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Page 3886 of Mathematical Reviews Vol. , Issue 97F [page]

1997 Mathematical Reviews  
parsing algorithm for K -depth languages.  ...  The algorithm for parsing k-depth languages which the authors develop is similar in spirit to the Cocke-Younger-Kasami (CYK) algorithm for context-free languages.  ... 

Derivatives of Parsing Expression Grammars

Aaron Moss
2017 Electronic Proceedings in Theoretical Computer Science  
This paper introduces a new derivative parsing algorithm for recognition of parsing expression grammars.  ...  Derivative parsing is shown to have a polynomial worst-case time bound, an improvement on the exponential bound of the recursive descent algorithm.  ...  This changes the derivative tree into a directed acyclic graph (DAG), and also bounds the increase in derivative size and computation time, allowing this parsing algorithm to achieve the polynomial time  ... 
doi:10.4204/eptcs.252.18 fatcat:rta36b7mifd47pkofvd45a5vnq

Simplified Parsing Expression Derivatives [chapter]

Aaron Moss
2020 Lecture Notes in Computer Science  
This paper presents a new derivative parsing algorithm for parsing expression grammars; this new algorithm is both simpler and faster than the existing parsing expression derivative algorithm presented  ...  This new algorithm improves on the worst-case space and runtime bounds of the previous algorithm by a linear factor, as well as decreasing runtime by about half in practice.  ...  Derivative parsing presents a different trade-off, with low common-case memory usage paired with a polynomial time bound.  ... 
doi:10.1007/978-3-030-40608-0_30 fatcat:kao6hlfa2baitflsbyxwie4ukm

Learning Efficient Disambiguation [article]

Khalil Sima'an
1999 arXiv   pre-print
This dissertation analyses the computational properties of current performance-models of natural language parsing, in particular Data Oriented Parsing (DOP), points out some of their major shortcomings  ...  for successful specialization.  ...  Ambiguity-reduction specialization takes place off-line by using a tree-bank that is representative of a limited domain of language use. • it presents deterministic polynomial-time algorithms for parsing  ... 
arXiv:cs/9906006v2 fatcat:of6kbtp255clbbboy4m73ite6q

Bounded size dictionary compression: SCk-completeness and NC algorithms

Sergio De Agostino, Riccardo Silvestri
2003 Information and Computation  
When the size of the dictionary is Oðlog k nÞ, the problem of computing the LZ2 compression is shown to be hard for the class of problems solvable simultaneously in polynomial time and Oðlog k nÞ space  ...  For simpler heuristics (SWAP, RESTART, FREEZE), practical parallel algorithms are given.  ...  Acknowledgments We thank Raymond Greenlaw for suggesting several improvements of the paper. We also thank Pierre McKenzie for helpful comments and discussions.  ... 
doi:10.1016/s0890-5401(02)00013-5 fatcat:5dtvou3xlve7dnwjsht4mo2swy

Quantum Language Processing [article]

Nathan Wiebe, Alex Bocharov, Paul Smolensky, Matthias Troyer, Krysta M Svore
2019 arXiv   pre-print
We further provide a new training method for learning quantum Harmony operators that describe a language.  ...  We present a representation for linguistic structure that we call a Fock-space representation, which allows us to embed problems in language processing into small quantum devices.  ...  It follows that the relatively simple code for maximizing Harmony on a given candidate parse tree should be just a subroutine in a higher level algorithm that enumerates all feasible parse trees, or, for  ... 
arXiv:1902.05162v1 fatcat:d4peucjpbjgknh6rb232y5ve7q

A note on the complexity of comparing succinctly represented integers, with an application to maximum probability parsing [article]

Kousha Etessami, Alistair Stewart, Mihalis Yannakakis
2014 arXiv   pre-print
Problem 1 is easily decidable in polynomial time using a simple iterative algorithm. Problem 2 is much harder.  ...  We describe one application: P-time maximum probability parsing for arbitrary stochastic context-free grammars (where ϵ-rules are allowed).  ...  Thanks to Howard Karloff and Igor Shparlinski for comments on an earlier draft. In particular, thanks to Igor for pointing out references [2, 8] on efficient factor refinement.  ... 
arXiv:1304.5429v3 fatcat:y3upbueyybh63nfcrc6xmwj3yu

Characterizing Valiant's algebraic complexity classes

Guillaume Malod, Natacha Portier
2008 Journal of Complexity  
We also show that for circuits of polynomial depth and unbounded size these models all have the same expressive power and can be used to characterize a uniform version of VNP.  ...  As a consequence we get simpler proofs for known results such as the equality of the classes VNP and VNP e or the completeness of the Determinant for VQP, and new results such as a characterization of  ...  All these steps can be done in time polynomial in n because checking the direct connection language can be done in polynomial time, and the parse tree is of polynomial size.  ... 
doi:10.1016/j.jco.2006.09.006 fatcat:j25vuys4czbtnghbzvto3sp35q

LL (1) Parser versus GNF inducted LL (1) Parser on Arithmetic Expressions Grammar: A Comparative Study

