A parallel algorithm is presented for recognizing the class of languages generated by tree adjoining grammars, a tree rewriting system which has applications in computational Linguistics. This class of languages is known to properly include all context-free languages; for example, the non-context-free sets {anbncn} and {ww) are in this class. It is shown that the recognition problem for tree ad...

Deterministic parsers have been proposed for two-level control grammars. These parsers are efficient in both time and space and are simple extensions of the standard LL(I) and LR( 1) parsers for deterministic context free languages. An important advantage of the parsers proposed here is that existing parser generator tools can be augmented to generate them from grammar specifications. Since the...

We study parsing of tree adjoining grammars with particular emphasis on the use of shared forests to represent all the parse trees deriving a well-formed string. We show that there are two distinct ways of representing the parse forest one of which involves the use of linear indexed grammars and the other the use of context-free grammars. The work presented in this paper is intended to give a g...

Mobile intention recognition is the problem of inferring a mobile agent’s intentions from her spatio-temporal behavior. The intentions an agent can have in a specific situation depend on the spatial context, and on the spatially contextualized behavior history. We introduce two spatially constrained grammars that allow for modeling of complex constraints between space and intentions, one based ...

Tree adjoining grammars (TAG) represent a derivational formalism to construct trees from a given set of initial and auxiliary trees. We present a logical language that simultaneously describes the generated TAG-tree and the corresponding derivation tree. Based on this language we formulate constraints indicating whether a tree and a derivation tree mean a valid TAGgenerated tree. A method is pr...

This paper presents an adaptation of the Earley algorithm (EARLEY, 1968) for parsing with lexicalized tree-adjoining grammars (LTAGs). This algorithm constructs the derivation tree following a top-down strategy and verifies the valid prefix property. Many earlier algorithm do not have both of this properties (ScHABES, 1994). The Earley-like algorithm described in (SCHABES and Josm, 1988) verifi...

A number of grammar formalisms were proposed in 80’s, such as Lexical Functional Grammars, Generalized Phrase Structure Grammars, and Tree Adjoining Grammars. Those formalisms then started to put a stress on lexicon, and were called as lexicalist (or lexicalized) grammars. Representative examples of lexicalist grammars were Head-driven Phrase Structure Grammars (HPSG) and Lexicalized Tree Adjoi...

This paper continues a program extending results related to the descriptive characterization of the CFLs in terms of deenability in the weak monadic second-order theory of trees to the TALs and the entire hierarchy of Weir's Control Languages. Previously, we have shown that the languages in this hierarchy can be characterized by deenability in the weak monadic second-order theories of a general...

In this paper, we introduce SEMTAG, a free and open software architecture for the development of Tree Adjoining Grammars integrating a compositional semantics. SEMTAG differs from XTAG in two main ways. First, it provides an expressive grammar formalism and compiler for factorising and specifying TAGs. Second, it supports semantic construction.

The aim of this paper is to describe an approach to semantic representation in the Lexicalized Tree Adjoining Grammars (LTAG)[1] paradigm. We show how to use all the informations contained in the two representation structures provided by the LTAG formalism in order to provide a dependency graph.