W.C. Rounds and R.T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 15th Annual IEEE Symposium on Logic and Computer Science, pages 39--43, 1986.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....constructor types with LOGIN s feature types. Feature Logic [Smo88a, Smo89] is a decidable logic that generalizes Ait Kaci s formalism by adding negation and quantification. Feature Logic makes explicit that Ait Kaci s terms, the feature descriptions developed by computational linguists [KB82, RK86, Joh88] and the knowledge representation language KL ONE [BS85, LB87, Neb89, SSS91, NS90] are all closely related members of the same family of logics. These logics offer attributive concept descriptions that are interpreted as sets and are built from sorts and binary relations (called ....

.... term calculus and led to the development of Feature Logic [Smo88a, Smo89] a decidable logic that generalizes Ait Kaci s formalism by adding negation and quantification. Feature Logic makes explicit that Ait Kaci s terms, the feature descriptions developed by computational linguists [KB82, RK86, Joh88] and the knowledge representation language KL ONE [BS85, LB87, Neb89, SSS91, NS90] are all closely related members of the same family of logics. These logics offer attributive concept descriptions that are interpreted as sets and are built from sorts and binary relations (called ....

William C. Rounds and Robert T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, Mass., 1986.

....descriptions in logic programming has been advocated and studied [2, 3, 4, 17, 16] Essentially, feature de scriptions provide a logical version of records, a data structure found in many programming languages. Feature descriptions have been proposed in various forms with various formalizations [1, 13, 9, 15, 5, 10]. We will follow the logical approach pioneered by [15] which accommodates feature descriptions as standard first order formulae interpreted in firstorder structures. In this approach, a semantics for We appreciate discussions with Joachim Niehren and RMf Treinen who read a draft version of ....

....of a prime formula 3X7 is defined as follows: 3X71 : r[711120 r) CIx=0 or t=xex or r xelx . The proper closure of a prime formula fi is de fined as follows: ifil : r ifil [ r is a proper path constraint . Proposition 7. 6 If 13 is a prime formula and r We now know that the closure [13], taken as an infinite conjunction, is entailed by 13. We are going to show that, conversely, 13 is entailed by certain finite subsets of its closure [13] An access function for a prime formula fi = is a function that maps every x 12(7) X to the rooted path xe, and every x X to a rooted path ....

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W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing hnguistic information. In Proceedings of the Ist IEEE Symposium on Logic in Computer Science, pages 38-43, Boston, MA, 1986.

....features, which are functional attributes. Figure 1, for instance, shows the description of a linguistic object that may represent the sentence John sings a song . The features appear as edges of the graph. The terminal nodes are atoms representing primitive linguistic objects. Kasper and Rounds [10, 17] were the first to capture the relation between feature descriptions and linguistics objects in terms of a logic. Subsequently, Johnson [6] and Smolka [22, 23] realized that feature logics can be modeled straightforwardly in Predicate Logic. In this approach, which underlies the present paper, ....

....is simply a structure that interprets atoms as pairwise distinct individuals and features as unary partial functions that are undefined on atoms. In addition, one can have sorts, which are interpreted as sets of individuals. One popular syntax for feature descriptions are so called feature terms [10, 17, 23], which are expressions denoting sets in feature algebras. The basic feature term forms are given by S Gamma a j A j p: S j p#q j S u S j S t S j :S; where a stands for atoms, A stands for sorts, and p and q stand for words over features. Given a feature algebra, a denotes the singleton ....

W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, Mass., 1986.

....descriptions in logic programming has been advocated and studied [3, 4, 5, 6, 21] Essentially, feature descriptions provide a logical version of records, a data structure found in many programming languages. Feature descriptions have been proposed in various forms with various formalizations [1, 2, 14, 18, 11, 20, 7, 12]. We will follow the logical approach pioneered by [20] which accommodates feature descriptions as standard first order formulae interpreted in first order structures. In this approach, a semantics for feature descriptions can be given by means of a feature theory (i.e. a set of closed feature ....

W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, MA, 1986.

....has been recognized as a powerful description language for feature trees. For the first area, this is immediate by the role of constraints in constraint logic programming [19] and in concurrent constrained based languages [26] while in the second area different approaches have been proposed. [24, 27, 20, 25] have advocated the use of predicate logic as feature description languages. 6] argues that predicate logic is the right language to express phenomena in both fields, and that feature trees constitute the canonical semantical model. Feature trees [4] are possibly infinite, finitely branching ....

