pPairedWilcoxon: Paired Wilcoxon

In NSM3: Functions and Datasets to Accompany Hollander, Wolfe, and Chicken - Nonparametric Statistical Methods, Third Edition

Paired Wilcoxon

Description

Function to extend wilcox.test to compute the (exact or Monte Carlo) P-value for paired Wilcoxon data in the presence of ties.

Usage

pPairedWilcoxon(x,y=NA,g=NA,method=NA,n.mc=10000)

Arguments

x	Either a list or a vector containing either all or the first group of data.
y	If x contains the first group of data, y contains the second group of data. Otherwise, not used.
g	If x contains a vector of all of the data, g is a vector of 1's and 2's corresponding to group labels. Otherwise, not used.
method	Either "Exact" or "Monte Carlo", 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.

Details

The data entry is intended to be flexible, so that the two groups of data can be entered in any of three ways. For data a=1,2 and b=3,4 all of the following are equivalent:

pPairedWilcoxon(x=c(1,2),y=c(3,4)) pPairedWilcoxon(x=list(c(1,2),c(3,4))) pPairedWilcoxon(x=c(1,2,3,4),g=c(1,1,2,2))

Value

Returns a list with "NSM3Ch5p" class containing the following components:

m	number of observations in the first data group (X)
n	number of observations in the second data group (Y)
obs.stat	the observed T+ statistic
p.val	upper tail P-value

Note

If there are 0s in the Z values (the difference between X and Y), these will be removed and the calculations will be done based on the smaller sample size, as detailed section 3.1 of Hollander, Wolfe, and Chicken - NSM3.

Author(s)

Grant Schneider

See Also

Also see stats::wilcox.test()

Examples

##Hollander-Wolfe-Chicken Example 3.1 Hamilton Depression Scale Factor IV
x <-c(1.83, .50, 1.62, 2.48, 1.68, 1.88, 1.55, 3.06, 1.30)
y <-c(0.878, .647, .598, 2.05, 1.06, 1.29, 1.06, 3.14, 1.29)

wilcox.test(y,x,paired=TRUE,alternative="less")
pPairedWilcoxon(x,y)

NSM3 documentation built on Nov. 4, 2024, 5:08 p.m.