William C. Rounds and Alexis ManasterRamer. A logical version of functional grammar. In Proceedings of The 25th Annual Meeting of the Association for Computational Linguistics, 1987. 104  Home/Search   Document Not in Database   Summary   Related Articles   Check

....TAGs [10] The hasic parsing operation of the system is S graph unification (S unification) This is essentially ordinary feature structure unification augmented with an operation of label unification to build the stratified features characteristic of SFG. RELATED WORK Rounds and Manaster Ramer [9] suggested encoding multiple strata in terms of a level attribute, using path equations to state correspondences across strata. Unfortunately, unchangee relations in a stratum must be explicitly carried over via path equations to the next stratum. Even worse, these carry over equations ....

....to be functional. However, as shown in the example, the individual It signs are not. Moreover, the lengths of the labels can vary, and this crucial property is how SFG avoids the carry over problem. S graphs also include a strict partial order on arcs to represent linear precedence (cf. 3] [9]) The SFG description language in cludes a class of linear precedence statements, e.g. 1] H] means that in a constituent the final subject precedes the head . Given a set T of It signs, a (stratified) feature (or label) is a sequence of It signs which may be closed on the left or right ....

William C. Rounds and Alexis ManasterRamer. A logical version of functional grammar. In Proceedings of The 25th Annual Meeting of the Association for Computational Linguistics, 1987. 104

....for theory development, it can be extraordinarily unperspicuous. This problem has to a certain extent already been encountered in the context of syntactic analysis, and in response various proposals have been made to enrich raw feature term formalisms with recursive type (or sort) speci cations ([RM R87, DE91]) or relational and functional dependencies [Rea91] so as to allow a more transparent encoding of data types. By virtue of their expressiveness, these enrichments typically render the resulting formalisms undecidable. Thus, some care has to be taken to ensure that a given encoding does not ....

Rounds, W. & A. Manaster-Ramer (1987). A Logical Version of Functional Grammar. Proceedings of 25th Annual Meeting of the Association for Computational Linguistics, 6-9 July 1987, Stanford University, Stanford, CA, pp96.

....The word problem of a grammar is to decide for a given sequence of words whether it is a sentence of the grammar. One can show that even the simple formalism outlined above allows for grammars having an undecidable word problem by adapting proofs given by Johnson [16] or Rounds and Manaster Ramer [40] for slightly different formalisms. For grammars employing a decidable constraint logic (that is, it is decidable whether a constraint is satisfiable) the off line parsability constraint [17] is a sufficient condition for the decidability of the word problem. A grammar satisfies the off line ....

.... resemblance with the patr formalism developed at SRI International by Shieber and his colleagues [46, 43] It is also closely related to Bresnan and Kaplan s Lexical Functional Grammar formalism (lfg) 17] Other unification grammar formalisms such as Kay s Functional Unification Grammar (fug) [24, 25, 26, 40], Uszkoreit s Categorial Unification Grammar [49] or Pollard and Sag s hpsg [37] employ different phrase structure rules and different feature constraints. Shieber s [44] introduction to unification based approaches to grammar is an excellent survey of existing formalisms and provides the ....

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W. C. Rounds and A. Manaster-Ramer. A logical version of functional grammar. In Proceedings of the 25th Annual Meeting of the ACL, Stanford University, pages 89--96, Stanford, CA, 1987.

....89 ] Moreover, Smolka gave solutions to problems concerning the complexity and decidability of feature descriptions. Work by Rounds and Manaster Ramer, however, showed that a Kasper Rounds logic enriched with types (type definitions) leads to the undecidability of the satisfiability problem [ Rounds Manaster Ramer 87 ] Later, Smolka 89 ] explained that the undecidability result is due to the use of coreference constraints. Paul King s work aimed to reconstruct a special grammar theory, viz. HPSG, in mathematical terms [ King 89 ] whereas Backofen and Smolka s treatment bridged the gap between logic ....

....ffl Finally, one can define an appropriate :resolved predicate that is suitable for a class of recursive types. 3.5 Theoretical Results It is worth noting that testing for the satisfiability of feature descriptions admitting recursive type equations definitions is in general undecidable. Rounds Manaster Ramer 87 ] were the first to have shown that a Kasper Rounds logic enriched with recursive types allows one to encode a Turing machine hence, deciding satisafiability would imply that the Halting problem is decidable (which is obviously not) Later, Smolka 89 ] argued that the undecidability result is ....

William C. Rounds and Alexis Manaster-Ramer. A Logical Version of Functional Grammar. In: Proceedings of the 25th Annual Meeting of the Association for Computational Linguistics, pp. 89--96, 1987.

....[ Diagne et al. 1995 ] This presupposes that we can properly handle partially expanded typed feature structures. 5 Theoretical Results It is worth noting that testing for the satisfiability of feature descriptions admitting recursive type equations definitions is in general undecidable. Rounds and Manaster Ramer 1987 ] were the first to have shown that a Kasper Rounds logic enriched with recursive types allows one to encode a Turing machine. Later, Smolka 1989 ] argued that the undecidability result is due to the use of coreference constraints. He demonstrated his claim by encoding the word problem of Thue ....

