Self-adaptive heterogeneous random forest
2014 IEEE/ACS 11th International Conference on Computer Systems and Applications (AICCSA)
Random Forest RF is an ensemble learning approach that utilises a number of classifiers to contribute though voting to predicting the class label of any unlabelled instances. Parameters such as the size of the forest N and the number of features used at each split M , has significant impact on the performance of the RF especially on instances with very large number of attributes. In a previous work Genetic Algorithms has been used to dynamically optimize the size of RF. This study extends this
... enetic algorithm approach to further enhance the accuracy of Random Forests by building the forest out of heterogeneous decision trees, heterogeneous here means trees with different M values. The approach is termed as Heterogeneous Genetic Algorithm based Random Forests (HGARF). As Random Forests generates a typical large number of decision trees with randomisation over the feature space when splitting at each node for all the trees, this has motivated the development of a genetic algorithm based optimisation. Typically, HGARF accepts as an input a forest −→ RF of N trees, the initial population is randomly generated from −→ RF as a number of smaller random forests − → rfi where each one has a number ni ≤ N of trees. This population of forests is then evolved through a number of generations using genetic algorithms. Our extensive experimental study has proved that Random Forests performance could be boosted using the genetic algorithm approach.