Constructive Learning of Context-Free Languages with a Subpansive Tree [chapter]

Noriko Sugimoto, Takashi Toyoshima, Shinichi Shimozono, Kouichi Hirata
2000 Lecture Notes in Computer Science  
A subpansive tree is a rooted tree that gives a partial order of nonterminal symbols of a context-free grammar. We formalize subpansive trees as background knowledge of CFGs, and investigate query learning of CFGs with the help of subpansive trees. We show a restricted class of CFGs, which we call hierarchical CFGs, is efficiently learnable, while it is unlikely to be polynomial-time predictable.
doi:10.1007/978-3-540-45257-7_22 fatcat:zin6dd722ngktmyjppnyul62pq