gk_gamma: Goodman-Kruskal Gamma from a Contingency Table

In easyRaschBayes: Bayesian Rasch Analysis Using 'brms'

Goodman-Kruskal Gamma from a Contingency Table

Description

Computes the Goodman-Kruskal gamma coefficient for an ordinal contingency table. This is an internal helper function.

Usage

gk_gamma(tab)

Arguments

tab	A matrix or table representing a contingency table with rows and columns in ordinal order.

Details

Gamma is defined as (C - D) / (C + D), where C is the number of concordant pairs and D is the number of discordant pairs. Uses cumulative suffix sums for O(nr \times nc) complexity.

Value

A scalar: the gamma coefficient in [-1, 1].

References

Goodman, L. A. & Kruskal, W. H. (1954). Measures of association for cross classifications. Journal of the American Statistical Association, 49(268), 732–764.

easyRaschBayes documentation built on March 28, 2026, 5:07 p.m.