Using Singular Value Decomposition toCompute Answer Similarity in a Language Independent Approach to Question Answering

摘要

In this paper we report on new developments in our data-driven, non-linguistic, language-independent approach to Question Answering (QA). In particular, we describe a new implementation of the filter-model, which is used for answer typing, where we employ the Singular Value Decomposition (SVD) in a variation on the popular Latent Semantic Analysis technique. We also describe refinements to the open-source SVD code that we used which enable us to perform the SVD on arbitrarily large matrices. Finally, we discuss results from the TREC 2005 and TREC 2006 QA evaluations in which we applied these new techniques, and compare them to results achieved with our previous filter-model approach. In particular, we show that our new filter-model using the SVD achieves an average absolute gain of around 8% and an average relative gain of nearly 59% over our previous approach for top one answer accuracy. By using both approaches in combination we are able to increase the absolute gain to approximately 10% and the relative gain to 67%.