chisq.indep: Power calculation for chi-square test of independence

In powertools: Power and Sample Size Tools

Power calculation for chi-square test of independence

Description

Performs power and sample size calculations for a chi-square test of independence. The user inputs a matrix of cell probabilities for a two-way table. The function computes the power (or required total sample size) for a test of no association between the two factors.

Usage

chisq.indep(pmatrix = NULL, N = NULL, alpha = 0.05, power = NULL, v = FALSE)

Arguments

pmatrix	The two-way probability table under the alternative hypothesis. The probabilities must sum to 1.
N	The total number of observations.
alpha	The significance level (type 1 error rate); defaults to 0.05.
power	The specified level of power.
v	Either TRUE for verbose output or FALSE (default) to output computed argument only.

Value

A list of the arguments (including the computed one).

Examples

chisq.indep(pmatrix = matrix(c(0.050, 0.350, 0.100, 0.075, 0.250, 0.175),
nrow = 2, byrow = TRUE), N = 230)
chisq.indep(pmatrix = matrix(c(0.3, 0.2, 0.4, 0.1), nrow = 2, byrow = TRUE), N = 200)

powertools documentation built on April 4, 2025, 5:02 a.m.