cramer {greybox}

Calculate Cramer's V for categorical variables

Description

Function calculates Cramer's V for two categorical variables based on the table function

Usage

cramer(x, y, use = c("na.or.complete", "complete.obs", "everything",
  "all.obs"), unbiased = TRUE)

Arguments

x

First categorical variable.

y

Second categorical variable.

use

What observations to use. See cor function for details. The only option that is not available here is "pairwise.complete.obs".

unbiased

Determines whether to calculate the biased version of Cramer's V or the one with the small sample correction.

Details

The function calculates Cramer's V and also returns the associated statistics from Chi-Squared test with the null hypothesis of independence of the two variables.

See details in the vignette "Marketing analytics with greybox": vignette("maUsingGreybox","greybox")

Value

The following list of values is returned:

• value - The value of Cramer's V;

• statistic - The value of Chi squared statistic associated with the Cramer's V;

• p.value - The p-value of Chi squared test associated with the Cramer's V;

• df - The number of degrees of freedom from the test.

Author(s)

Ivan Svetunkov, [e-mail]

References

Wicher Bergsma (2013), A bias-correction for Cramér's V and Tschuprow's T. Journal of the Korean Statistical Society, 42, pp. 323-328. doi:10.1016/j.jkss.2012.10.002.

See Also

table, tableplot, spread, mcor, association

Examples

cramer(mtcars$am, mtcars$gear)