MESS (version 0.5.12)

monte_carlo_chisq_test: Two-sided table test with fixed margins

Description

Monte Carlo test in a two-way contingency table with the total number of observations fixed, row margin fixed, or both margins fixed.

Usage

monte_carlo_chisq_test(x, margin = c("N", "rows", "both"), B = 100000L)

Value

A list of class "htest" giving the simulation results.

Arguments

x

A matrix representing the contingency table.

margin

A string that determines which margin is fixed: Either "N" for the total number of observations (the default), "rows" for fixed row sums, and "both" for simultaneously fixed row and column sums.

B

The number of simulations used to compute the p-value.

Author

Claus Ekstrom <[e-mail]>

Details

Simulation is done by random sampling from the set of all tables with given marginal(s), and works only if the relevant marginal(s) are strictly positive. Continuity correction is never used, and the statistic is quoted without it.

Examples

m <- matrix(c(12, 4, 8, 6), 2)
chisq.test(m)
chisq.test(m, correct=FALSE)
monte_carlo_chisq_test(m)

fisher.test(m)
monte_carlo_chisq_test(m, margin="both")

m2 <- matrix(c(9, 3, 3, 7), 2)
monte_carlo_chisq_test(m, margin="N")
monte_carlo_chisq_test(m, margin="both")