Goodman and Kruskal's lambda

In probability theory and statistics, Goodman and Kruskal's lambda ( λ {\displaystyle \lambda } ) is a measure of proportional reduction in error in cross tabulation analysis. For any sample with a nominal independent variable and dependent variable (or ones that can be treated nominally), it indicates the extent to which the modal categories and frequencies for each value of the independent variable differ from the overall modal category and frequency, i.e., for all values of the independent variable together.

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