PASCAL - Pattern Analysis, Statistical Modelling and Computational Learning

Dependency-based answer validation for German
Svitlana Babych, Alexander Henn, Jan Pawellek and Sebastian Pado
In: CLEF 2011, Amsterdam, The Netherlands(2011).


This article describes the Heidelberg contribution to the CLEF 2011 QA4MRE task for German. We focus on the objective of not using any external resources, building a system that represents questions, answers and texts as formulae in propositional logic derived from dependency structure. Background knowledge is extracted from the background corpora using several knowledge extraction strategies. We answer questions by attempting to infer answers from the test documents complemented by background knowledge, with a distance measure as fall-back. The main challenge is to specify the translation from dependency structure into a logical representation. For this step, we suggest dierent rule sets and evaluate various conguration parameters that tune accuracy and coverage. All of runs exceed a random baseline, but show dierent coverage/accuracy profiles (accuracy up to 44%, coverage up to 65%).

EPrint Type:Conference or Workshop Item (Paper)
Project Keyword:Project Keyword UNSPECIFIED
Subjects:Natural Language Processing
ID Code:8485
Deposited By:Sebastian Pado
Deposited On:16 February 2012