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Graphs are increasingly becoming ubiquitous as models for structured data. A generative model that closely mimics the structural properties of a given set of graphs has utility in a variety of domains. Much of the existing work require that…

Social and Information Networks · Computer Science 2019-02-25 Revanth Reddy , Sarath Chandar , Balaraman Ravindran

Nez is a PEG(Parsing Expressing Grammar)-based open grammar language that allows us to describe complex syntax constructs without action code. Since open grammars are declarative and free from a host programming language of parsers,…

Programming Languages · Computer Science 2015-11-30 Kimio Kuramitsu

Probabilistic context-free grammars (PCFGs) with neural parameterization have been shown to be effective in unsupervised phrase-structure grammar induction. However, due to the cubic computational complexity of PCFG representation and…

Computation and Language · Computer Science 2021-04-29 Songlin Yang , Yanpeng Zhao , Kewei Tu

File formats specify how data is encoded for persistent storage. They cannot be formalized as context-free grammars since their specifications include context-sensitive patterns such as the random access pattern and the type-length-value…

Programming Languages · Computer Science 2023-04-24 Jialun Zhang , Greg Morrisett , Gang Tan

Graph Interpolation Grammars are a declarative formalism with an operational semantics. Their goal is to emulate salient features of the human parser, and notably incrementality. The parsing process defined by GIGs incrementally builds a…

cmp-lg · Computer Science 2009-09-25 John Larcheveque

We present the squirrel parser, a PEG packrat parser that directly handles all forms of left recursion with optimal error recovery, while maintaining linear time complexity in the length of the input even in the presence of an arbitrary…

Programming Languages · Computer Science 2026-01-09 Luke A. D. Hutchison

Probabilistic context free grammars (PCFG) have been the core of the probabilistic reasoning based parsers for several years especially in the context of the NLP. Multi entity bayesian networks (MEBN) a First Order Logic probabilistic…

Artificial Intelligence · Computer Science 2019-01-29 Shrinivasan R Patnaik Patnaikuni , Dr. Sachin R Gengaje

In this paper we demonstrate that $\textit{context free grammar (CFG) based methods for grammar induction benefit from modeling lexical dependencies}$. This contrasts to the most popular current methods for grammar induction, which focus on…

Computation and Language · Computer Science 2020-07-31 Hao Zhu , Yonatan Bisk , Graham Neubig

Probabilistic context-free grammars have a long-term record of use as generative models in machine learning and symbolic regression. When used for symbolic regression, they generate algebraic expressions. We define the latter as equivalence…

Formal Languages and Automata Theory · Computer Science 2022-12-05 Urh Primožič , Ljupčo Todorovski , Matej Petković

Large language models (LLMs) exhibit strong semantic understanding, yet struggle when user instructions involve ambiguous or conceptually misaligned terms. We propose the Language Graph Model (LGM) to enhance conceptual clarity by…

Computation and Language · Computer Science 2025-11-06 Wenchang Lei , Ping Zou , Yue Wang , Feng Sun , Lei Zhao

Prefix parsing asks whether an input prefix can be extended to a complete string generated by a given grammar. In the weighted setting, it also provides prefix probabilities, which are central to context-free language modeling,…

Computation and Language · Computer Science 2026-05-05 Clemente Pasti , Andreas Opedal , Timothy J. O'Donnell , Ryan Cotterell , Tim Vieira

Transformer-based language models are effective but complex, and understanding their inner workings and reasoning mechanisms is a significant challenge. Previous research has primarily explored how these models handle simple tasks like name…

Computation and Language · Computer Science 2025-05-20 Zeyuan Allen-Zhu , Yuanzhi Li

PGA, short for ProGram Algebra, describes sequential programs as finite or infinite (repeating) sequences of instructions. The semigroup C of finite instruction sequences was introduced as an equally expressive alternative to PGA. PGA…

Programming Languages · Computer Science 2010-03-09 Stephan Schroevers

Grammatical Evolution (GE) is one of the most popular Genetic Programming (GP) variants, and it has been used with success in several problem domains. Since the original proposal, many enhancements have been proposed to GE in order to…

Neural and Evolutionary Computing · Computer Science 2021-03-16 Jessica Mégane , Nuno Lourenço , Penousal Machado

The left-corner transformation (Rosenkrantz and Lewis, 1970) is used to remove left recursion from context-free grammars, which is an important step towards making the grammar parsable top-down with simple techniques. This paper generalizes…

Computation and Language · Computer Science 2023-11-29 Andreas Opedal , Eleftheria Tsipidi , Tiago Pimentel , Ryan Cotterell , Tim Vieira

Graph-based semantic representations are valuable in natural language processing, where it is often simple and effective to represent linguistic concepts as nodes, and relations as edges between them. Several attempts has been made to find…

Formal Languages and Automata Theory · Computer Science 2021-05-10 Johanna Björklund , Frank Drewes , Anna Jonsson

Compound probabilistic context-free grammars (C-PCFGs) have recently established a new state of the art for unsupervised phrase-structure grammar induction. However, due to the high space and time complexities of chart-based representation…

Computation and Language · Computer Science 2023-10-24 Yanpeng Zhao , Ivan Titov

We describe a compiler which translates a set of HPSG lexical rules and their interaction into definite relations used to constrain lexical entries. The compiler ensures automatic transfer of properties unchanged by a lexical rule. Thus an…

cmp-lg · Computer Science 2008-02-03 Walt Detmar Meurers , Guido Minnen

Grammatical Error Correction (GEC) should not focus only on high accuracy of corrections but also on interpretability for language learning. However, existing neural-based GEC models mainly aim at improving accuracy, and their…

Computation and Language · Computer Science 2022-03-15 Masahiro Kaneko , Sho Takase , Ayana Niwa , Naoaki Okazaki

Lambek Grammars (LG) are a computational modelling of natural language, based on non-commutative compositional types. It has been widely studied, especially for languages where the syntax plays a major role (like English). The goal of this…

Computation and Language · Computer Science 2020-02-04 Valentin D. Richard