cramersV {lsr}

Cramer's V

Description

Calculate the Cramer's V measure of association

Usage

cramersV(...)

Arguments

...

Arguments to be passed to the chisq.test function.

Details

Calculates the Cramer's V measure of effect size for chi-square tests of association and goodness of fit. The arguments to the cramersV function are all passed straight to the chisq.test function, and should have the same format.

Value

A numeric variable with a single element corresponding to the value of V.

Examples

# Consider an experiment with two conditions, each with 100
# participants. Each participant chooses between one of three
# options. Possible data for this experiment:

condition1 <- c(30, 20, 50)
condition2 <- c(35, 30, 35)
X <- cbind( condition1, condition2 )
rownames(X) <- c( 'choice1', 'choice2', 'choice3' )
print(X)

# To test the null hypothesis that the distribution of choices
# is identical in the two conditions, we would run a chi-square
# test:
chisq.test(X)

# To estimate the effect size we can use Cramer's V:
cramersV( X )  # returns a value of 0.159