Sentential query rewriting via mutual reinforcement of paraphrase-coordinate relationships

The effectiveness of retrieval decreases with the increase in query length. We target at sentential queries and propose a method for improving their retrieval performance, called query rewriting . Briefly, given a sentential query, our method acquires paraphrases from the noisy Web and uses them to avoid returning no answers. In particular, since a relation can be represented either intensionally (referred to as paraphrase templates ) or extensionally (referred to as coordinate tuples ), the mutual reinforcement between them are taken into account. The experimental results show that for declarative sentences, the average precision of our method is 68.1%, compared to 44.2% of the baseline. Besides, the relative recall of our method is 95.9%, nearly 3 times compared to that of the baseline. While for questions, the average precision of our method is 46.9%, compared to 39.9% of the baseline. We also show the effectiveness of query rewriting in two applications.