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Representing a concept by the distribution of names of its instances Matthijs Westera, Gemma Boleda and Sebastian Pad Representing a concept by the distribution of names of its instances A b h i j e e t G u p t a & Matthijs


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Representing a concept by the distribution of names of its instances

Matthijs Westera, Gemma Boleda and Sebastian Padó

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Representing a concept by the distribution of names of its instances

Matthijs Westera, Gemma Boleda and Sebastian Padó

A b h i j e e t G u p t a &

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Interest in Distributional Semantics (etc.)

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Interest in Distributional Semantics (etc.)

  • Relation to formal semantics;
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Interest in Distributional Semantics (etc.)

  • Relation to formal semantics;
  • Relevance to experimental linguistics;
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Interest in Distributional Semantics (etc.)

  • Relation to formal semantics;
  • Relevance to experimental linguistics;
  • Relation between language and the world.
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Interest in Distributional Semantics (etc.)

  • Relation to formal semantics;
  • Relevance to experimental linguistics;
  • Relation between language and the world.
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Language and the world

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Language and the world

… that dog ate my shoe …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Language and the world

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Distributional Semantics (DS)

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Distributional Semantics (DS)

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

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Distributional Semantics (DS)

… that dog ate my shoe … … a young dog is called a puppy … … every cat ate too much … … when my cat was young she …

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

But what sort of concepts does DS model?

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

But what sort of concepts does DS model?

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

But what sort of concepts does DS model?

dog cat

house flat

animal red

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

But what sort of concepts does DS model?

dog cat

house flat

animal red

“cat”

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Westera & Boleda (2019, IWCS):

Distributional Semantics as a model of concepts?

  • The vectors of DS are abstractions over
  • ccurrences.
  • And so are concepts (e.g., Piaget).

But what sort of concepts does DS model?

dog cat

house flat

animal red

“cat”

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Westera & Boleda (2019, IWCS):

Should Distributional Semantics account for entailment?

“cat”

“cat”

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Westera & Boleda (2019, IWCS):

Should Distributional Semantics account for entailment?

“cat”

“cat”

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Westera & Boleda (2019, IWCS):

Should Distributional Semantics account for entailment?

“cat”

“animal” “cat”

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Westera & Boleda (2019, IWCS):

Should Distributional Semantics account for entailment?

“cat”

“animal” “cat”

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Westera & Boleda (2019, IWCS):

Should Distributional Semantics account for entailment?

“cat”

“animal” “cat”

No .

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“cat”

“animal” “cat”

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Language and the world are not perfectly aligned

“cat”

“animal” “cat”

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Language and the world are not perfectly aligned

“cat”

“animal” “cat”

~ ~

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Language and the world are not perfectly aligned

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Language and the world are not perfectly aligned

  • This is not (just) a technical challenge, but interesting.
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Language and the world are not perfectly aligned

  • This is not (just) a technical challenge, but interesting.
  • Are some parts of language closer to the world than other parts?

Does this show in DS? Can we exploit this?

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Language and the world are not perfectly aligned

  • This is not (just) a technical challenge, but interesting.
  • Are some parts of language closer to the world than other parts?

Does this show in DS? Can we exploit this?

S

  • me

e x p r e s s i

  • n

s a r e u s e d mo r e r i g i d l y t h a n

  • t

h e r s

. .

.

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Language and the world are not perfectly aligned

  • This is not (just) a technical challenge, but interesting.
  • Are some parts of language closer to the world than other parts?

Does this show in DS? Can we exploit this?

S

  • me

e x p r e s s i

  • n

s a r e u s e d mo r e r i g i d l y t h a n

  • t

h e r s

. .

. ( K r i p k e , ‘ 8 )

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Approach

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Approach

  • Let’s compare two kinds of representations of category concepts:
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Approach

  • Let’s compare two kinds of representations of category concepts:

– Predicate-based:

Word vector of a predicate that is used to denote the category.

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Approach

  • Let’s compare two kinds of representations of category concepts:

– Predicate-based:

Word vector of a predicate that is used to denote the category.

– Name-based:

Centroid of the word vectors of names of instances of the category.

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Approach

  • Let’s compare two kinds of representations of category concepts:

– Predicate-based:

Word vector of a predicate that is used to denote the category.

– Name-based:

Centroid of the word vectors of names of instances of the category.

