median: Median test. Multiple comparisons

In agricolae: Statistical Procedures for Agricultural Research

Median test. Multiple comparisons

Description

A nonparametric test for several independent samples. The median test is designed to examine whether several samples came from populations having the same median.

Usage

Median.test(y,trt,alpha=0.05,correct=TRUE,simulate.p.value = FALSE, group = TRUE, 
main = NULL,console=TRUE)

Arguments

y	Variable response
trt	Treatments
alpha	error type I
correct	a logical indicating whether to apply continuity correction when computing the test statistic for 2 groups. The correction will not be bigger than the differences themselves. No correction is done if simulate.p.value = TRUE.
simulate.p.value	a logical indicating whether to compute p-values by Monte Carlo simulation
group	TRUE or FALSE
main	Title
console	logical, print output

Details

The data consist of k samples of possibly unequal sample size.
Greater: is the number of values that exceed the median of all data and
LessEqual: is the number less than or equal to the median of all data.

Value

statistics	Statistics of the model
parameters	Design parameters
medians	Statistical summary of the study variable
comparison	Comparison between treatments
groups	Formation of treatment groups

Author(s)

Felipe de Mendiburu

References

Practical Nonparametrics Statistics. W.J. Conover, 1999

See Also

BIB.test, DAU.test, duncan.test, durbin.test, friedman, HSD.test, kruskal, LSD.test, PBIB.test, REGW.test, scheffe.test, SNK.test, waerden.test, waller.test, plot.group

Examples

library(agricolae)
# example 1
data(corn)
out<-with(corn,Median.test(observation,method,console=FALSE))
z<-bar.err(out$medians,variation = "range",ylim=c(0,120),
           space=2,border=4,col=3,density=10,angle=45)
# example 2
out<-with(corn,Median.test(observation,method,console=FALSE,group=FALSE))
print(out$comparison)

agricolae documentation built on Oct. 23, 2023, 1:06 a.m.