Explainable Models via Compression of Tree Ensembles
This addresses the interpretability issue for users of probabilistic logic models, though it is incremental as it builds on existing ensemble methods.
The paper tackles the problem of interpretability loss in ensemble models of relational decision trees by compressing them into a single explainable model, resulting in an effective method called CoTE that produces a small decision list as shown in experimental evaluations on benchmark relational data sets.
Ensemble models (bagging and gradient-boosting) of relational decision trees have proved to be one of the most effective learning methods in the area of probabilistic logic models (PLMs). While effective, they lose one of the most important aspect of PLMs -- interpretability. In this paper we consider the problem of compressing a large set of learned trees into a single explainable model. To this effect, we propose CoTE -- Compression of Tree Ensembles -- that produces a single small decision list as a compressed representation. CoTE first converts the trees to decision lists and then performs the combination and compression with the aid of the original training set. An experimental evaluation demonstrates the effectiveness of CoTE in several benchmark relational data sets.