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Improving the precision of classification trees. (English) Zbl 1184.62109
Summary: Besides serving as prediction models, classification trees are useful for finding important predictor variables and identifying interesting subgroups in the data. These functions can be compromised by weak split selection algorithms that have variable selection biases or that fail to search beyond local main effects at each node of the tree. The resulting models may include many irrelevant variables or select too few of the important ones. Either eventuality can lead to erroneous conclusions. Four techniques to improve the precision of the models are proposed and their effectiveness compared with that of other algorithms, including tree ensembles, on real and simulated data sets.
MSC:
62H30Classification and discrimination; cluster analysis (statistics)
05C90Applications of graph theory
65C60Computational problems in statistics