Generalized Gini Correlation and its Application in Data-Mining

An asymmetric correlation measure commonly used in social economics, called the Gini correlation, is defined between a numerical response and a rank. We generalize the definition of this correlation so that it can be applied to data mining. The new definition, called the generalized Gini correlation, is found to include special cases that are equivalent to common evaluation measures used in data mining, for example, the LIFT measures for a binary response and the expected profit measure for a monetary response. We consider estimation and inference regarding this generalized Gini correlation. The asymptotic distribution of the estimated correlation is derived with the help of some empirical process theory. We consider several ways of constructing confidence intervals and demonstrate their performance numerically. Our paper is interdisciplinary and makes contributions to both the Gini literature and the literature of statistical inference of performance measures in data mining.