Tree-Adjoining Grammars (TAG) have been used both for syntactic parsing, with sentential grammars, and for discourse parsing, with discourse grammars. But the modeling of discourse connectives (coordinate conjunctions, subordinate conjunctions , adverbs, etc.) in TAG-based formalisms for discourse differ from their modeling in sentential grammars. Because of this mismatch, an intermediate, not ...

This paper describes a new interpretation of Tree Adjoining Grammars (TAG) that allows the embedding of TAG in the unification framework in a manner consistent with the declarative approach taken in this framework. In the new interpretation we present in this paper, the objects manipulated by a TAG are considered to be descriptions of trees. This is in contrast to the traditional view that in a...

Speech recognition typically involves three types of models; an acoustic model, a phonetic dictionary and a language model. The primary purpose of the language model is to decide if a sentence is part of the language, and optionally how likely it is. N -gram is a common type of language model which predicts upcoming words based on a series of prior words. While efficient a problem with this typ...

This paper looks at an algorithm due to Chen and Dill for estimating the partition functions of a restricted subclass of double-stranded polymers, and shows how it can be translated into a context-free grammar, so that their algorithm reduces to a variant of the CKY parsing algorithm. Our formulation clarifies the structure of Chen and Dill’s algorithm, leading to revised complexity analyses an...

In this paper, we study the behavior of some of the most popular parsing algorithms for Tree Adjoining Grammars (TAG). To this end, we apply a compilation technique allowing automatic transformation of parsing schemata into efficient implementations of their corresponding algorithms; which allows us to compare the performance of different parsers in an homogeneous environment. In our study, we ...

In this paper we present a scheme to extend a recognition algorithm for Context-Free Grammars (CFG) that can be used to derive polynomial-time recognition algorithms for a set of formalisms that generate a superset of languages generated by CFG. We describe the scheme by developing a Cocke-Kasami-Younger (CKY)-like pure bottom-up recognition algorithm for Linear Indexed Grammars and show how it...

The task of natural language generation is devided into three major subtasks (see, e.g., Levelt 89]): macro planning (MAP), the elaboration of the communicative intention as a sequence of subgoals and the selection of information to be expressed in order to realize these communicative goals, micro planning (MIP), the further shaping of each speech act to bring it into the format required by the...

In this paper, we show how a CCG-like account for coordination can be constructed in the framework of lexicalized tree-adjoining grammars (TAGs) (Joshi, 1987; Schabes et al., 1988; Schabes, 1990). 2. In particular, we show how a fixed constituency can be maintained at the level of the elementary trees of lexicalized TAGs and yet be able to achieve the kind of flexibility needed for dealing with...

Developing a Tree Adjoining Grammar which contains the information necessary for building the basic compositional semantics of sentences is a highly complex engineering task. To ensure consistency, ease of writing, of maintainance and of debugging, it is therefore important that this information be described at the appropriate level of abstraction. In the first part of this paper (sections 2 an...

Linear tree-adjoining grammars (TAGs), by analogy with linear context-free grammars, are treeadjoining grammars in which at most one symbol in each elementary tree can be rewritten (adjoined or substituted at). Uemura et al. (1999), calling these grammars simple linear TAGs (SLTAGs), show that they generate a class of languages incommensurate with the context-free languages, and can be recogniz...