Improved AdaBoost.M1 of decision trees with confidence-rated predictions
Zhipeng Xie · 2009
This paper proposes an algorithm to integrate AdaBoost.M1 with the decision trees that output confidence-rated predictions, which is done by transforming decision trees from expert models to specialist models that may abstain when the confidence is less than 1/2. The confidence is used to update the instance weights during the boosting process, and it is also used to determine the vote weights of base classifiers in decision process. This makes the algorithm a dynamic one, in that: (1) for a given test instance, only those whose confidences are higher than 1/2 can vote on the decision making; and (2) the vote weight of each base classifier is dependent on the confidence that the classifier has on the target instance. Experimental results with C4.5 decision tree learner as the base learning algorithm have shown that this algorithm has significantly outperformed both the base algorithm and the AdaBoost.M1 of the C4.5 decision trees with simple predictions.