ci.ICC2a.nointer function

Confidence Interval of ICCa(2,1) under Model 2 without subject-rater interaction.

This function computes the confidence interval associated with the Intraclass Correlation Coefficient (ICC) formulated as a measure of Intra-Rater Reliability under the random factorial ANOVA model (Model 2) without subject-rater interaction. This function produces the lower and upper confidence bounds.

ci.ICC2a.nointer(dfra, conflev = 0.95)

Arguments

• dfra: 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.
• conflev: This is the optional confidence level associated with the confidence interval. If not specified, the default value will be 0.95, which is the most commonly-used valuee in the literature.

Returns

This function returns a vector containing the lower confidence (lcb) and the upper confidence bound (ucb).

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
ci.ICC2a.nointer(iccdata1)

References

Gwet, K.L. (2014): Handbook of Inter-Rater Reliability - 4th ed. chapter 9, section 9.5.1, equations 9.5.11 and 9.5.12,page 259. Advanced Analytics, LLC.