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Consistent Identification in the Limit of Rigid Grammars from Strings Is NP-hard [chapter]

Christophe Costa Florêncio
2002 Lecture Notes in Computer Science  
These procedures take a set of structures (strings labeled with derivational information) as input and yield a set of hypotheses in the form of grammars.  ...  The time complexity of these functions however was still left an open question. In this paper we will show that the learning functions for these learnable classes are all NP-hard.  ...  Keywords: contextfree languages, categorial grammar, identification in the limit, complexity In [Gol67] the notion identification in the limit was introduced.  ... 
doi:10.1007/3-540-45790-9_5 fatcat:s2kt6u7fubbvvcvud35jmk52ay

Some Classes of Regular Languages Identifiable in the Limit from Positive Data [chapter]

François Denis, Aurélien Lemay, Alain Terlutte
2002 Lecture Notes in Computer Science  
Used with permission. p. 28 Beyond EDSM p. 37 Consistent Identification in the Limit of Rigid Grammars from Strings Is NP-hard p. 49 Some Classes of Regular Languages Identifiable in the Limit  ...  k-testable Tree Languages and Applications p. 199 Fast Learning from Strings of 2-Letter Rigid Grammars p. 213 Learning Locally Testable Even Linear Languages from Positive Data p. 225 Inferring  ... 
doi:10.1007/3-540-45790-9_6 fatcat:nmlknwqoyfbybhb6rpomqrn7qy

Finding Consistent Categorial Grammars of Bounded Value: A Parameterized Approach [chapter]

Christophe Costa Florêncio, Henning Fernau
2010 Lecture Notes in Computer Science  
It was shown that for most of these classes, selecting a grammar from the class that is consistent with the data is NP-hard.  ...  These classes were shown to be learnable from text, in the technical sense of identifiability in the limit from positive data.  ...  This was originally neglected, since the consistency problem was studied as an aspect of learning problems, specifically of identification in the limit.  ... 
doi:10.1007/978-3-642-13089-2_17 fatcat:dq3dofgbpvgkvfxotvkz7jkyxa

On families of categorial grammars of bounded value, their learnability and related complexity questions

Christophe Costa Florêncio, Henning Fernau
2012 Theoretical Computer Science  
It was shown that, for most of these classes, selecting a grammar from the class that is consistent with given data is NP-hard.  ...  As far as the authors are aware, we have obtained the first such results for grammar induction problems and, more generally, learning problems in the identification in the limit paradigm. 2 Apart from  ...  Acknowledgments We would like to thank the two anonymous reviewers for their comments. The research was partly funded by the University of Trier, which allowed the first author to visit Trier.  ... 
doi:10.1016/j.tcs.2012.05.016 fatcat:smkfmludnva2plrjoolamhh2ii

Fast Learning from Strings of 2-Letter Rigid Grammars [chapter]

Yoav Seginer
2002 Lecture Notes in Computer Science  
It is well-known that certain classes of classical categorial grammars are learnable, within Gold's paradigm of identification in the limit, from positive examples.  ...  In the search for classes which can be learned efficiently from strings, we study the class of 2-letter rigid grammars, which is the class of classical categorial grammars with an alphabet of two letters  ...  Introduction It is well-known that certain classes of classical categorial grammars are learnable, within Gold's paradigm of identification in the limit, from positive examples.  ... 
doi:10.1007/3-540-45790-9_17 fatcat:sl4xqlen3vbtvcelpeqsuhfpem

Encyclopedia of cognitive science

2003 ChoiceReviews  
A categorial lexicon assigns one or more types to the atomic elements of a language; the assembly of form and meaning is accounted for in terms of the rules of inference for these types seen as formulas  ...  Cross-linguistic variation results from extending the invariant core of the grammar logic with facilities for structural reasoning.  ...  Kanazawa (1998) has studied formal learning theory for categorial grammar within Gold's paradigm of identification in the limit on the basis of positive data.  ... 
doi:10.5860/choice.41-0046 fatcat:tpjsphfjqrebdnp7bt4zrng46y

Combinatory Categorial Grammar [chapter]

Mark Steedman
2011 Taking Scope  
One way to provide that explanation is to show that the constraints stem from limitations in automata-theoretic power of the grammar itself.  ...  The minimum apparatus besides competence grammar that is required for processing consists of the characteristic automaton for the relevant class of grammars (including its possibly limited working memories  ... 
doi:10.7551/mitpress/9780262017077.003.0006 fatcat:2uteapar2jd7tiku77rylcdkla

Combinatory Categorial Grammar [chapter]