E . g . , f

  • r

S c i e n t i s t , t h e w

  • r

d v e c t

  • r
  • f

“ s c i e n t i s t ”

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Approach

  • Let’s compare two kinds of representations of category concepts:

– Predicate-based:

Word vector of a predicate that is used to denote the category.

– Name-based:

Centroid of the word vectors of names of instances of the category.

E . g . , f

  • r

S c i e n t i s t , t h e w

  • r

d v e c t

  • r
  • f

“ s c i e n t i s t ”

E . g . , t h e me a n

  • f

v e c t

  • r

s f

  • r

“ A l b e r t E i n s t e i n ” , “ E mmy No e t h e r ” , …

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Approach

  • Let’s compare two kinds of representations of category concepts:

– Predicate-based:

Word vector of a predicate that is used to denote the category.

– Name-based:

Centroid of the word vectors of names of instances of the category.

  • Evaluation against human judgments of category relatedness.

E . g . , f

  • r

S c i e n t i s t , t h e w

  • r

d v e c t

  • r
  • f

“ s c i e n t i s t ”

E . g . , t h e me a n

  • f

v e c t

  • r

s f

  • r

“ A l b e r t E i n s t e i n ” , “ E mmy No e t h e r ” , …

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Representing a concept by the distribution of names of its instances

Matthijs Westera, Gemma Boleda and Sebastian Padó

A b h i j e e t G u p t a &

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Existing data/model we use

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Existing data/model we use

  • The Instantiation dataset (Boleda, Gupta, and Padó, 2017, EACL):

– e.g., <Emmy Noether, scientist>, <Edinburgh, capital>

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Existing data/model we use

  • The Instantiation dataset (Boleda, Gupta, and Padó, 2017, EACL):

– e.g., <Emmy Noether, scientist>, <Edinburgh, capital> – derived from WordNet’s ‘instance hyponym’ relation.

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Existing data/model we use

  • The Instantiation dataset (Boleda, Gupta, and Padó, 2017, EACL):

– e.g., <Emmy Noether, scientist>, <Edinburgh, capital> – derived from WordNet’s ‘instance hyponym’ relation.

  • We focus on the 159 categories that have at least 5 entities.
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Existing data/model we use

  • The Instantiation dataset (Boleda, Gupta, and Padó, 2017, EACL):

– e.g., <Emmy Noether, scientist>, <Edinburgh, capital> – derived from WordNet’s ‘instance hyponym’ relation.

  • We focus on the 159 categories that have at least 5 entities.
  • As DS representations of the entities’ names and categories’

predicates we use the Google News embeddings (Mikolov, Sutskever,

et al., 2013, ANIPS).

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Evaluation: gathering human judgments

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Evaluation: gathering human judgments

Following Bruni, Tran and Baroni’s MEN benchmark (2012, JAIR):

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Evaluation: gathering human judgments

Following Bruni, Tran and Baroni’s MEN benchmark (2012, JAIR):

  • We semi-randomly sampled 1000 category pairs (out of 12.5K).
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Evaluation: gathering human judgments

Following Bruni, Tran and Baroni’s MEN benchmark (2012, JAIR):

  • We semi-randomly sampled 1000 category pairs (out of 12.5K).
  • ‘Comparative’ task: which pair of categories are more related

to each other?

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Evaluation: gathering human judgments

Following Bruni, Tran and Baroni’s MEN benchmark (2012, JAIR):

  • We semi-randomly sampled 1000 category pairs (out of 12.5K).
  • ‘Comparative’ task: which pair of categories are more related

to each other?

  • Also same way of computing aggregated ‘relatedness’ scores.
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Crowdsource task

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Main result

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Main result

  • Spearman (ranking) correlations between:
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Main result

  • Spearman (ranking) correlations between:

– cosine similarities from Name-based / Predicate-based

and

– aggregate scores from our human judgments

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Main result

  • Spearman (ranking) correlations between:

– cosine similarities from Name-based / Predicate-based

and

– aggregate scores from our human judgments

  • Result:

– Predicate-based: 0.56

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Main result

  • Spearman (ranking) correlations between:

– cosine similarities from Name-based / Predicate-based

and

– aggregate scores from our human judgments

  • Result:

– Predicate-based: 0.56 – Name-based: 0.74

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Artist’s impression

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Artist’s impression

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How many names do we need?

