Permutation: Two Sample Exact Permutation Test

In treeperm: Exact and Asymptotic K Sample Permutation Test

Description

This function performs a two sample permutation test of data locations by returning a p value. It is a wrapper function for C level computations. Users are not expected to use this function directly because there is no error checking mechanisms. However, for purpose of performance testing and other demands, this function is visible in this package.

Usage

Permutation(data, factor)
## S3 method for class 'Permutation'
print(x,...)

Arguments

x	The Permutation class to be printed.
data	The set of all data to be permuted
factor	The set of indices, indicating group assignments of values in vector data. This parameter should be in factor type..
...	Reserved for future.

Details

Details about implementations are located in Permutation.c.

Value

Statistics	The observed test statistics for input data. It is the sum of all elements in first group.
Permutations	The total number of permutations can be performed on input groups.
pvalue	The p value of this two sample permutation test.

Note

Although the return value uses a group mean value as test statistics, the actual computation uses the group sum to speed up computation.

Author(s)

Qiao Kang

References

Fisher, R. A. 1925, 'Statistical Methods for Research Workers', Oliver and Boyd, Edinburgh

Examples

value<-c(0,190,0,0,10,0,0,0,0,0,0,110,0,0,52,0,8,0,50,0,0,137,965,110)
label<-as.factor(c(1,1,1,2,2,2,1,1,1,2,2,2,1,1,1,2,2,2,1,1,1,2,2,2))
print(Permutation(value,label))

Example output

Total permutations
[1] 2704156
Observed statistics
[1] 24.33333
P value
[1] 0.3257024

treeperm documentation built on May 2, 2019, 10:23 a.m.