Chi2: feature selection and discretization of numeric attributes

Abstract

Discretization can turn numeric attributes into discrete ones. Feature selection can eliminate some irrelevant attributes. This paper describes Chi2, a simple and general algorithm that uses the X2 statistic to discretize numeric attributes repeatedly until some inconsistencies are found in the data, and achieves feature selection via discretization. The empirical results demonstrate that Chi2 is effective in feature selection and discretization of numeric and ordinal attributes.