Classification by regression

Linear regression can be used for classification too. On the diabetes data, use the NominalToBinary filter to convert the two classes, which are nominal, to the numeric values 0 and 1, and apply linear regression. The result is a predicted number between 0 and 1 for each instance. The addClassification filter is used to add that number as a new attribute; then OneR is applied to choose a good split point on that attribute to predict the original two classes. The procedure is a bit cumbersome, but the result works quite well as a classifier.