Developing a fast supervised optimum-path forest based on coreset

Optimum-path forest (OPF) is an effective graph-based machine learning that simplifies the pattern recognition problems into the partitioning the corresponding derived graphs of the input datasets. The amounts of the samples in the input datasets and, consequently the size of the node set of their corresponding derived graphs has a major effect on the speed of OPF. In this study a novel version of OPF is introduced which utilizes coreset approach for reducing the scale of the input dataset. From the aspect of the computational geometry, coreset is a small set of points that includes the best representative points of the original point set with regard to a geometric objective function. Our method finds the most informative vertices (samples) by proposing a novel incremental coreset construction algorithm. The experimental results of the proposed method reduces the input data samples, and the execution times of the construction and the classification phases of OPF by 80%, 60%, and 12%, respectively, in contrast to the traditional OPF.