Hassan Ali, Muhammad Shumail Naveed, Dilawar Naseem, Jawaid Shabbir
2020 Quaid-e-awam University research journal of engineering science & technology  
The study described that GNF based LL(1) parser for arithmetic take fewer steps than conventional LL(1) grammar.  ...  A transformation method is defined which converts the selected grammar into a Greibach normal form that is further converted into a GNF based parser through a method proposed in the study.  ...  [41] presented another algorithm that can parse the PEG's algorithm with worst-case space and rum time complexity of linear time. Lurent et. al.  ... 
doi:10.52584/qrj.1802.14 fatcat:2gy57uthefakbgrstfncminxqm

A Note on the Complexity of Comparing Succinctly Represented Integers, with an Application to Maximum Probability Parsing

Kousha Etessami, Alistair Stewart, Mihalis Yannakakis
2014 ACM Transactions on Computation Theory  
Problem 2 (inequality testing): Decide whether a b1 Problem 1 is easily decidable in polynomial time using a simple iterative algorithm. Problem 2 is much harder.  ...  We describe one application: P-time maximum probability parsing for arbitrary stochastic context-free grammars (where ǫ-rules are allowed). captures all of polynomial time in the unit-cost arithmetic RAM  ...  Thanks to Howard Karloff and Igor Shparlinski for comments on an earlier draft. In particular, thanks to Igor for pointing out references [2, 8] on efficient factor refinement.  ... 
doi:10.1145/2601327 fatcat:cflevkqko5hnthfshnqnaq36g4

Depth-bounding is effective: Improvements and evaluation of unsupervised PCFG induction

Lifeng Jin, Finale Doshi-Velez, Timothy Miller, William Schuler, Lane Schwartz
2018 Proceedings of the 2018 Conference on Empirical Methods in Natural Language Processing  
Moreover, parsing results on English, Chinese and German show that this bounded model with a new inference technique is able to produce parse trees more accurately than or competitively with state-ofthe-art  ...  The present work instead applies depth bounds within a chart-based Bayesian PCFG inducer (Johnson et al., 2007b) , where bounding can be switched on and off, and then samples trees with and without bounding  ...  Acknowledgments The authors would like to thank the anonymous reviewers for their helpful comments. Computations for this project were partly run on the Ohio Supercomputer Center (1987).  ... 
doi:10.18653/v1/d18-1292 dblp:conf/emnlp/JinDMSS18 fatcat:kxytcssbjjarto4ieza6wdar3e

Complexity of computations

Michael O. Rabin
1977 Communications of the ACM  
Directions for new research are discussed.  ...  That was the formal citation, but there is a less formal side to this presentation.  ...  We take as base the number 2 k, so that 0 _< o~i, /3~ < 2 k, and use algorithms for finding a + b, a * b. 2.4 Parsing Expressions in Context-Free Languages The scope of complexity theory is by no means  ... 
doi:10.1145/359810.359816 fatcat:jlj6n4wzlbgd7aq524lsmx2i5u

Data-Oriented Language Processing. An Overview [article]

Rens Bod, Remko Scha
1996 arXiv   pre-print
During the last few years, a new approach to language processing has started to emerge, which has become known under various labels such as "data-oriented parsing", "corpus-based interpretation", and "  ...  In this paper we give an in-depth discussion of a data-oriented processing model which employs a corpus of labelled phrase-structure trees.  ...  Finally, Sima'an (1996b) proved that there is no deterministic polynomial time algorithm for finding the most probable parse of a sentence in STSG (i.e., the problem of computing the most probable parse  ... 
arXiv:cmp-lg/9611003v1 fatcat:lbfbavlmpvbu3itq44purog4zq

A Quasi-polynomial-time Algorithm for Sampling Words from a Context-Free Language

Vivek Gore, Mark Jerrum, Sampath Kannan, Z. Sweedyk, Steve Mahaney
1997 Information and Computation  
A quasi-polynomial-time algorithm is presented for sampling almost uniformly at random from the n-slice of the language L(G) generated by an arbitrary context-free grammar G.  ...  (The n-slice of a language L over an alphabet is the subset L\ n of words of length exactly n.) The time complexity of the algorithm is " ?  ...  The main and obvious open question is whether a truly polynomial-time algorithm exists for sampling from the n-slice of a context-free language, or for estimating its size.  ... 
doi:10.1006/inco.1997.2621 fatcat:yk6v2bwkmvgq3drs4oscnu3ixi

Simplified Parsing Expression Derivatives [article]

Aaron Moss
2018 arXiv   pre-print
This paper presents a new derivative parsing algorithm for parsing expression grammars; this new algorithm is both simpler and faster than the existing parsing expression derivative algorithm presented  ...  A proof of correctness for the new algorithm is included in this paper, a result not present in earlier work.  ...  Analysis In [12] , Moss demonstrated the polynomial worstcase space and time of his algorithm with an argument based on bounds on the depth and fanout of the DAG formed by his derivative expressions.  ... 
arXiv:1808.08893v1 fatcat:uhob4bukybfk5dyuqxysfmfmxe
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