ParaMor : Minimally Supervised Induction of Paradigm Structure and Morphological Analysis


Paradigms provide an inherent organizational structure to natural language morphology. ParaMor, our minimally supervised morphology induction algorithm, retrusses the word forms of raw text corpora back onto their paradigmatic skeletons; performing on par with state-of-the-art minimally supervised morphology induction algorithms at morphological analysis of English and German. ParaMor consists of two phases. Our algorithm first constructs sets of affixes closely mimicking the paradigms of a language. And with these structures in hand, ParaMor then annotates word forms with morpheme boundaries. To set ParaMor 's few free parameters we analyze a training corpus of Spanish. Without adjusting parameters, we induce the morphological structure of English and German. Adopting the evaluation methodology of Morpho Challenge 2007 ( Kurimo et al., 2007 ), we compare ParaMor 's morphological analyses with Morfessor ( Creutz, 2006 ), a modern minimally supervised morphology induction system. ParaMor consistently achieves competitive F1 measures.