Metaphors in Wordnets: From Theory to Practice

1. Antonietta Alonge University of Perugia Italy Birte Lönneker University of Hamburg, Germany ScientificResearch, Center ZRC SAZU, Slovenia Metaphors in Wordnets:From Theory to Practice

2. Introduction: Cognitive Metaphor Theory • Metaphorical linguistic expressions are manifestations of conceptual metaphors • Metaphorical structures • are present in our minds • relate a (concrete) source conceptual domain with a(more abstract) target conceptual domain: • As we travel down life's path... • He just sails through life.(Lakoff et al. 1991)  Conceptual metaphor: LIFE IS A JOURNEY LREC Conference, Lisbon, Portugal

3. Metaphor as Regular Polysemy • Metaphorical extension of word senses is a kind ofregular polysemy: • He arrived when we were 20. • He left usafter some time. ‘came here’ ‘was born’ ‘went away’ ‘died’ New metaphorical meanings are usually extensions of existing conceptual mappings LREC Conference, Lisbon, Portugal

4. Cross-Cultural Variation of Metaphors • Language-specific conceptual metaphors • ANGER IS IN THE HEART: Zulu (Kövecses 2002) • Universalconceptual metaphorscan show cultural variation at a specific level: • ANGER IS HEAT • English: ANGER IS A HOT FLUID IN A CONTAINER He’s just blowing off steam • Italian: *Lui sta liberando vapore LREC Conference, Lisbon, Portugal

5. Towards a Better Metaphor Representation in Wordnets I • Conventional metaphorical sense extensions should be: • present • connected to their‘basic’ senses LREC Conference, Lisbon, Portugal

6. Towards a Better Metaphor Representation in Wordnets II • Data which could help identify novel metaphoricalexpressionsshould be provided: • at a level higher than synset level • e.g. in EWN in the form of a language-independent, coarse-grained sense group: • a Composite InterLingual-Index (ILI) unit • showing potential relations to the individual languages LREC Conference, Lisbon, Portugal

7. Towards a Better Metaphor Representation in Wordnets Infiammarsi2 to flare up1 DERIVED_FROM_LITERAL to flare up2 Infiammarsi1 Italian WordNet ILI EQ_METAPHOR EQ_SYNONYM EQ_SYNONYM EQ_METAPHOR LREC Conference, Lisbon, Portugal

8. Evaluating and Adding Metaphor Information Use Cognitive Metaphor theory and Text corpora to • Check which concepts of a source domainhave the expected conventionalmetaphorical senses in corpora • Check if concepts in a source domain are properly related within wordnets • Identify conventional metaphorical word senses missing in wordnets • Identify potential novel metaphorical senses LREC Conference, Lisbon, Portugal

9. Example Analysis • Conceptual metaphor: • CREATING IS BIRTHING • Conceptual source domain: • BIRTHING • Lexical instantiations of the source domain: birth, to give birth, (to be) born, pregnancy, midwife, delivery, delivery room, ... Which lexical instantiations are used metaphorically in a large corpus? LREC Conference, Lisbon, Portugal

10. Results (1) from the Italian PAROLE Online Corpus • Nascita (‘birth’) can be used metaphorically: • la nascita di un Governo della Regione (the birth of a Government of the Region) • Comparison with ItalWordNet: • This metaphorical sense is present • Add the link to the ‘literal’ sense • Create a Composite ILI Unit LREC Conference, Lisbon, Portugal

11. Results (2) • Nascere (‘to be born’) can be used metaphorically: • dalla sua fatica è nato questo lungo studio (this study was born (derived) from his ... work) • nacque fra loro un’amicizia profonda (a deep friendship was born between them) • da qui nacque la polemica (from this the argument was born (arose)) • An object, a state (relation), or an eventmay ‘come into existence’,as can people or living entities in general LREC Conference, Lisbon, Portugal

12. Results (2) • Comparison with ItalWordNet • Two IWN synsets express themetaphor: • (gloss) “to be the outcome orconsequence” • (gloss) “to arise, to come up,of an event” • Create one synset • Add the link to the ‘literal’ sense • Create a Composite ILI Unit LREC Conference, Lisbon, Portugal

13. Results (3) • Partorire (‘to give birth’)can be used metaphorically: • È difficile partorire un nuovo spettacolo (It is difficult to give birth to (to produce) a new show) • Comparison with ItalWordNet: • Linked to nascere by a cause relation • Metaphorical sense correctly encoded • Add the link to the ‘literal’ sense • Create a Composite ILI Unit LREC Conference, Lisbon, Portugal

14. Results (4) • Parto (‘childbirth,delivery’) can be used metaphorically: • il passaggio all’Unione Monetaria sarà un parto difficile (the passing to the Monetary Union will be a difficult delivery(achievement)) • Comparison with ItalWordNet: • Partois a cross-pos-synonym of partorire • No metaphorical sense is encoded in IWN LREC Conference, Lisbon, Portugal

15. Results (5) • Gestazione (‘pregnancy,gestation’) can be used metaphorically: • Ignoravo che il decreto fosse in gestazione (I ignored that the decree was in gestation (in progress)) • Comparison with ItalWordNet: • Literal sense in {gestazione, gravidanza} • A metaphorical sense is encoded only for gestazione, but also gravidanza can be used metaphorically (infrequent/novel use!) LREC Conference, Lisbon, Portugal

16. Displaying Potential Novel Instantiations of Metaphors • How to ensure that applications can interpret metaphorical uses of gravidanza? Remember: • {gestazione 1, gravidanza 1} is a “literal” synset • {gestazione 2} is a metaphorical synset  We cluster the literal and the metaphorical ILIscorresponding to both synsets • A link from {gestazione 1, gravidanza 1} to the Composite ILI is created LREC Conference, Lisbon, Portugal

17. Consequences for Applications: an Example • Automated sense clustering • Group similar senses:useful e.g. for WSD • But on which grounds should senses be regarded as ‘similar’? • depends partly on application (Chugur, Gonzalo & Verdejo 2000; 2002) • Senses related by metaphor belong to different semantic fields and tend to occur in distinct documents: • they should be distinguished e.g. for IR LREC Conference, Lisbon, Portugal

18. Future work • Clustering of ILI synsets (GWA website) • On-going development of metaphor databases • One for German and French (in Hamburg) • One for Italian (in Perugia) • Complete proposals for enhancing metaphor representations in EWN LREC Conference, Lisbon, Portugal