William C. Rounds and Robert Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the First Symposium on Logic in Computer Science, pages 38--43, Cambridge, MA, June 1986. IEEE Computer Society.

....[46] and Johnson s Attribute Value Logic [16] employ boolean combinations of equations built from features (used as unary functions) atoms (used as constants) and variables. Kay s Functional Unification Grammar [24, 25, 26] Ait Kaci s Term Calculus [2, 3, 4] and Kasper and Rounds logic [23, 39] employ set denoting expressions, called feature terms in this paper, that come in different syntactic guises (Figure 2 gives an example) Feature terms have much in common with the concept descriptions of terminological logics [5, 33, 34] used in knowledge representation. In fact, Ait Kaci s ....

....the edges departing from it must be pairwise distinct. Moreover, every inner node of a feature graph must be a variable, and every terminal node must be either an atom or a variable. Feature graphs can be seen as finite deterministic automata, which is the formalization given by Kasper and Rounds [23, 39]. In contrast to Kasper and Rounds, however, we admit cyclic feature graphs. Formally, an f edge from x to s is a triple xfs such that x is a variable, f is a feature, and s is either a variable or an atom. A feature graph is either a pair (a; where a is an atom and ; is the empty set, or a ....

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W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, MA, 1986.

....common practice to reason about the properties of formalisms for linguistic description within the framework of formal logic. A number of first order theories have been proposed to serve the purpose, ranging from classical first order predicate calculus to numerous variants of non classical logics [RK86, KR86] elsewhere dubbed designer logics [Joh90] These latter approaches have been criticized for cutting the field o# the wealth of results in classical logic without real benefits since it has never been shown that any of the non classical devices proposed was indeed necessary [Joh90] The same ....

Rounds, William C. and Robert Kasper. 1986. A complete logical calculus for record structures representing linguistic information. In : Symposium on Logic in Computer Science, IEEE Computer Society

....of these formalisms to express complex constraints involving negation and disjunction of equality constraints, besides arising formal theoretical problems leads to a NP hard satisfiability problem. From a formal point of view the problem is well understood after the foundational works of [RK86,Smo89] establishing Feature Logics. It turns out that the standard model for feature logics, namely rational trees, has a close relationship with the standard algebra of rational trees in Logic Programming and with its complete axiomatization presented in [Mah88] As a matter of fact it can be ....

W.C. Rounds and R.T. Kasper. A complete logical calculus for record structures representing linguistic information. In Symposium on Logic in Computer Science, IEEE Computer Society, 1986.

....side. So why is this intuitive understanding not sufficient 10 Briscoe Copestake (1999) provide an interesting discussion of lexical rules in a typed default feature structure framework (Lascarides et al. 1996, Lascarides Copestake 1999) which is an extension of a Kasper Rounds logic (Rounds Kasper 1986, Moshier Rounds 1987, Carpenter 1992) The ontological assumptions and formal properties of a KasperRounds logic differ in crucial respects from those of an Attribute Value logic (Johnson 1988, Smolka 1988, King 1989) and King (1994) shows that only the latter is compatible with the ....

Rounds, W. C. & Kasper, R. T., 1986. A Complete Logical Calculus for Record Structures Representing Linguistic Information. In Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science, Cambridge, MA, USA. pp. 38--43.

....interpreted as being true or false of linguistic objects, not of feature structures which stand in a one to one relation with linguistic objects, as in HPSG II. Apart from the philosophical consequences (which will not be discussed here) this gap between HPSG II and King (1989) can 13 cf. Rounds and Kasper (1986), Moshier and Rounds (1987) and Carpenter (1992) 14 cf. Johnson (1988) Smolka (1988) and King (1989) 15 Note that the theories in an HPSG II architecture are formulated using implications on types; in fact, even stronger implicative statements with complex antecedents are used. We will ....

Rounds, W. C., and R. T. Kasper. 1986. A Complete Logical Calculus for Record Structures Representing Linguistic Information. In Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science, Cambridge, MA, USA, 38--43.

