Computes Kendall's coefficient of concordance as an index of interrater reliability of ordinal data. The coefficient could be corrected for ties within raters.
Usage
kendall(ratings, correct = FALSE)
Arguments
ratings
n*m matrix or dataframe, n subjects m raters.
correct
a logical indicating whether the coefficient should be corrected for ties within raters.
Value
A list with class '"irrlist"' containing the following components:
$methoda character string describing the method applied for the computation of interrater reliability.
$subjectsthe number of subjects examined.
$ratersthe number of raters.
$irr.namea character string specifying the name of the coefficient.
$valuecoefficient of interrater reliability.
$stat.namea character string specifying the name and the df of the corresponding chi-squared test.
$statisticthe value of the test statistic.
$p.valuethe p-value for the test.
$errorthe character string of a warning message if ties were found within raters.
Details
Missing data are omitted in a listwise way.
\crKendall's W should be corrected for ties if raters did not use a true ranking order for the subjects.
\crAtest for the significance of Kendall's W is only valid for large samples.