A Syntactic Parse-Key Tree-Based Approach for English Grammar Question Retrieval

Grammar question retrieval aims to find relevant grammar questions that have similar grammatical structure and usage as the input question query. Previous work on text and sentence retrieval which is mainly based on statistical analysis approach and syntactic analysis approach is not effective in finding relevant grammar questions with similar grammatical focus. In this paper, we propose a syntactic parse-key tree based approach for English grammar question retrieval which can find relevant grammar questions with similar grammatical focus effectively. In particular, we propose a syntactic parse-key tree to capture the grammatical focus of grammar questions according to the blank or answer position of the questions. Then we propose a novel method to compute the parse-key tree similarity between the parse-trees of the question query and the database questions for question retrieval. The performance results have shown that our proposed approach outperforms other classical text and sentence retrieval methods in accuracy.