....in so called unification grammars [13, 12] developed for natural language processing, and also the formalisms of Mukai [17, 18] These early feature structure formalism were presented in a nonlogical form. Major steps in the process of their understanding and logical reformulation are the articles [20, 23, 11, 22]. Feature trees, the feature tree structure T , and the axiomatization of T were first given in [6] The paper is organized as follows. Section 2 defines the basic notions and discusses the differences in expressivity between Herbrand and FT. Section 3 gives a basic simplification system that ....

W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, MA, 1986.

....a formalism in which constraints involving simple (atomic) negation may be handled with essentially no increase in computational complexity over the standard unification algorithm. Unfortunately, the situation is not so favorable in the context of more general constraints. Rounds and Kasper [RK86] have shown that testing for satisfaction of general logical constraints on feature structures is an NP complete problem, and so 2 0. INTRODUCTION barring a major unexpected breakthrough in the theory of computational complexity, the best known algorithms for solving such problems will remain of ....

....requiring that fi( be defined. Then every MBFS will have exactly one initial state, identified by fi( 3 1. 5 Differences between our definition and those of others Our definition is based upon the automaton theoretic definition of ordinary feature structures which is due to Kasper and Rounds [RK86]. In addition to allowing multiple initial states, there are a few other differences. First of all, we do not legislate away the possibility that the automaton may be cyclic; that is, that it may have a state q for which there is a nonempty string with ffi (q; q. While the issue of whether ....

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Rounds, W. C. and Kasper, R., "A complete logical calculus for record structures representing linguistic information," in: Proceedings of the First IEEE Symposium on Logic in Computer Science, pp. 38--43, 1986.

....Value logics, for it made it very clear that the distinction logicians draw between a language and its semantics was a fruitful way of looking at puzzles involving disjunctive feature structures. However Kasper and Rounds proved relatively few results about L KR . They give some near the end of [22], but the bulk of this paper is devoted to de ning the relevant languages and proving a completeness result for the negation free fragment of L. Incidentally, most of the results Kasper and Rounds give are not obtained using modal techniques; although they spotted the similarity between modal ....

W. Rounds and R. Kasper, 1986, A Complete Logical Calculus for Record Structures Representing Linguistic Information, in Proceedings of the 15th Annual Symposium on Logic in Computer Science, Cambridge, Massachussets.

....Historically, the impetus for making this distinction was motivated by the diculties involved in giving a precise account of AVMs that employed disjunction or negation. The distinction was rst introduced by Pereira and Sheiber [33] and it underpins the in uential work of Kaspar and Rounds [26][41][42] Thus the move towards full Boolean expressivity marked an important turning point in the development of Attribute Value formalisms. What do computational linguists do with AVMs The answer is, they try to unify them. Intuitively, unifying two AVMs means forming another AVM that combines all ....

....2 L [ f0g: M j= hl 1 i hl k i hl 0 1 i hl 0 m i[w] i 9w 0 (wR l 1 : R l k w 0 wR l 0 1 : R l 0 m w 0 ) L KR models the path equation mechanism of PATR II. The negation free fragment of this language was rst de ned and studied by Kaspar and Rounds [26][41]; a more detailed presentation of their work may be found in [42] Further logical investigations of L KR may be found in [30] and [6] It is instructive (and will later prove technically useful) to examine L, L N and L KR from the more general perspective provided by modal correspondence ....

Rounds, W. and Kaspar, R.: 1986, A Complete Logical Calculus for Record Structures Representing Linguistic Information, in Proceedings of the 15th Annual Symposium on Logic in Computer Science, Cambridge, Massachussets.

....are not only well typed, in the sense already defined for HPSG sorts, but also that a feature structure of a type T must be specified for all the features appropriate for T. Terms are represented in ALE through an extended version of a notation known as Attribute Value Logic, first presented by Rounds and Kasper (1986). What follows is the specification, in Backus Naur form, of possible Attribute Value Descriptions (henceforth: AVD) provided in Carpenter (1993) 25 desc : type variable ( feature : desc ) desc , desc ) desc ; desc ) desc ) Briefly, a feature ....

Rounds, W. C. and R. T. Kasper (1986) A Complete Logical Calculus for Record Structures Representing Linguistic Information. In Proceedings of the 15th Annual Symposium on Logic in Computer Science.