Mark Steedman, Jason Baldridge
2011 Non-Transformational Syntax  
One way to provide that explanation is to show that the constraints stem from limitations in automata-theoretic power of the grammar itself.  ...  The minimum apparatus besides competence grammar that is required for processing consists of the characteristic automaton for the relevant class of grammars (including its possibly limited working memories  ... 
doi:10.1002/9781444395037.ch5 fatcat:nfovjbngrrfwxjfiqjlkiv5g6u

Combinatory Categorial Grammar [chapter]

M. Steedman, J. Baldridge
2006 Encyclopedia of Language & Linguistics  
One way to provide that explanation is to show that the constraints stem from limitations in automata-theoretic power of the grammar itself.  ...  The minimum apparatus besides competence grammar that is required for processing consists of the characteristic automaton for the relevant class of grammars (including its possibly limited working memories  ... 
doi:10.1016/b0-08-044854-2/02028-9 fatcat:ks4myyz6zna25jm2l433h2xqgi

Improving dynamic software analysis by applying grammar inference principles

Neil Walkinshaw, Kirill Bogdanov, Mike Holcombe, Sarah Salahuddin
2008 Journal of Software Maintenance and Evolution Research and Practice  
Grammar inference is a family of machine learning techniques that aim to infer grammars from a sample of sentences in some (unknown) language.  ...  Dynamic analysis is a family of techniques in the domain of software engineering that attempts to infer rules that govern the behaviour of software systems from a sample of executions.  ...  ACKNOWLEDGEMENTS The authors thank the anonymous referees for their valuable comments.  ... 
doi:10.1002/smr.373 fatcat:4cbdwhpg5bg7vlgj7qnw4y657y

Fundamental methodological issues of syntactic pattern recognition

Mariusz Flasiński, Janusz Jurek
2013 Pattern Analysis and Applications  
Methodological considerations on crucial issues in areas of string and graph grammar-based syntactic methods are made.  ...  Fundamental open problems, which are frontiers of syntactic pattern recognition are discussed in the paper.  ...  It results from a uniform rigid structure of strings. However, in case of graph grammars we have to specify how to embed the righthand side graph in the rest-graph in an explicit way.  ... 
doi:10.1007/s10044-013-0322-1 fatcat:42h3kj4zhjdkpoiwjl5plbyece

Learning Recursive Automata from Positive Examples

Isabelle Tellier
2006 Revue d'intelligence artificielle : Revue des Sciences et Technologies de l'Information  
Finally, new learnable subclasses of categorial grammars are defined, for which learning from strings is nearly not more expensive than from structures. RÉSUMÉ.  ...  The relation between these generalized automata and categorial grammars is studied in detail.  ...  is also NP-hard (Florêncio, 2001) .  ... 
doi:10.3166/ria.20.775-804 fatcat:s4kxnkdtefb7daokgwnihiaq5i

Parameterized Complexity in Cognitive Modeling: Foundations, Applications and Opportunities

I. van Rooij, T. Wareham
2007 Computer journal  
In this paper, we consider the particular benefits of the parameterized complexity framework for identifying sources of intractability in cognitive models.  ...  We review existing applications of the parameterized framework to this end in the domains of perception, action and higher cognition.  ...  complexity results can and should play in linguistics.  ... 
doi:10.1093/comjnl/bxm034 fatcat:p2x6vjt24vbvhn7uh5ifqj4dri

An Extension of Finite-state Markov Decision Process and an Application of Grammatical Inference [chapter]

Takeshi Shibata, Ryo Yoshinak
2008 Reinforcement Learning  
A context-free grammar (CFG) is a quadruple denoted by , where V is a finite set of nonterminal symbols, Σ is a finite set of terminal symbols, R ⊂ V×(V ∪ Σ)* is a finite set of production rules, and S  ...  ∈V is the start symbol.  ...  Identification in the limit of right-unique simple grammars from positive data 4.1 Learning simple grammars A most rigid theoretical model for learning concepts would be identification in the limit proposed  ... 
doi:10.5772/5276 fatcat:2rtphxd6sne2jftvmxqc3zf3qi

Clinical Text Summarization with Syntax-Based Negation and Semantic Concept Identification [article]

Wei-Hung Weng, Yu-An Chung, Schrasing Tong
2020 arXiv   pre-print
In the era of clinical information explosion, a good strategy for clinical text summarization is helpful to improve the clinical workflow.  ...  Our research objective is to use the biomedical ontology with semantic information, and take the advantage from the language hierarchical structure, the constituency tree, in order to identify the correct  ...  The capability of using regular expression in linear string structure is interpretable but limited since human assembles language in a hierarchical geometrical structure rather than linear way [Hamburger  ... 
arXiv:2003.00353v1 fatcat:n4kqfp24ubh3fcsjlp7xxjabdi
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