A data driven approach to query expansion in question answering
Leon Derczynski, Jun Wang, Robert Gaizauskas, Mark Greenwood · 2008
Automated answering of natural language questions is an interesting and useful problem to solve. Question answering (QA) systems often perform information retrieval at an initial stage. Information retrieval (IR) performance, provided by engines such as Lucene, places a bound on overall system performance. For example, no answer bearing documents are retrieved at low ranks for almost 40% of questions.