....author was with IBM Deutschland. The author s article [23] is a more recent work on feature logics. 1 1 Introduction This paper presents a set description logic that generalizes and integrates formalisms that have been developed for knowledge representation [1, 2] and computational linguistics [13, 21, 11, 9]. The logic comes with an open world model theoretic semantics, where admissible worlds can be required to satisfy a classification scheme postulated by means of a sort lattice. The logic supports the typically partial description of objects using sorts and features as primitives. It is not ....

....for parsing and generating natural language. A unification method for feature descriptions consists of a normal form that exhibits inconsistency and an algorithm that, given two normal feature descriptions s and t, computes a normal feature description equivalent to s u t. 5 Rounds and Kasper [21] were the first to come up with a logical formalization of feature descriptions (without complements and with constants rather than sorts) Their logic has a fixed interpretation, where feature descriptions denote sets of feature structures. Feature structures are consistent, unionfree feature ....

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W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 1st 37 IEEE Symposium on Logic in Computer Science, pages 38--43, Boston, MA, 1986.

.... reconstruction of PATR II in terms of a denotational semantics [ Pereira Shieber 84 ] 3 The work of Karttunen led to major extensions of PATR II, concerning disjunction, atomic negation, and the use of cyclic structures [ Karttunen 84 ] Kasper and Rounds seminal work [ Kasper Rounds 86; Rounds Kasper 86 ] is important in many respects: it clarified the connection between feature structures and finite automata, gave a logical characterization of the notion of disjunction, and presented complexity results for the first time (see [ Kasper Rounds 90 ] for a summary) Mark Johnson then enriched the ....

William C. Rounds and Robert T. Kasper. A Complete Logical Calculus for Record Structures Representing Linguistic Information. In: Proceedings of the 15th Annual Symposium of the IEEE on Logic in Computer Science, 1986.

....checked with feature structures, and after parsing the meaning of the language utterance can (hopefully) be extracted from them. The structure of our feature structures is similar to the more traditional form of feature structures as used in the patr ii system (Shieber 1986) and those defined by Rounds and Kasper (1986). Typed feature structures are defined as rooted DAGs (directed acyclic graphs) with labeled edges and nodes. More formally, we can define a typed feature structure tfs as a 2 tuple ht; featuresi, where t 2 Types, the set of all types, and features is a (possibly empty) set of features. A ....

Rounds, W. C., and Kasper, R. T. (1986). A complete logical calculus for record structures representing linguistic information. In Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science, 39--43. Cambridge, MA.

....here is between expressive power and tractability: the empty fragment, for example, is obviously tractable, but it is not very expressive . The most popular fragment which emerged from this research is known as feature constraints , originally introduced in the context of linguistics [15] to represent syntactic information in Lexical Functional Grammars. The satisfiability problem in this case is also known as feature constraint solving . Traditionally, feature constraints are built from atomic constraints which are either sort or label constraints. A sort is a unary relation, ....

Rounds, W., Kasper, R.: A Complete Logical Calculus for Record Structures Representing Linguistic Information. Proc. 1st IEEE Symp. on Logic in Computer Science, Boston, MA, Jun. 1986, pp. 38--43

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W.C. Rounds and R.T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 15th Annual IEEE Symposium on Logic and Computer Science, pages 39--43, 1986.

No context found.

Rounds, W. and Kasper, R.: 1986, A Complete Logical Calculus for Record Structures Representing Linguistic Information, in Proceedings of the 15th Annual Symposium on Logic in Computer Science, Cambridge, Massachussets.

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Williams C. Rounds and R. Kasper. A complete logical calculus for record structures representing linguistic information. In IEEE Symposium on Logic in Computer Science, 1986.

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Rounds, W. and R. Kasper 1994. A complete logical calculus for record structures representing linguistic information, in Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science, 39-43, Cambrdige, MA.

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W. C. Rounds and R. T. Kasper. A complete logical calculus for record structures representing linguistic information. In Proceedings of the 15th Annual IEEE Symposium on Logic in Computer Science, Cambridge, MA, 1986.

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Williams C. Rounds and R. Kasper. A complete logical calculus for record structures representing linguistic information. In IEEE Symposium on Logic in Computer Science, 1986.

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