GAD (version 1.1.1)

C.test: Cochran's C test of homogeneity of variances

Description

Performs a Cochran's test of the null hypothesis that the largest variance in several sampled variances are the same.

Usage

C.test(object)

Arguments

object

An object of class lm, containing the specified design.

Value

A list of class htest containing the following components:

statistic

Cochran's C test statistic

p-value

The p-value of the test

alternative

A character string describing the alternative hypothesis

method

The character string Cochran test of homogeneity of variances

data.name

A character string giving the name of the lm object

estimate

Sample estimates of variances

Details

The test statistic is a ratio that relates the largest variance to the sum of the sampled variances.

See Also

gad

Examples

  library(GAD)
  data(rohlf95)
  cg <- as.fixed(rohlf95$cages)
  mq <- as.random(rohlf95$mosquito) 
  model <- lm(wing ~ cg + mq%in%cg, data = rohlf95)
  C.test(model)