weight.matrix {nparcomp}R Documentation

Nonparametric relative contrast effects: the weight matrix

Description

The function weight.matrix computes the weight matrix for a given contrast with which the estimator for the relative contrast effect is comupted

Usage

weight.matrix(n, type = c("Tukey", "AVE", "Dunnett", "Sequen", "Changepoint", "Marcus", "McDermott", "Williams"), base = 1)

Arguments

n n vector of sample sizes
type type Character string defining the type of contrast. It should be one of "Tukey", "Dunnett", "Sequen", "Williams", "Changepoint", "AVE", "McDermott", "Marcus"
base base Number of the basline values in Dunnett Comparisons. By default it is base = 1

Details

The function needs the R-function 'contrMat' from the R-package 'multcomp'.

Value

The function returns the weight matrix which can be used to compute the estimator of the relative contrast effect

Note

For the analysis, the R-package 'multcomp' is required.

Author(s)

Frank Konietschke

References

Konietschke, F., Brunner, E., Hothorn, L.A. (2008). Nonparametric Relative Contrast Effects: Asymptotic Theory and Small Sample Approximations, Konietschke, F., Brunner, E., Hothorn, L.A. (2008). Simultaneous Confidence Intervals for Relative Effects in Dunnett Comparsisons.

See Also

contrMat in package multcomp for contrast matrices

Examples

n<-c(10,20,30,40)
weight.matrix(n, "Tukey") # result: identity matrix by construction
weight.matrix(n, "Dunnett", base = 3) # Weight matrix for Dunnett comparison - 3rd group is baseline
weight.matrix(n, "Changepoint") # weight matrix for relative changepoint  effect

# For comparison, see the contrasts matrices 
# available in the multcomp package:

library(multcomp)
n<-c(10,10,20,30,40)
contrMat(n, "Changepoint") # Contrast matrix for Changepoint comparisons


[Package nparcomp version 1.0-0 Index]