# KrippAlpha: Krippendorff's Alpha Reliability Coefficient In DescTools: Tools for Descriptive Statistics

## Description

Calculate the alpha coefficient of reliability proposed by Krippendorff.

## Usage

 `1` ``` KrippAlpha(x, method=c("nominal", "ordinal", "interval", "ratio")) ```

## Arguments

 `x` classifier x object matrix of classifications or scores `method` data level of x

## Value

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

 `method` a character string describing the method. `subjects` the number of data objects. `raters` the number of raters. `irr.name` a character string specifying the name of the coefficient. `value` value of alpha. `stat.name` here "nil" as there is no test statistic. `statistic` the value of the test statistic (NULL). `p.value` the probability of the test statistic (NULL). `cm` the concordance/discordance matrix used in the calculation of alpha `data.values` a character vector of the unique data values `levx` the unique values of the ratings `nmatchval` the count of matches, used in calculation `data.level` the data level of the ratings ("nominal","ordinal", "interval","ratio")

## Note

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

## Note

This function was previously published as `kripp.alpha()` in the irr package and has been integrated here without logical changes, but with some adaptations in the result structure.

## Author(s)

Jim Lemon <[email protected]>

## References

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

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11``` ```# 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 KrippAlpha(nmm) # now use the same data with the other three methods KrippAlpha(nmm, "ordinal") KrippAlpha(nmm, "interval") KrippAlpha(nmm, "ratio") ```

DescTools documentation built on Sept. 13, 2017, 9:04 a.m.