rfromPsi {nopaco}

Convertion between Pearson correlation and the non paramtric concordance coefficient

Description

Convertion between Pearson correlation and the non paramtric concordance coefficient

Usage

rfromPsi(psi)

psifromR(r)

Arguments

psi

a (vector of) non paramtric concordance coefficient(s)

r

a (vector of) Pearson correlation coefficient(s)

Details

The convertion is performed following the relationship described by Rothery (1979). 2*cos(pi*(1-psi))-1

Value

A (vector of) corresponding Pearson correlation coefficient(s).

References

Rothery, P. 'A nonparametric measure of intraclass correlation', Biometrika, 66, 3, 629-639 (1979).

See Also

Other concordance functions: coef(), concordance.test(), getPsi()

Examples

#Generate a matrix without concordance
matRandom <- matrix(rnorm(30),10,3)
result<-concordance.test(matRandom)
getPsi(result) #concordance coefficient
result$ci      #95% confidence interval

#Corresonding Pearson correlation
rfromPsi(getPsi(result))
rfromPsi(result$ci)

#Plot the relation between Pearson correlation and the nonparamatric concordance coefficient.
r<-seq(-1,1,0.01)
psi<-psifromR(r)
plot(r,psi,type='l',xlab="Pearson correlation", ylab="nonparametric concordance")