This equation clearly has the same form as the (blue) equation expressing the mutual information between the feature set and the category variable; the difference is that the sum formula_72 in the category utility equation runs over independent binary variables formula_2, whereas the sum formula_74 in the mutual information runs over "values" of the single formula_44-ary variable formula_43. The two measures are actually equivalent then "only" when the features formula_77, are "independent" (and assuming that terms in the sum corresponding to formula_78 are also added).