multcompView (version 0.1-10)

multcompView-package: Summarize multiple paired comparisons

Description

Convert a logical vector or a vector of p-values or a difference or distance matrix into a display identifying the pairs for which the differences were not significantly different or for which the difference exceeded a threshold.

Author

Spencer Graves and Hans-Peter Piepho with help from Sundar Dorai-Raj

Maintainer: Spencer Graves <[e-mail]>

Details

Package:	multcompView
Type:	Package
Version:	0.1-1
Date:	2006-08-06
License:	GPL

Convert a logical vector or a vector of p-values or a difference or distance matrix into either a letter-based display using "multcompLetters" or a graphic roughly like a "T" using "multcompTs" to identify factor levels or similar groupings that are or are not significantly different. Designed for use in conjunction with the output of functions like TukeyHSD, diststats, simint, simtest, csimint, csimtestmultcomp, friedmanmc, kruskalmcpgirmess.

References

Piepho, Hans-Peter (2004) "An Algorithm for a Letter-Based Representation of All-Pairwise Comparisons", Journal of Computational and Graphical Statistics, 13(2)456-466.

John R. Donaghue (2004) "Implementing Shaffer's multiple comparison procedure for a large number of groups", pp. 1-23 in Benjamini, Bretz and Sarkar (eds) Recent Developments in Multiple Comparison Procedures (Institute of Mathematical Statistics Lecture Notes-Monograph Series vol. 47)

Examples

dif3 <- c(FALSE, FALSE, TRUE)
names(dif3) <- c("a-b", "a-c", "b-c")
multcompTs(dif3)
multcompLetters(dif3)

library(MASS)
multcompBoxplot(Postwt~Treat, data=anorexia)