ci.agree: Confidence interval for a G-index of agreement

In statpsych: Statistical Methods for Psychologists

Confidence interval for a G-index of agreement

Description

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.

For more details, see Section 3.5 of Bonett (2021, Volume 3)

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

\insertRef

Bonett2022statpsych

\insertRef

Bonett2021statpsych

Examples

ci.agree(.05, 250, 214, 3)

# Should return:
#  Estimate      SE     LL     UL
#     0.784 0.03331 0.7098 0.8414

statpsych documentation built on Jan. 13, 2026, 1:07 a.m.