umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Contextual Hyperedge Replacement Grammars for Abstract Meaning Representations
Umeå University, Faculty of Science and Technology, Department of Computing Science. (Foundations of Language Processing)ORCID iD: 0000-0001-7349-7693
Umeå University, Faculty of Science and Technology, Department of Computing Science. (Foundations of Language Processing)
2017 (English)In: Proceedings of the 13th International Workshop on Tree Adjoining Grammars and Related Formalisms / [ed] M. Kuhlmann, T. Scheffler, Association for Computational Linguistics, 2017, p. 102-111Conference paper, Published paper (Refereed)
Abstract [en]

We show how contextual hyperedge replacement grammars can be used to generate abstract meaning representations (AMRs), and argue that they are more suitable for this purpose than hyperedge replacement grammars. Contextual hyperedge replacement turns out to have two advantages over plain hyperedge replacement: it can completely cover the language of all AMRs over a given domain of concepts, and at the same time its grammars become both smaller and simpler.

Place, publisher, year, edition, pages
Association for Computational Linguistics, 2017. p. 102-111
Keywords [en]
Abstract Meaning Representation, DAG Language, Contextual Hyperedge-Replacement
National Category
Computer Sciences
Identifiers
URN: urn:nbn:se:umu:diva-137921OAI: oai:DiVA.org:umu-137921DiVA, id: diva2:1128885
Conference
13th International Workshop on Tree-Adjoining Grammar and Related Formalisms (TAG+13), Umeå, Sweden, September 4-6, 2017
Available from: 2017-07-31 Created: 2017-07-31 Last updated: 2018-11-29Bibliographically approved
In thesis
1. Towards semantic language processing
Open this publication in new window or tab >>Towards semantic language processing
2018 (English)Licentiate thesis, comprehensive summary (Other academic)
Alternative title[sv]
Mot semantisk språkbearbetning
Abstract [en]

The overall goal of the field of natural language processing is to facilitate the communication between humans and computers, and to help humans with natural language problems such as translation. In this thesis, we focus on semantic language processing. Modelling semantics – the meaning of natural language – requires both a structure to hold the semantic information and a device that can enforce rules on the structure to ensure well-formed semantics while not being too computationally heavy. The devices used in natural language processing are preferably weighted to allow for comparison of the alternative semantic interpretations outputted by a device.

The structure employed here is the abstract meaning representation (AMR). We show that AMRs representing well-formed semantics can be generated while leaving out AMRs that are not semantically well-formed. For this purpose, we use a type of graph grammar called contextual hyperedge replacement grammar (CHRG). Moreover, we argue that a more well-known subclass of CHRG – the hyperedge replacement grammar (HRG) – is not powerful enough for AMR generation. This is due to the limitation of HRG when it comes to handling co-references, which in its turn depends on the fact that HRGs only generate graphs of bounded treewidth.

Furthermore, we also address the N best problem, which is as follows: Given a weighted device, return the N best (here: smallest-weighted, or more intuitively, smallest-errored) structures. Our goal is to solve the N best problem for devices capable of expressing sophisticated forms of semantic representations such as CHRGs. Here, however, we merely take a first step consisting in developing methods for solving the N best problem for weighted tree automata and some types of weighted acyclic hypergraphs.

Place, publisher, year, edition, pages
Umeå: Department of Computing Science, Umeå University, 2018. p. 16
Series
Report / UMINF, ISSN 0348-0542 ; 18.12
Keywords
Weighted tree automata, abstract meaning representation, contextual hyperedge replacement grammar, hyperedge replacement grammar, semantic modelling, the N best problem
National Category
Computer Sciences
Research subject
Computer Science; datorlingvistik
Identifiers
urn:nbn:se:umu:diva-153738 (URN)978-91-7601-964-1 (ISBN)
Presentation
2018-12-07, MC413, Umeå, 10:00 (English)
Opponent
Supervisors
Available from: 2018-11-29 Created: 2018-11-28 Last updated: 2018-11-29Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

URL

Authority records BETA

Drewes, FrankJonsson, Anna

Search in DiVA

By author/editor
Drewes, FrankJonsson, Anna
By organisation
Department of Computing Science
Computer Sciences

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 244 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf