A semantic tagger for the Finnish language

This paper reports on the current status and evaluation of a Finnish semantic tagger (hereafter FST), which was developed in the EU-funded Benedict Project. In this project, we have ported the Lancaster English semantic tagger (USAS) to the Finnish language. We have re-used the existing software architecture of USAS, and applied the same semantic field taxonomy developed for English to Finnish. The Finnish lexical resources have been compiled using various corpus-based techniques, and the resulting lexicons have then been manually tagged and used for the FST prototype. At present, the lexicons contain 33,627 single lexical items and 8,912 multi-word expression templates. In the evaluation, we used two sets of test data. The first test data is from the domain of Finnish cooking, which is both sufficiently compact and sufficiently versatile. The second data is from Helsingin Sanomat, the biggest Finnish daily newspaper. As a result, the FST produced a lexical coverage of 94.1% and a precision of 83.03% on the cooking test data and a lexical coverage of 90.7% on the newspaper data. While there is much room for improvement, this is an encouraging result for a prototype tool. The FST will be continually improved by expanding the semantic lexical resources and improving the disambiguation algorithms.