Joint Annotation of Morphology and Syntax in Dependency Treebanks

Abstract

In this paper, we compare different ways to annotate both syntactic and morphological relations in a dependency treebank and we propose new formats we call mSUD and mUD, compatible with the Universal Dependencies (UD) schema for syntactic treebanks. We emphasize mSUD rather than mUD, the former being based on distributional criteria for the choice of the head of any combination, which allow us to clearly encode the internal structure of a word, that is, the derivational path. We investigate different problems posed by a morph-based annotation, concerning tokenization, choice of the head of a morph combination, relations between morphs, additional features needed, such as the token type differentiating roots and derivational and inflectional affixes. We show how our annotation schema can be applied to different languages from polysynthetic languages such as Yupik to isolating languages such as Chinese.