Constructive Learning of Context-Free Languages with a Subpansive Tree
نویسندگان
چکیده
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.
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