language for composed of

Parse Tree Notation (PTN) facilitates the encoding of language translators which transform programs written in high level languages with extensions (e.g. a logic language with object oriented features) into equivalent programs in the original unextended languages (e.g. Prolog). PTN does

Parse trees are fundamental syntactic structures in both computa-tional linguistics and compilers construction. We argue in this paper that, in both fields, there are good incentives for model-checking sets of parse trees for some word according to a context-free grammar. We put forward

We consider methods for compressing parse trees, especially techniques based on statistical modeling. We regard a sequence of productions corresponding to a suffix of the path from the root of a tree to a node as the context of a node. The contexts are augmented with branching information

Abstract We consider methods for compressing parse trees, espe-cially techniques based on statistical modeling. We regard a sequence of productions corresponding to a suffix of thepath from the root of a tree to a node x as the context ofa node x. The contexts are augmented with branching in

and dependency parsing models. Second, for identifiable models, how do we estimate the parameters efficiently? EM suffers from local optima, while recent work using spectral methods [1] cannot be directly applied since the topology of the parse tree varies across sentences. We develop a strategy, unmixing, which

Parse trees are indispensable to the existing tree-based translation models. However, there exist two major challenges in utilizing parse trees: 1) For most language pairs, it is hard to get parse trees due to the lack of syntactic resources for training. 2) Numerous parse trees are not compatible

This paper surveys the theoretical literature on fixed-to-variable-length lossless source code trees, called code trees, and on variable-length-to-fixed lossless sounce code trees, called parse trees. Huffman coding [ l] is the most well known code tree problem, but there are a number

is in the creation of systems to carry out transformation of interrogative to indicative sentences, a rst step in a question-answering system. It is argued that the clustering provides a means to navigate the space of parses assigned to large question sets. A tree-distance analogue of vector-space notion of centroid

Recently, Dubé and Feeley presented a technique that makes lexical analyzers able to build parse trees for the lexemes that match regular expressions. While parse trees usually demonstrate how a word is generated by a context-free grammar, these parse trees demonstrate how a word is generated by a