Probabilistic Combination of Text Classifiers Using Reliability Indicators: Models and Results

The intuition that different text classifiers behave in qualitatively different ways has long motivated attempts to build a better metaclassifier via some combination of classifiers. We introduce a probabilistic method for combining classifiersthat considers the contextsensitive reliabilities of contributing classifiers. The method harnesses reliability indicators—variables that provide a valuable signal about the performance of classifiers in different situations. We provide background, present procedures for building metaclassi- fiersthat take into consideration both reliability indicators and classifier outputs, and review a set of comparative studies undertaken to evaluate the methodology