Wikipedia-based Compact Hierarchical Semantics with Application to Semantic Relatedness

A proper semantic representation of words and texts underlies many text processing tasks. In this paper, we present a novel representation of semantics which is based on an hierarchical ontology of natural concepts derived from Wikipedia articles and category system. Our method, called Compact Hierarchical Explicit Semantic Analysis (CHESA) generates compact hierarchical representations of unrestricted natural language texts. With comparison to previous methods for semantic representations, CHESA generates very intuitive and comprehensible representations allowing deep semantic reasoning and understanding. CHESA representations are flexible with regards to their level of abstraction and compactness. We present a methodology to compute semantic relatedness using CHESA representations and evaluate CHESA on the task of semantic relatedness assessment of words and texts. Empirical results show that for compact representations, CHESA is superior to the previous state of the art.