An ambiguity hierarchy of weighted context-free grammars

• Published in: Theoretical computer science Vol. 974; p. 114112
• Main Authors: Inoue, Yusuke, Hashimoto, Kenji, Seki, Hiroyuki
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 29.09.2023
• Subjects: Ambiguity; Pumping lemma; Weighted context-free grammar; Weighted context-free grammar; Pumping lemma; Ambiguity

Weighted context-free grammar (WCFG) is a quantitative extension of context-free grammar (CFG). It is known that unambiguous weighted automata (WA), finitely-ambiguous WA, polynomially-ambiguous WA and general WA over the tropical semiring have different expressive powers. We prove that there exists...