pwr (version 1.2-0)

ES.w2: Effect size calculation in the chi-squared test for association

Description

Compute effect size w for a two-way probability table corresponding to the alternative hypothesis in the chi-squared test of association in two-way contingency tables

Usage

ES.w2(P)

Arguments

P

A two-way probability table (alternative hypothesis)

Value

The corresponding effect size w

References

Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Hillsdale,NJ: Lawrence Erlbaum.

See Also

pwr.chisq.test

Examples

prob<-matrix(c(0.225,0.125,0.125,0.125,0.16,0.16,0.04,0.04),nrow=2,byrow=TRUE)
prob
ES.w2(prob)
pwr.chisq.test(w=ES.w2(prob),df=(2-1)*(4-1),N=200)