This post sets out how to calculate confidence intervals for correlations using R. Because I often get this question from people unfamiliar with R, it assumes no prior knowledge of R.
- Online Statsbookhas formulas for calculating the confidence interval of a correlation coefficient.
Start R and run the following commands, updating the
CIrcommand as required:
install.packages("psychometric") # install package with function<br />library(psychometric) # load package with function<br /><br /># The following command calculates lower and upper <br /># 95% confidence intervals (level)<br /># assuming sample size (n) is 100<br /># and the obtained correlation (r) is 0.90<br />CIr(r=.9, n = 100, level = .95)<br />