pspearman: Distribution function of Spearman's rho
Description
This function provides three types of approximations of the distribution
function of Spearman's rho. Besides the two approximations
used in cor.test(,method="spearman"), which are AS89 and the t-distribution,
this function allows to use precomputed null distribution for n <= 22.
See spearman.test for the details of the algorithm used to compute this
null distribution.
Usage
pspearman(s, n, lower.tail = TRUE,
approximation = c("exact", "AS89", "t-distribution"))
Arguments
s
The observed value of S statistics sum((rank(x) - rank(y))^2).
n
The number of observations.
lower.tail
If TRUE (the default), the probability of S <= s
is computed. If FALSE, the probability of S >= s is computed.
approximation
Selection of the method of approximation of the distribution
function.
Value
Depending on lower.tail, either the probability of S <= s
or of S >= s is computed, where S is the statistics
sum((rank(x) - rank(y))^2).