cochran.qtest: Cochran's Q test

In RVAideMemoire: Testing and Plotting Procedures for Biostatistics

Cochran's Q test

Description

Performs the Cochran's Q test for unreplicated randomized block design experiments with a binary response variable and paired data. If the p-value of the test is significant, the function performs pairwise comparisons by using the Wilcoxon sign test.

Usage

cochran.qtest(formula, data, alpha = 0.05, p.method = "fdr")

Arguments

formula	a formula of the form a ~ b | c, where a, b and c give the data values and corresponding groups and blocks, respectively. a can be a numeric vector or a factor, with only two possible values.
data	an optional data frame containing the variables in the formula formula. By default the variables are taken from environment(formula).
alpha	significance level to compute pairwise comparisons.
p.method	method for p-values correction. See help of p.adjust.

Details

If the response is a 0/1 variable, the probability of the '1' group is tested. In any other cases, the response is transformed into a factor and the probability of the second level is tested.

Value

method.test	a character string giving the name of the global test computed.
data.name	a character string giving the name(s) of the data.
alternative	a character string describing the alternative hypothesis.
estimate	the estimated probabilities.
null.value	the value of the difference in probabilities under the null hypothesis, always 0.
statistic	test statistics (Pearson's Chi-squared test only).
parameter	test degrees of freedom (Pearson's Chi-squared test only).
p.value	p-value of the global test.
alpha	significance level.
p.adjust.method	method for p-values correction.
p.value.multcomp	data frame of pairwise comparisons result.
method.multcomp	a character string giving the name of the test computed for pairwise comparisons.

Author(s)

Maxime HERVE <[e-mail]>

Examples

response <- c(0,1,1,0,0,1,0,1,1,1,1,1,0,0,1,1,0,1,0,1,1,0,0,1,0,1,1,0,0,1)
fact <- gl(3,1,30,labels=LETTERS[1:3])
block <- gl(10,3,labels=letters[1:10])
cochran.qtest(response~fact|block)

RVAideMemoire documentation built on Nov. 6, 2023, 5:07 p.m.