Multi-dimensional feature merger for question answering

In this paper, we introduce new features for question-answering systems. These features are inspired by the fact that justification of the correct answer (out of many candidate answers) may be present in multiple passages. Our features attempt to combine evidence from multiple passages retrieved for a candidate answer. We present results on two data-sets: Jeopardy! and Doctor's Dilemma. In both data-sets, our features are ranked highest in correlation with gold class (in the training data) and significantly improve the performance of our existing QA system, Watson. © 2012 The COLING.