get.ICC: Intra-class Correlations
In multicon: Multivariate Constructs

Description Usage Arguments Details Value Note Author(s) References See Also Examples

Calculates the 6 intra-class correlations for the columns in the matrix or data.frame x, where the columns are typically raters or items, following Shrout and Fleiss (1979).

1	get.ICC(x)

`x`	A matrix or data.frame on which to calculate ICCs of the columns.

This function is the workhorse function for item.ICC and Profile.ICC. It computes the intra-class correlations for a single item and for the composite of the items in the data.frame or matrix x. Of note, the results should be intepreted with extreme caution if values in x are missing. If possible, the best choice is to remove missing values from x first.

A matrix containing the values for the six possible intra-class correlations described by Shrout and Fleiss (1979).

This function is the workhorse function for item.ICC and Profile.ICC. It is rarely used as a stand alone function.

Ryne A. Sherman

Shrout, P. E. & Fleiss, J. L. (1979). Intraclass correlations: Uses in assessing rater reliability. Psychological Bulletin, 86, 420-428

item.ICC Profile.ICC

1 2	y <- matrix(rnorm(200), ncol=2) get.ICC(y)

Loading required package: psych
Loading required package: abind
Loading required package: foreach
          ICC1     ICC1k      ICC2     ICC2k      ICC3     ICC3k
[1,] 0.1108492 0.1995755 0.1119431 0.2013468 0.1122192 0.2017934