Disclosed are an answer selection method for a question answering system. With the method and system, a sentence distributed representation of a question and an answer is generated by adopting a hierarchical length-adaptive neural network structure with a purpose of extracting high-quality sentence features by using different neural feature extractors according to a length of an input sentence. First, one word distributed representation is generated for each word in the input sentence by connecting one fixed word embedding and one finely-adjusted word embedding. Next, a BiLSTM-based feature extractor is used for a short sentence and a Transformer-based feature extractor is used for a long sentence. Finally, a sentence vector representation for measuring a correlation between a question and a candidate answer is generated by using an attention pooling layer considering an interaction between a question sentence and an answer sentence.
Answer selection method for question answering system and the system