CKY Parsing with Independence Constraints

نویسندگان

  • Joseph Irwin
  • Yuji Matsumoto
چکیده

The CKY algorithm is an important component in many natural language parsers. We propose a novel type of constraint for context-free parsing called independence constraints. Based on the concept of independence between words, we show how these constraints can be used to reduce the work done in the CKY algorithm. We demonstrate a classifier which can be used to identify boundaries between independent words in a sentence using only surface features, and show that it can be used to speed up a CKY parser. We investigate the trade-off between speed and accuracy, and indicate directions for improvement.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Neural Shift-Reduce CCG Semantic Parsing

We present a shift-reduce CCG semantic parser. Our parser uses a neural network architecture that balances model capacity and computational cost. We train by transferring a model from a computationally expensive loglinear CKY parser. Our learner addresses two challenges: selecting the best parse for learning when the CKY parser generates multiple correct trees, and learning from partial derivat...

متن کامل

Iterative CKY Parsing for Probabilistic Context-Free Grammars

This paper presents an iterative CKY parsing algorithm for probabilistic contextfree grammars (PCFG). This algorithm enables us to prune unnecessary edges produced during parsing, which results in more efficient parsing. Since pruning is done by using the edge’s inside Viterbi probability and the upper-bound of the outside Viterbi probability, this algorithm guarantees to output the exact Viter...

متن کامل

Accelerating the CKY Parsing Using FPGAs

The main contribution of this paper is to present an FPGA-based implementation of an instance-specific hardware which accelerates the CKY (Cocke-Kasami-Younger) parsing for context-free grammars. Given a context-free grammar G and a string x, the CKY parsing determines whether G derives x. We have developed a hardware generator that creates a Verilog HDL source to perform the CKY parsing for an...

متن کامل

Efficient Implementation of the Cky Algorithm

When the CKY algorithm is presented in Natural Language Processing literature, it is often is described in high-level pseudo code. The implementation details of the CKY algorithm, despite being critical to efficiency, are rarely (if ever) discussed. In this paper I discuss multiple implementation approaches, and optimizations on these approaches to increase parsing time an order of magnitude wh...

متن کامل

Parallelizing the CKY and Earley Parsing Algorithms

Context-free parsing algorithms are one of the oldest and most well-understood aspects of natural language processing. Efforts to reduce the time complexity of these algorithms have produced two particularly popular algorithms: the Cocke-Kasami-Younger (CKY) bottomup parsing algorithm [5, 9], and the Earley top-down parsing algorithm [2, 3]. However, despite these efforts, parsing remains a tim...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2015