kripp.alpha {concord}R Documentation

calculate Krippendorff's alpha reliability coefficient

Description

calculates the alpha coefficient of reliability proposed by Krippendorff

Usage

 kripp.alpha(x, method="nominal")

Arguments

x classifier by object matrix of classifications
method data level of x

Value

statistic value of alpha
coincidence.matrix the concordance/discordance matrix used in the calculation of alpha
data.values a character vector of the unique data values
nmatchval the count of matches, used in calculation

Note

Krippendorff's alpha coefficient is particularly useful where the level of measurement of classification data is higher than nominal or ordinal.

Author(s)

Jim Lemon

References

Krippendorff, K. (1980) Content analysis: An introduction to its methodology. Beverly Hills, CA: Sage.

See Also

coincidence.matrix

Examples

 # the "C" data from Krippendorff
 nmm<-matrix(c(1,1,NA,1,2,2,3,2,3,3,3,3,3,3,3,3,2,2,2,2,1,2,3,4,4,4,4,4,
 1,1,2,1,2,2,2,2,NA,5,5,5,NA,NA,1,1,NA,NA,3,NA),nrow=4)
 # first assume the default nominal classification
 kripp.alpha(nmm)
 # now use the same data with the other three methods
 kripp.alpha(nmm,"ordinal")
 kripp.alpha(nmm,"interval")
 kripp.alpha(nmm,"ratio") 

[Package concord version 1.4-9 Index]