DTK (version 3.5)

DTK.test: Dunnett's Modified Tukey-Kramer Pairwise Multiple Comparison Test

Description

Conducts a pairwise multiple comparison test (using the C procedure) for mean differences with unequal sample sizes and no assumption of equal population variances.

Usage

DTK.test(x = "data vector", f = "factor vector", a = "alpha level")

Arguments

x

Numeric data vector.

f

Factored level vector.

a

Alpha, significance level. DEFAULT=0.05

Value

[[1]]

"a" or the alpha significance level

[[2]]

Matrix containing the pair-waise comparisons as row names and the pairwise mean differences and lower and upper confidence interval values in columns, respectively

Details

Input data as vectors.

References

Dunnett,C.W. (1980) Pairwise Multiple Comparisons in the Unequal Variance Case. Journal of the American Statistical Association. 75 (372): 796-800.

See Also

DTK.plot, gl.unequal, TK.test, TukeyHSD, qtukey

Examples

x=c(rnorm(25,5,2),rnorm(30,5,5),rnorm(35,15,5))
f<-gl.unequal(n=3,k=c(25,30,35))
DTK.result<-DTK.test(x=x,f=f,a=0.05)
DTK.result
DTK.plot(DTK.result)