文法推断研究的历史和现状

Grammatical Inference: Retrospect and Prospect

文法推断属于形式语言的归纳学习问题，它研究如何从语言的有限信息出发，通过归纳推断得到语言的语法定义．文章综述了文法推断研究的历史和现状．首先阐述文法推断的理论模型，接着罗列上下文无关文法类及其非平凡子类、隐马尔可夫模型以及随机上下文无关文法的推断方法，最后简介文法推断的应用，并展望其发展趋势．

Grammatical Inference (GI) is a problem of inductive learning of formal languages, which deals with how to obtain the grammatical description of a formal language from the given finite data drawn from the language. In this paper, the author provides a survey of the history and recent advances in GI field. The author first presents some learning models for GI, then enumerates the methods for GI with an emphasis on the results concerning the inference of context free grammar class and its some subclasses, hidden Markov models, and stochastic pontext-free grammar class. At last, the author briefly gives some applications of GI as well as the future directions of GI research.