Evolutionary bagging for ensemble learning

TL;DR

This paper introduces evolutionary bagging, an innovative ensemble learning method that uses evolutionary algorithms to dynamically evolve bag contents, leading to improved performance over traditional bagging and random forests on benchmark datasets.

Contribution

The paper proposes a novel evolutionary bagging approach that evolves data subsets for ensemble learning, enhancing diversity and performance compared to conventional methods.

Findings

Outperforms traditional bagging and random forests on benchmark datasets.

Maintains diversity in bags without sacrificing accuracy.

Enhances ensemble performance through evolutionary evolution of bag contents.

Abstract

Ensemble learning has gained success in machine learning with major advantages over other learning methods. Bagging is a prominent ensemble learning method that creates subgroups of data, known as bags, that are trained by individual machine learning methods such as decision trees. Random forest is a prominent example of bagging with additional features in the learning process. Evolutionary algorithms have been prominent for optimisation problems and also been used for machine learning. Evolutionary algorithms are gradient-free methods that work with a population of candidate solutions that maintain diversity for creating new solutions. In conventional bagged ensemble learning, the bags are created once and the content, in terms of the training examples, are fixed over the learning process. In our paper, we propose evolutionary bagged ensemble learning, where we utilise evolutionary algorithms to evolve the content of the bags in order to iteratively enhance the ensemble by providing diversity in the bags. The results show that our evolutionary ensemble bagging method outperforms conventional ensemble methods (bagging and random forests) for several benchmark datasets under certain constraints. We find that evolutionary bagging can inherently sustain a diverse set of bags without reduction in performance accuracy.