# confIntV: crossTab, confIntV and cramersV In userfriendlyscience: Quantitative Analysis Made Accessible

## Description

These functions compute the point estimate and confidence interval for Cramer's V. The crossTab function also shows a crosstable.

## Usage

 ```1 2 3 4 5 6 7``` ```crossTab(x, y=NULL, conf.level=.95, digits=2, pValueDigits=3, ...) cramersV(x, y = NULL, digits=2) confIntV(x, y = NULL, conf.level=.95, samples = 500, digits=2, method=c('bootstrap', 'fisher'), storeBootstrappingData = FALSE) ```

## Arguments

 `x` Either a crosstable to analyse, or one of two vectors to use to generate that crosstable. The vector should be a factor, i.e. a categorical variable identified as such by the 'factor' class). `y` If x is a crosstable, y can (and should) be empty. If x is a vector, y must also be a vector. `digits` Minimum number of digits after the decimal point to show in the result. `pValueDigits` Minimum number of digits after the decimal point to show in the Chi Square p value in the result. `conf.level` Level of confidence for the confidence interval. `samples` Number of samples to generate when bootstrapping. `method` Whether to use Fisher's Z or bootstrapping to compute the confidence interval. `storeBootstrappingData` Whether to store (or discard) the data generating during the bootstrapping procedure. `...` Extra arguments to `crossTab` are passed on to `confIntV`.

## Value

The cramersV and confIntV functions return either a point estimate or a confidence interval for Cramer's V, an effect size to describe the association between two categorical variables. The crossTab function is just a wrapper around confIntV.

## Examples

 ```1 2 3 4 5 6``` ```crossTab(infert\$education, infert\$induced, samples=50); ### Get confidence interval for Cramer's V ### Note that by using 'table', and so removing the raw data, inhibits ### bootstrapping, which could otherwise take a while. confIntV(table(infert\$education, infert\$induced)); ```

userfriendlyscience documentation built on May 2, 2019, 1:09 p.m.