NSM3 (version 1.5)

cKW: Computes a critical value for the Kruskal-Wallis H distribution.

Description

This function computes the critical value for the Kruskal-Wallis H distribution at (or typically in the "Exact" and "Monte Carlo" cases, close to) the given alpha level.

Usage

cKW(alpha,n, method=NA, n.mc=10000)

Arguments

alpha

A numeric value between 0 and 1.

n

A vector of numeric values indicating the size of each of the k data groups.

method

Either "Exact", "Monte Carlo" or "Asymptotic", indicating the desired distribution. When method=NA, "Exact" will be used if the number of permutations is 10,000 or less. Otherwise, "Monte Carlo" will be used.

n.mc

If method="Monte Carlo", the number of Monte Carlo samples used to estimate the distribution. Otherwise, not used.

Value

Returns a list with "NSM3Ch6c" class containing the following components:

n

number of observations in the k data groups

cutoff.U

upper tail cutoff at or below user-specified alpha

true.alpha.U

true alpha level corresponding to cutoff.U (if method="Exact" or "Monte Carlo")

Examples

##Hollander-Wolfe-Chicken Example 6.1 Half-Time of Mucociliary Clearance
#cKW(0.0503,c(5,4,5),"Exact")
cKW(0.7147,c(5,4,5),"Asymptotic")
cKW(0.7147,c(5,4,5),"Monte Carlo",n.mc=20000)