What is a CHAID tree in shogun? Explain with an example.

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This recipe explains what is a CHAID tree explain with an example.
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CHAID Tree

CHAID (Chi-squared Automatic Interaction Detector) algorithm uses the Chi-square test to determine the best next split at each step. CHAID algorithm is a type of decision tree technique.
CHAID accepts nominal or ordinal categorical predictors only. It uses ANOVA F-test for nodes split before it is transformed into ordinal predictors by binning before tree growing If predictors are continuous.

x_train = RealFeatures(feats_train)
x_test = RealFeatures(feats_test)
y_train = MulticlassLabels(labels_train)
y_test = MulticlassLabels(labels_test)

classifier.train(x_train)
predict = classifier.apply_multiclass(x_test)

eval = MulticlassAccuracy()
accuracy = eval.evaluate(predict, y_test)