Building Concept Graphs from Monolingual Dictionary Entries

We present the dict{\_}to{\_}4lang tool for processing entries of three monolingual dictionaries of English and mapping definitions to concept graphs following the 4lang principles of semantic representation introduced by (Kornai, 2010). 4lang representations are domain- and language-independent, and make use of only a very limited set of primitives to encode the meaning of all utterances. Our pipeline relies on the Stanford Dependency Parser for syntactic analysis, the dep to 4lang module then builds directed graphs of concepts based on dependency relations between words in each definition. Several issues are handled by construction-specific rules that are applied to the output of dep{\_}to{\_}4lang. Manual evaluation suggests that ca. 75{\%} of graphs built from the Longman Dictionary are either entirely correct or contain only minor errors. dict{\_}to{\_}4lang is available under an MIT license as part of the 4lang library and has been used successfully in measuring Semantic Textual Similarity (Recski and {\'A}cs, 2015). An interactive demo of core 4lang functionalities is available at http://4lang.hlt.bme.hu.