's *w* =
chi-square/ (N(J-1)) for a goodness of fit test. N is the total sample size
and J is the number of categories.

However, other material shows the formula for Cohen's *w* was the square
root of (chi-square/n).

These two seem to be different, but I don't have enough familiarity to
immediately tell which one is correct, or if both are correct under certain
circumstances. Thank you for your help.

Best regards,
Huang

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