kendall: Kendall's coefficient of concordance W

In irr: Various Coefficients of Interrater Reliability and Agreement

Description

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.

Details

Missing data are omitted in a listwise way.
Kendall's W should be corrected for ties if raters did not use a true ranking order for the subjects.
A test for the significance of Kendall's W is only valid for large samples.

Value

A list with class '"irrlist"' containing the following components:

$method	a character string describing the method applied for the computation of interrater reliability.
$subjects	the number of subjects examined.
$raters	the number of raters.
$irr.name	a character string specifying the name of the coefficient.
$value	coefficient of interrater reliability.
$stat.name	a character string specifying the name and the df of the corresponding chi-squared test.
$statistic	the value of the test statistic.
$p.value	the p-value for the test.
$error	the character string of a warning message if ties were found within raters.

Author(s)

Matthias Gamer

References

Kendall, M.G. (1948). Rank correlation methods. London: Griffin.

See Also

cor, meanrho

Examples

data(anxiety)
kendall(anxiety, TRUE)

Example output

Loading required package: lpSolve
 Kendall's coefficient of concordance Wt

 Subjects = 20 
   Raters = 3 
       Wt = 0.54 

Chisq(19) = 30.8 
  p-value = 0.0429 

irr documentation built on May 2, 2019, 8:50 a.m.