Metaphors in Wordnets:From Theory to Practice

Antonietta AlongeUniversity of Perugia

Italy

Birte LönnekerUniversity of Hamburg,

GermanyScientific Research,Center ZRC SAZU,

Slovenia

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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

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Metaphor as Regular Polysemy

Metaphorical extension of word senses is a kind of regular polysemy:

He arrived when we were 20.

He left us after some time.

‘came here’

‘was born’

‘went away’

‘died’

New metaphorical meanings are usually extensions of existing conceptual mappings

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Cross-Cultural Variation of Metaphors Language-specific conceptual metaphors

ANGER IS IN THE HEART: Zulu (Kövecses 2002)

Universal conceptual metaphors can 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

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Towards a Better Metaphor Representation in Wordnets I

Conventional metaphorical sense extensions should be: present connected to their ‘basic’ senses

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Towards a Better Metaphor Representation in Wordnets II Data which could help identify novel

metaphorical expressions should 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

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Towards a Better Metaphor Representation in Wordnets

Infiammarsi2 to flare up1

DERIVED_FROM_LITERAL

to flare up2

Infiammarsi1

Italian WordNet ILI

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Evaluating and Adding Metaphor Information

Use Cognitive Metaphor theory and Text corpora to

Check which concepts of a source domain have the expected conventional metaphorical 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

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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?

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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

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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 event may

‘come into existence’, as can people or living entities in general

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Results (2) Comparison with ItalWordNet

Two IWN synsets express the metaphor:1. (gloss) “to be the outcome or consequence” 2. (gloss) “to arise, to come up, of an event”

Create one synset Add the link to the ‘literal’ sense Create a Composite ILI Unit

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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

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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: Parto is a cross-pos-synonym of partorire No metaphorical sense is encoded in IWN

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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!)

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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 ILIs corresponding to both synsets

A link from {gestazione 1, gravidanza 1} to the Composite ILI is created

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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

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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