Reducing Syntactic Complexity for Information Extraction from Japanese Requirement Specifications

In software development, ambiguities in requirements described in natural language (NL) prevent the application of formal approaches, posing a difficulty that has heretofore been avoided in two main ways: discovery based on formal specifications generated from NL requirements, and the creation of non-ambiguous NL requirements. In the former, NL is more expressive and does not rely on the user‘s expertise, but instead makes the automatic generation of formal specifications difficult. The latter facilitates the automatic generation of formal specifications and has the advantage of reduced syntactic complexity, but in exchange for reduced expressiveness of NL. In this paper, we take an approach that allows users to describe highly expressive NL requirements and reduces syntactic complexity to support the automatic generation of formal specifications from NL requirements. We also propose an information extraction method using syntactic patterns of low syntactic complexity. Applying our method to practical requirement sentences reveals that it is effective in reducing the complexity of information extraction rules. We expect that our method can support the automatic generation of formal specifications from NL requirements without compromising the expressive power of the language.