icc1a.fn {irrICC}

Intraclass Correlation Coefficient (ICC) under ANOVA Model 1A.

Description

This ICC is associated with the one-factor ANOVA model where each subject could be rated by a different group of raters. This ICC represents a measure of inter-rater reliability among all raters involved in the experiment.

Usage

icc1a.fn(ratings)

Arguments

ratings

This is a data frame containing 3 columns or more. The first column contains subject numbers (there could be duplicates if a subject was assigned multiple ratings) and each of the remaining columns is associated with a particular rater and contains its numeric ratings.

Value

This function returns a list containing the following 9 values: 1. sig2s: the subject variance component. 2. sig2e: the error variance component. 3. icc1a: the ICC/inter-rater reliability coefficient 4. n: the number of subjects. 5. r: the number of raters. 6. max.rep: the maximum number of ratings per subject. 7. min.rep: the minimum number of ratings per subjects. 8. M: the total number of ratings for all subjects and raters. 9. ov.mean: the overall mean rating.

References

Gwet, K.L. (2014): Handbook of Inter-Rater Reliability - 4th ed. - Equation #8.1.3, chapter 8. Advanced Analytics, LLC.

Examples

#iccdata1 is a small dataset that comes with the package. Use it as follows:
library(irrICC)
iccdata1 #see what the iccdata1 dataset looks like
icc1a.fn(iccdata1)
coeff <- icc1a.fn(iccdata1)$icc1a
coeff