Parsing Some Constrained Grammar Formalisms
Paper · 1993 · K Vijay-Shanker and David J. Weir
Summary
Vijay-Shanker and Weir carry context-free recognition techniques over to a few mildly context-sensitive formalisms, namely Tree Adjoining Grammars (TAG), Linear Indexed Grammars (LIG), and a variant of Combinatory Categorial Grammars (CCG). These formalisms control derivations with unbounded stacks, either explicitly or implicitly. Storing whole stacks in a parse table would make recognition exponential. The authors observe that in LIG and CCG, different branches of a derivation never share a stack. So the context-freeness property still holds, and a bounded amount of information per table cell is enough.
They develop a pure bottom-up, CKY-style recognizer for LIG in a binary normal form. Each table cell stores only the top part of a stack plus a pointer to the cell where the rest of that stack can be recovered. They prove the algorithm correct by induction, then adapt it to CCG and TAG. The result is a reusable recipe for polynomial-time recognition of stack-controlled grammars. At the time, it gave the only known polynomial-time recognizer for CCG.
Key points
- The central problem is unbounded stacks. Path sets of CFG, HG, and TAG derivation trees are regular languages, while those of LIG and CCG are context-free. Naive stack storage therefore leads to exponential time and space.
- The LIG normal form allows at most two right-hand-side symbols, split into a primary and a secondary constituent. The primary constituent always yields the distinguished child, which inherits the stack.
- The table P[i, d] for input a₁…aₙ (an n × n array) records that an object derives the substring starting at position i with length d. Entries keep the nonterminal and top stack symbols, plus "terminator" pointers to other entries for the rest of the stack.
- The pointer trick only works directly when at least two stack symbols are recorded (k ≥ 2). The authors handle the remaining cases with a threshold on stack length (TTC) and a "TC-property" in the correctness proof.
- The scheme builds on equivalence proofs linking LIG, TAG, CCG, and Head Grammars. The authors note it could be adapted to Earley-style parsing or Lang's (1990) framework.
Fields, topics and concepts
📚 Shelves 2The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 works
🧭 Topics 1Research subjects and languages the work is about.Syntax & grammar formalisms · 214 works
Cite
Cite as K Vijay-Shanker and David J. Weir. 1993. Parsing Some Constrained Grammar Formalisms. Computational Linguistics.
@article{vijayshanker1993parsing,
title = {{Parsing Some Constrained Grammar Formalisms}},
author = {K Vijay-Shanker and David J. Weir},
journal = {Computational Linguistics},
year = {1993},
url = {https://aclanthology.org/J93-4002/}
}References
- Aho, A. V. (1968). "Indexed grammars — An extension to context free grammars." J. ACM, 15, 647-671. find
- Duske, J., and Parchmann, R. (1984). "Linear indexed languages." Theoretical Comput. Sci., 32, 47-60. find
- Gazdar, G. (1988). "Applicability of indexed grammars to natural languages." In Natural Language Parsing and Linguistic Theories, edited by U. Reyle and C. Rohrer. D. Reidel, 69-94. find
- Joshi, A. K. (1985). "How much context-sensitivity is necessary for characterizing structural descriptions — tree adjoining grammars." In Natural Language Processing — Theoretical, Computational and Psychological Perspective, edited by D. Dowty, L. Karttunen, and A. Zwicky. Cambridge University Press,… find
- Joshi, A. K.; Levy, L. S.; and Takahashi, M. (1975). "Tree adjunct grammars." ]. Comput. Syst. Sci., 10(1), 136-163. find
- Kasami, T. (1965). "An efficient recognition and syntax algorithm for context-free languages." Technical Report AF-CRL-65-758, Air Force Cambridge Research Laboratory, Bedford, MA. find
- Lang, B. (1990). "Towards a uniform formal framework for parsing." In Current Issues in Parsing Technology, edited by M. Tomita. Kluwer Academic Publishers, 153-171. find
- Pareschi, R., and Steedman, M. J. (1987). "A lazy way to chart-parse with categorial grammars." In Proceedings, 25th Meeting of the Association for Computational Linguistics, 81-88. find
- Pollard, C. (1984). Generalized Phrase Structure Grammars, Head Grammars and Natural Language. Doctoral dissertation, Stanford University. find
- Steedman, M. (1986). "Combinators and grammars." In Categorial Grammars and Natural Language Structures, edited by R. Oehrle, E. Bach, and D. Wheeler. Foris, 417-442. find
- Steedman, M. J. (1985). "Dependency and coordination in the grammar of Dutch and English." Language, 61:523-568. find
- Tomita, M. (1988). "Graph-structured stack and natural language parsing." In Proceedings, 26th Meeting of the Association for Computational Linguistics, 248-257. find
- Vijay-Shanker, K. (1987). A study of tree adjoining grammars. Doctoral dissertation, University of Pennsylvania, Philadelphia, PA. find
- Vijay-Shanker, K., and Joshi, A. K. (1985). "Some computational properties of tree adjoining grammars." In Proceedings, 23rd Meeting of the Association for Computational Linguistics, 82-93. find
- Vijay-Shanker, K., and Weir, D. J. (In press). "The equivalence of four extensions of context-free grammars." Mathematical Systems Theory. find
- Vijay-Shanker, K., and Weir, D. J. (1990). find
Updated
This page in Markdown → https://md.research.elamur.ai/free/en/papers/shanker-1993-parsing-some-constrained-grammar-formalisms/