MOTE (version 1.0.2)

r.correl: r to Coefficient of Determination (R2) from F

Description

This function displays transformation from r to r2 to calculate the non-central confidence interval for r2 using the F distribution.

Usage

r.correl(r, n, a = 0.05)

Value

Provides correlation coefficient and coefficient of determination with associated confidence intervals and relevant statistics.

r

correlation coefficient

rlow

lower level confidence interval r

rhigh

upper level confidence interval r

R2

coefficient of determination

R2low

lower level confidence interval of R2

R2high

upper level confidence interval of R2

se

standard error

n

sample size

dfm

degrees of freedom of mean

dfe

degrees of freedom of error

t

t-statistic

F

F-statistic

p

p-value

estimate

the r statistic and confidence interval in APA style for markdown printing

estimateR2

the R^2 statistic and confidence interval in APA style for markdown printing

statistic

the t-statistic in APA style for markdown printing

Arguments

r

correlation coefficient

n

sample size

a

significance level

Details

The t-statistic is calculated by first dividing one minus the square root of r squared by degrees of freedom of the error. r is divided by this value.

t = r / sqrt((1 - rsq) / (n - 2))

The F-statistic is the t-statistic squared.

Fvalue = t ^ 2

Learn more on our example page.

Examples

#This example is derived from the mtcars dataset provided in R.

#What is the correlation between miles per gallon and car weight?

cor.test(mtcars$mpg, mtcars$wt)

r.correl(r = -0.8676594, n = 32, a = .05)