The coincidence matrix counts every ordered pair of values within a unit, weighted by 1/(m_u - 1), so units coded by different numbers of coders are handled without imputation. The difference function is what encodes the level of measurement.
Details
Formula: alpha = 1 - D_o / D_e with D_o = sum o_ck delta^2 / n and D_e = sum n_c n_k delta^2 / (n (n - 1)).
References
Krippendorff (2004), Content Analysis: An Introduction to Its Methodology, 2nd ed., Sage, ch. 11.
Examples
V <- c(1, 2, 3, 4, 5, 6, 7, 8)
Krpalp(V)
#> $estimate
#> [1] -1.110223e-15
#>
#> $alpha
#> [1] -1.110223e-15
#>
#> $D_o
#> [1] 1
#>
#> $D_e
#> [1] 1
#>
#> $n_pairable
#> [1] 8
#>
#> $n_units
#> [1] 1
#>
#> $method
#> [1] "alpha = 1 - D_o/D_e on the coincidence matrix, Krippendorff (2004) ch. 11"
#>
#> attr(,"class")
#> [1] "morie_rich_result" "list"
