# How to calculate confidence intervals of correlations with R

[This article was first published on

Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.

**Jeromy Anglim's Blog: Psychology and Statistics**, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.

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.

### Formulas

- Online Statsbookhas formulas for calculating the confidence interval of a correlation coefficient.

### R

Download and Install R (R Home Page; Windows Installation)

Start R and run the following commands, updating the

`CIr`

command as required:

install.packages("psychometric") # install package with function library(psychometric) # load package with function # The following command calculates lower and upper # 95% confidence intervals (level) # assuming sample size (n) is 100 # and the obtained correlation (r) is 0.90 CIr(r=.9, n = 100, level = .95)

To

**leave a comment**for the author, please follow the link and comment on their blog:**Jeromy Anglim's Blog: Psychology and Statistics**.R-bloggers.com offers

**daily e-mail updates**about R news and tutorials about learning R and many other topics. Click here if you're looking to post or find an R/data-science job.

Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.