Preliminary study on automatic recognition of spatial expressions in Polish texts

Abstract

In the paper we cover the problem of spatial expression recognition in text for Polish language. A spatial expression is a text fragment which describes a relative location of two or more physical objects to each other. The first part of the paper treats about a Polish corpus annotated with spatial expressions and annotators agreement. In the second part we analyse the feasibility of spatial expression recognition by overviewing relevant tools and resources for text processing for Polish. Then we present a knowledge-based approach which utilizes the existing tools and resources for Polish, including: a morpho-syntactic tagger, shallow parsers, a dependency parser, a named entity recognizer, a general ontology, a wordnet and a wordnet to ontology mapping. We also present a dedicated set of manually created syntactic and semantic patterns for generating and filtering candidates of spatial expressions. In the last part we discuss the results obtained on the reference corpus with the proposed method and present detailed error analysis.