Overview of Morpho Challenge 2008
This paper gives an overview of Morpho Challenge 2008 competition and results. The goal of the challenge was to evaluate unsupervised algorithms that provide morpheme analyses for words in different languages. For morphologically complex languages, such as Finnish, Turkish and Arabic, morpheme analysis is particularly important for lexical modeling of words in speech recognition, information retrieval and machine translation. The evaluation in Morpho Challenge competitions consisted of both a linguistic and an application oriented performance analysis. In addition to the Finnish, Turkish, German and English evaluations performed in Morpho Challenge 2007, the competition this year had an additional evaluation for Arabic. The results in linguistic evaluation in 2008 show that although the level of precision and recall varies substantially between the tasks in different languages, the best methods seem to deal quite well with all languages involved. The results in information retrieval evaluation indicate that the morpheme analysis has a significant effect in all the tested languages (Finnish, English and German). The best unsupervised and language-independent morpheme analysis methods can also rival the best language-dependent word normalization methods. The Morpho Challenge was part of the EU Network of Excellence PASCAL Challenge Program and organized in collaboration with CLEF.