Automatic Construction of N-ary Tree Based Taxonomies

Hierarchies are an intuitive and effective organization paradigm for data. Of late there has been considerable research on automatically learning hierarchical organizations of data. In this paper, we explore the problem of learning n-ary tree based hierarchies of categories with no user-defined parameters. We propose a framework that characterizes a "good" taxonomy and also provide an algorithm to find it. This algorithm works completely automatically (with no user input) and is significantly less greedy than existing algorithms in literature. We evaluate our approach on multiple real life datasets from diverse domains, such as text mining, hyper-spectral analysis, written character recognition etc. Our experimental results show that not only are n-ary trees based taxonomies more "natural", but also the output space decompositions induced by these taxonomies for many datasets yield better classification accuracies as opposed to classification on binary tree based taxonomies