# Consistent Identification in the Limit of Rigid Grammars from Strings Is NP-hard

@inproceedings{Florncio2002ConsistentII, title={Consistent Identification in the Limit of Rigid Grammars from Strings Is NP-hard}, author={Christophe Costa Flor{\^e}ncio}, booktitle={ICGI}, year={2002} }

In [Bus87] and [BP90] some 'discovery procedures' for classical categorial grammars were defined. 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.In [Kan98] learning functions based on these discovery procedures were studied, and it was shown that some of the classes associated with these functions can be identified in the limit (i.e. are learnable) from strings, by a computable function…

## 20 Citations

### Finding Consistent Categorial Grammars of Bounded Value: A Parameterized Approach

- Computer ScienceLATA
- 2010

Kanazawa ([8]) has studied the learnability of several parameterized families of classes of categorial grammars. These classes were shown to be learnable from text, in the technical sense of…

### Learning Recursive Automata from Positive Examples

- Computer ScienceRev. d'Intelligence Artif.
- 2006

This theoretical paper studies how to translate finite state automata into categorial grammars and back, and shows that the generalization operators employed in both domains can be compared and that their result can always be represented by generalized automata, called "recursive automata ".

### A Learnable Class of CCGs from Typed Examples

- Computer Science
- 2003

A new way of considering learning Categorial Grammars from semantic knowledge is presented, and the hypothesis that semantic types, in the usual sense, are general information making a distinction between facts, is made.

### Partial Learning Using Link Grammars Data

- Computer Science, LinguisticsICGI
- 2004

This article proposes to adapt this kind of symbolic learning to natural languages by assuming that a small part of the grammar to be learned is given as input to compensate the combinatorial explosion of the learning algorithm.

### A Learnable Class of Classical Categorial Grammars from Typed Examples

- Computer Science
- 2008

The main result is that for every CCG, a new subclass of CCGs with good properties from a language-theoretic point of view is defined.

### When Categorial Grammars Meet Regular Grammatical Inference

- Computer ScienceLACL
- 2005

It is proved that every unidirectional categorial grammar, and thus every context-free language, can be represented by a new kind of finite-state generative model called a recursive automaton.

### Grammatical Inference: Learning Automata and Grammars

- Computer Science
- 2010

The author describes a number of techniques and algorithms that allow us to learn from text, from an informant, or through interaction with the environment that concern automata, grammars, rewriting systems, pattern languages or transducers.

### Proceedings of FGVienna: The 8th conference on Formal Grammar

- Computer Science
- 2003

It is proved that the languages of link structured lists of words associated to rigid link grammars have finite elasticity and a learning algorithm is shown and this result leads to the learnability of rigid or k-valued link Grammars learned from strings.

### Advances in Learning Formal Languages

- Computer Science, Linguistics
- 2011

An overview in the advances related to the learning of formal languages i.e. development in the grammatical inference research is presented, and the case of context-free grammars, challenges, recent trends etc., is cited.

### How to Split Recursive Automata

- Computer ScienceICGI
- 2008

In this paper, we interpret in terms of operations applying on extended finite state automata some algorithms that have been specified on categorial grammars to learn subclasses of context-free…

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