19 Feb - Seminari Xavier Carreras

 

El proper divendres 19 de febrer tenim programat un seminari a càrrec de Xavier Carreras a l'aula S208 de l'Edifici Omega del Campus Nord de la UPC.

Aquests són els detalls del seminari: 

Títol A TAG formalism for Parsing and Translation

Ponent Xavier Carreras

Lloc Omega-S208

Dia 19 Febrer 2009

Horari 10:00h - Café

10:15h - Presentació

Abstract Syntactic parsing is the fundamental problem of determining the structure of natural language sentences. It is a challenging task, because syntactic structures of natural languages are recursive, and there is a significant degree of ambiguity in determining how different parts of a sentence combine together syntactically. In any computational model for parsing, the choice of grammar formalism is critical to both the representational power of the model and its computational efficiency. In this talk I will describe a variant of a Tree Adjoining Grammar (TAG) that can use a wide varitey of rich features and, at the same time, has efficient algorithms. I will present two applications of our TAG. The first is a discriminative parser, a generalization of Conditional Random Fields for sequence prediction that extends the framework to syntactic parsing. I will then present a system for Machine Translation that frames the task of translation as a parsing task. This is joint work with Michael Collins and Terry Koo.