ShroutFleissICC1 {superb}

Shrout and Fleiss intra-class correlation functions

Description

The functions ShroutFleissICC1, ShroutFleissICC11 and ShroutFleissICC1k computes the intra-class correlation ICC for a given data frame containing repeated measures in columns cols when the measures are in distinct clusters, identified in column clustercol. See (Shrout and Fleiss 1979).

Usage

ShroutFleissICC1(dta, clustercol, cols)

Arguments

dta

A data frame containing within-subject measures, one participant per line;

clustercol

is the column index where cluster belonging are given;

cols

A vector indicating the columns containing the measures.

Value

ICC the intra-class measure of association.

References

Shrout PE, Fleiss JL (1979). “Intraclass correlations: uses in assessing rater reliability.” Psychological bulletin, 86(2), 420.

Shrout PE, Fleiss JL (1979). “Intraclass correlations: uses in assessing rater reliability.” Psychological bulletin, 86(2), 420.

Examples

# creates a small data frames with 4 subject's scores for 5 measures:
dta <- data.frame(cbind(
        clus <- c(1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3),
        col1 <- c(2, 4, 4, 6, 4, 5, 8, 8, 5, 8, 9, 9)
    ))

ShroutFleissICC1(dta, 1, 2)
# 0.434343434 
ShroutFleissICC11(dta[, 1], dta[,2])
# 0.434343434 

dta2 <- data.frame(cbind(
        clus <- c(1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3),
        col1 <- c(1, 3, 3, 5, 3, 4, 7, 7, 4, 7, 8, 8),
        col1 <- c(2, 4, 4, 6, 4, 5, 8, 8, 5, 8, 9, 9),
        col1 <- c(3, 5, 5, 7, 5, 6, 9, 9, 6, 9, 10, 10)
    ))
 
ShroutFleissICC1(dta2, 1, 2:4)
# 0.7543859649 
ShroutFleissICC1k(dta2[, 1], dta2[,2:4])
# 0.7543859649