Tectogrammatical representation: towards a minimal transfer in machine translation

The Prague Dependency Treebank (PDT, as described, e.g., in (Hajič, 1998) or more recently in (Hajič, Pajas and Vidová Hladká, 2001)) is a project of linguistic annotation of approx. 1.5 million word corpus of naturally occurring written Czech on three levels (“layers”) of complexity and depth: morphological, analytical, and tectogrammatical. The aim of the project is to have a reference corpus annotated by using the accumulated findings of the Prague School as much as possible, while simultaneously showing (by experiments, mainly of statistical nature) that such a framework is not only theoretically interesting but possibly also of practical use. In this contribution we want to show that the deepest (tectogrammatical) layer of representation of sentence structure we use, which represents “linguistic meaning” as described in (Sgall, Hajičová and Panevová, 1986) and which also records certain aspects of discourse structure, has certain properties that can be effectively used in machine translation1 for languages of quite different nature at the transfer stage. We believe that such representation not only minimizes the “distance” between languages at this layer, but also delegates individual language phenomena where they belong to whether it is the analysis, transfer or generation processes, regardless of methods used for performing these steps.