# [R] How to calculate average correlation coefficient of a correlation matrix ?

Chuck Cleland ccleland at optonline.net
Tue Oct 13 16:38:38 CEST 2009

```On 10/13/2009 10:13 AM, Amit Kumar wrote:
> Hi! All,
> I have large correlation matrix Cor. I wish to calculate average
> correlation coefficient for this matrix.
> Is there any function in R to do this?

cormat <- cor(iris[,1:4])

corlowtri <- cormat[lower.tri(cormat)]

corlowtri
[1] -0.1175698  0.8717538  0.8179411 -0.4284401 -0.3661259  0.9628654

mean(corlowtri)
[1] 0.2900708

mean(abs(corlowtri))
[1] 0.594116

avgcor <- function(x){mean(abs(x[lower.tri(x)]))}

avgcor(cor(iris[,1:4]))
[1] 0.594116

> Amit
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> and provide commented, minimal, self-contained, reproducible code.

--
Chuck Cleland, Ph.D.
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```