William C. Rounds and Alexis ManasterRamer. A logical version of functional grammar. In Proceedings of the 25th Annual Meeting of the Association for Computational Linguistics, pages 89-- 96, 1987.

....sketched here has been simplified for the purposes of exposition. A more general treatment of these and other formalisms can be found in [12] 5 Related Work The idea of developing feature logics which are sufficiently powerful to encode grammars has been pursued by a number of other researchers [20, 16, 18]. In the work of Pollard [16] and Rounds and Manaster Ramer [20] a grammar is represented by a system of equations which recursively define the meaning of sort or type variables in terms of one another. In contrast, the language described in this paper makes no use of type or sort ....

.... general treatment of these and other formalisms can be found in [12] 5 Related Work The idea of developing feature logics which are sufficiently powerful to encode grammars has been pursued by a number of other researchers [20, 16, 18] In the work of Pollard [16] and Rounds and Manaster Ramer [20], a grammar is represented by a system of equations which recursively define the meaning of sort or type variables in terms of one another. In contrast, the language described in this paper makes no use of type or sort definitions to model recursion. Rather, the power to express recursive ....

Rounds, W.C. and A. Manaster-Ramer (1987) A logical version of Functional Grammar. In Proceedings of the ACL, 25th Annual Meeting, pp. 89--96.

....ffl Finally, one can define an appropriate :resolved predicate that is suitable for a class of recursive types. 4 Theoretical Results It is worth noting that testing for the satisfiability of feature descriptions admitting recursive type equations definitions is in general undecidable. Rounds and Manaster Ramer, 1987 ] were the first having shown that a KasperRounds logic enriched with recursive types allows one to encode a Turing machine. Later, Smolka, 1989 ] argued that the undecidability result is due to the use of coreference constraints. He demonstrated his claim by encoding the word problem of Thue ....

William C. Rounds and Alexis ManasterRamer. A logical version of functional grammar. In Proceedings of the 25th Annual Meeting of the Association for Computational Linguistics, pages 89--96, 1987.

....simple idea leads to a massive reduction of the search space when dealing with incremental expansion (e.g. during parsing) It is worth noting that the satisfiability of feature descriptions admitting recursive type equations definitions is in general undecidable. Rounds and Manaster Ramer [ 11 ] were the first having shown that a Kasper Rounds logic enriched with recursive types allows one to encode a Turing machine. Because our logic is much more richer, we immediately get the same result for TDL. However, one can choose in TDL between a complete expansion algorithm which may not ....

William C. Rounds and Alexis Manaster-Ramer. A logical version of functional grammar. In Proceedings of the ACL, pages 89--96, 1987.

....them. Lambek s syntactic calculi (Lambek, 1958) comprise an early formalization of this idea, which more recently was explored in relation to grammar formalisms based on definite clauses (Colmerauer, 1978; Pereira and Warren, 1980; Pereira and Warren, 1983) and on feature logics (Shieber, 1992; Rounds and ManasterRamer, 1987; Carpenter, 1992) The view of parsing as deduction adds two main new sources of insights and techniques to the study of grammar formalisms and parsing: 1. Existing logics can be used as a basis for new grammar formalisms with desirable representational or computational properties. 2. The modular ....

Rounds, William C. and Alexis Manaster-Ramer. 1987. A logical version of functional grammar. In 25th Annual Meeting of the Association for Computational Linguistics, pages 89--96, Stanford, California. Stanford University.

....the grammatical properties of the string s elements and the linear order between them. Lambek s syntactic calculi [15] comprise an early formalization of this idea, which more recently was explored in relation to grammar formalisms based on definite clauses [7, 23, 24] and on feature logics [35, 27, 6]. The view of parsing as deduction adds two main new sources of insights and techniques to the study of grammar formalisms and parsing: Address correspondence to Stuart M. Shieber, Division of Applied Sciences, Harvard University, Cambridge, MA 02138. Mitsubishi Electric Research Laboratories, ....

William C. Rounds and Alexis Manaster-Ramer. A logical version of functional grammar. In Proceedings of the 25th Annual Meeting of the Association for Computational Linguistics, pages 89--96, Stanford, California, 1987. Stanford University.

....the master modality of Gazdar et al. 23] which we saw in Section 3.2. This extension is due to Moshier [47] If we use a strong logic of this form, then many of the ideas in Kay s functional unification grammar can be captured (for a preliminary attempt to do this, see Rounds and Manaster Ramer [65]) The point is that a grammar can be viewed as a logic incorporating a natural recursion construct. In the following, we will ignore some of the formula syntax introduced by Moshier. Instead we will concentrate on the recursive nature of the logic. We augment our syntax with a set of variables V ....

W. Rounds and A. Manaster Ramer. A logical version of functional grammar. In Proceedings of the 25th Annual Conference of the Association for Computational Linguistics, 1987.

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