fisherz {psych} R Documentation

Fisher r to z and z to r and confidence intervals

Description

Convert a correlation to a z score or z to r using the Fisher transformation or find the confidence intervals for a specified correlation. r2d converts a correlation to an effect size (Cohen's d) and d2r converts a d into an r.

Usage

```fisherz(rho)
fisherz2r(z)
r.con(rho,n,p=.95,twotailed=TRUE)
r2t(rho,n)
r2d(rho)
d2r(d)
```

Arguments

 `rho` a Pearson r `z` A Fisher z `n` Sample size for confidence intervals `p` Confidence interval `twotailed` Treat p as twotailed p `d` an effect size (Cohen's d)

Value

z value corresponding to r (fisherz) \ r corresponding to z (fisherz2r) \ lower and upper p confidence intervals (r.con) \ t with n-2 df (r2t) r corresponding to effect size d or d corresponding to r.

Author(s)

Maintainer: William Revelle revelle@northwestern.edu

Examples

```
cors <- seq(-.9,.9,.1)
zs <- fisherz(cors)
rs <- fisherz2r(zs)
round(zs,2)
n <- 30
r <- seq(0,.9,.1)
rc <- matrix(r.con(r,n),ncol=2)
t <- r*sqrt(n-2)/sqrt(1-r^2)
p <- (1-pt(t,n-2))/2
r.rc <- data.frame(r=r,z=fisherz(r),lower=rc[,1],upper=rc[,2],t=t,p=p)
round(r.rc,2)

```

[Package psych version 1.4.5 Index]
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