R: Effect size calculation in the chi-squared test for...

ES.w2 {pwr} | R Documentation

## 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

### Author(s)

Stephane CHAMPELY

### 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)

[Package pwr version 1.2-2 Index]