tailieunhanh - Báo cáo khoa học: "A Meta-Level Grammar: Redefining Synchronous TAG for Translation and Paraphrase"

In applications such as translation and paraphrase, operations are carried out on grammars at the meta level. This paper shows how a meta-grammar, defining structure at the meta level, is useful in the case of such operations; in particular, how it solves problems in the current definition of Synchronous TAG (Shieber, 1994) caused by ignoring such structure in mapping between grammars, for applications such as translation. Moreover, essential properties of the formalism remain unchanged. | A Meta-Level Grammar Redefining Synchronous TAG for Translation and Paraphrase . Mark Dras Microsoft Research Institute Department of Computer Science Macquarie University Australia Abstract In applications such as translation and paraphrase operations are carried out on grammars at the meta level. This paper shows how a meta-grammar defining structure at the meta level is useful in the case of such operations in particular how it solves problems in the current definition of Synchronous TAG Shieber 1994 caused by ignoring such structure in mapping between grammars for applications such as translation. Moreover essential properties of the formalism remain unchanged. 1 Introduction A grammar is among other things a device by which it is possible to express structure in a set of entities a grammar formalism the constraints on how a grammar is allowed to express this. Once a grammar has been used to express structural relationships in many applications there are operations which act at a meta level on the structures expressed by the grammar for example lifting rules on a dependency grammar to achieve pseudo-projectivity Kahane et al 1998 and mapping between synchronised Tree Adjoining Grammars TAGs Shieber and Schabes 1990 Shieber 1994 as in machine translation or syntax-to-semantics transfer. At this meta level however the operations do not themselves exploit any structure. This paper explores how in the TAG case using a meta-level grammar to define meta-level structure resolves the flaws in the ability of Synchronous TAG S-TAG to be a representation for applications such as machine translation or paraphrase. This paper is set out as follows. It describes the expressivity problems of S-TAG as noted in Shieber 1994 and shows how these occur also in syntactic paraphrasing. It then demonstrates illustrated by the relative structural complexity which occurs at the meta level in syntactic paraphrase how a meta-level grammar resolves the representational

• Báo cáo khoa học
• A Meta Level Grammar
• Redefining Synchronous TAG
• Translation and Paraphrase
• báo cáo khoa học
• mô hình ngôn ngữ
• xử lý ngôn ngữ tự nhiên
• Bài giảng Xử lý ngôn ngữ tự nhiên
• Ngôn ngữ tự nhiên
• Kỹ thuật lập trình
• Xử lý nhập nhằng ngữ nghĩa
• Xử lý ngữ nghĩa
• Xử lý ngôn ngữ
• Natural Language Processing
• Ngôn ngữ lập trình
• Nhập nhằng cấu trúc
• Tri thức về ngôn ngữ
• Mô hình n gram
• Dịch máy
• Phương pháp dịch máy
• Hiểu ngôn ngữ
• Phân tích ngữ nghĩa
• Phân loại tin tự động
• Biểu diễn vị từ
• Thuộc tính về sự kiện
• Thuộc tính về sự kiện
• Mô hình ngôn ngữ Google Book N grams
• Mô hình ngôn ngữ KenLM
• Phương pháp làm mịn
• Tách từ tiếng Việt
• Gán nhãn từ loại
• Phân tích cú pháp
• Nghĩa từ vựng
• Phân giải nhập nhằng từ
• Phân loại văn bản
• Lexical chain
• Phản hồi thông tin
• Bài toán PTCP
• Cấu trúc ngữ pháp
• Phân tích cú pháp xác suất
• CKY kết hợp xác suất
• Văn phạm phi ngữ cảnh xác suất
• Hình thái học