Dawai: an R Package for Discriminant Analysis With Additional Information

Abstract

The incorporation of additional information into discriminant rules is receiving in- creasing attention as the rules including this information perform better than the usual rules. In this paper we introduce an R package called dawai, which provides the functions that allow to de ne the rules that take into account this additional information expressed in terms of restrictions on the means, to classify the samples and to evaluate the accuracy of the results. Moreover, in this paper we extend the results and de nitions given in previous papers (Fern andez, Rueda, and Salvador 2006, Conde, Fern andez, Rueda, and Salvador 2012, Conde, Salvador, Rueda, and Fern andez 2013) to the case of unequal co- variances among the populations, and consequently de ne the corresponding restricted quadratic discriminant rules. We also de ne estimators of the accuracy of the rules for the general more than two populations case. The wide range of applications of these pro- cedures is illustrated with two data sets from two di erent elds, i.e., biology and pattern recognition.