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Confidence interval for a G-index of agreement

Source: R/statpsych3.R
ci.agree.Rd

Computes an adjusted Wald confidence interval for a G-index of agreement between two polychotomous ratings. This function requires the number of objects that were given the same rating by both raters. The G-index corrects for chance agreement. The G-index is a better measure of agreement than Cohen's kappa, and the confidence interval for the G-index used here has better small-sample properties than the confidence interval for Cohen's kappa.

Usage

ci.agree(alpha, n, f, k)

Arguments

alpha

alpha level for 1-alpha confidence

n

sample size

f

number of objects rated in agreement

k

number of rating categories

Value

Returns a 1-row matrix. The columns are:

  • Estimate - maximum likelihood estimate of G-index

  • SE - standard error

  • LL - lower limit of the adjusted Wald confidence interval

  • UL - upper limit of the adjusted Wald confidence interval

References

Bonett DG (2022). “Statistical inference for G-indices of agreement.” Journal of Educational and Behavioral Statistics, 47(4), 438–458. doi:10.3102/10769986221088561 .

Examples

ci.agree(.05, 100, 80, 4)
#>   Estimate         SE        LL        UL
#>  0.7333333 0.05333333 0.6132949 0.8226025

# Should return:
#  Estimate         SE        LL        UL
# 0.7333333 0.05333333 0.6132949 0.8226025