| spearnoties {corrperm} | R Documentation |
Computes Spearman correlation and asymptotic p-value with no correction for ties. Only intended for use by cp.test.
spearnoties(x, y, alt = 1)
x |
a vector of x data |
y |
a vector of y data |
alt |
alt specifies the sign of the correlation for the alternative hypothesis: 1 if >0 and -1 if <0 |
a vector consisting of the p-value, the Spearman correlation and the number of pairs used in the calculation.
Douglas M. Potter
x<-rnorm(10)
y<-x+rnorm(10)
spearnoties(x,y)
## The function is currently defined as
function(x,y,alt=1){
#asymptotic spearman test, assumes no ties
sel<-is.na(x-y)==F #elim NAs
d<-rank(x[sel])-rank(y[sel])
n<-length(d)
spear<-1-(6*sum(d^2))/(n^3-n)
p<-1-pnorm(spear*sqrt(n-1))
if(alt==-1)p<-1-p
#return one-sided p-value, statistic, number of comparisons
return(c(p,spear,n))
}