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How many names do we need?

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How many names do we need?

S u r p r i s i n g l y f e w !

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Entities need to be representative

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Entities need to be representative

  • E.g., the Name-based model overestimates surgeon ~ siege...
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Entities need to be representative

  • E.g., the Name-based model overestimates surgeon ~ siege...
  • Instances of surgeon in the Instantiation dataset:

– William Cowper – James Parkinson – Alexis Carrel – Walter Reed – William Beaumont – Joseph Lister

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Entities need to be representative

  • E.g., the Name-based model overestimates surgeon ~ siege...
  • Instances of surgeon in the Instantiation dataset:

– William Cowper – James Parkinson – Alexis Carrel – Walter Reed – William Beaumont – Joseph Lister

I n v

  • l

v e d i n WW1

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Entities need to be representative

  • E.g., the Name-based model overestimates surgeon ~ siege...
  • Instances of surgeon in the Instantiation dataset:

– William Cowper – James Parkinson – Alexis Carrel – Walter Reed – William Beaumont – Joseph Lister

I n v

  • l

v e d i n WW1 M e mb e r s

  • f

U S mi l i t a r y c

  • r

p s

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Entities need to be representative

  • E.g., the Name-based model overestimates surgeon ~ siege...
  • Instances of surgeon in the Instantiation dataset:

– William Cowper – James Parkinson – Alexis Carrel – Walter Reed – William Beaumont – Joseph Lister

Wr

  • t

e “ t h e s i e g e

  • f

c h e s t e r ” ( ? ) I n v

  • l

v e d i n WW1 M e mb e r s

  • f

U S mi l i t a r y c

  • r

p s

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Discussion

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Discussion

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Discussion

  • Main finding:
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Discussion

  • Main finding:

– Name-based representations of category concepts align better

with ‘the world’ than Predicate-based representations.

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Discussion

  • Main finding:

– Name-based representations of category concepts align better

with ‘the world’ than Predicate-based representations.

– Even a small number of (representative) names can be enough.

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Discussion

  • Main finding:

– Name-based representations of category concepts align better

with ‘the world’ than Predicate-based representations.

– Even a small number of (representative) names can be enough.

  • Outlook:

– Not every category has named instances...

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Discussion

  • Main finding:

– Name-based representations of category concepts align better

with ‘the world’ than Predicate-based representations.

– Even a small number of (representative) names can be enough.

  • Outlook:

– Not every category has named instances... – NLP relevance? Vs. sense disambiguation? Contextualized word

embeddings (ELMo, BERT, …)?

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Discussion

  • Main finding:

– Name-based representations of category concepts align better

with ‘the world’ than Predicate-based representations.

– Even a small number of (representative) names can be enough.

  • Outlook:

– Not every category has named instances... – NLP relevance? Vs. sense disambiguation? Contextualized word

embeddings (ELMo, BERT, …)?

– Cognitive relevance? E.g., prototype theory?

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Acknowledgments

This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 715154). This paper reflects the authors’ view only, and the EU is not responsible for any use that may be made of the information it contains.

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Image sources

https://ui-ex.com/explore/whale-transparent-dark/ https://commons.wikimedia.org/wiki/File:Cowicon.svg https://commons.wikimedia.org/wiki/File:Bird_1010720_drawing.svg https://commons.wikimedia.org/wiki/File:Dog_silhouette.svg https://commons.wikimedia.org/wiki/File:Cat_silhouette_darkgray.svg https://commons.wikimedia.org/wiki/File:Frog_(example).svg https://commons.wikimedia.org/wiki/File:PeregrineFalconSilhouettes.svg https://commons.wikimedia.org/wiki/File:Common_goldfish_silhouette.svg https://commons.wikimedia.org/wiki/File:Six_weeks_old_cat_(aka).jpg https://nl.m.wikipedia.org/wiki/Bestand:Kooikerhondje_puppy.jpg https://nl.m.wikipedia.org/wiki/Bestand:Golden_Retriever_eating_crust_of_pizza.jpg https://commons.wikimedia.org/wiki/File:Cat-eating-prey.jpg

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Where are predicates and names, anyway?

predicate name

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Where are predicates and names, anyway?

predicate name

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Crowdsource task

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Crowdsource task

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Crowdsource task instructions

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Crowdsource task instructions

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Why definitions?

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Why definitions?

  • The same words can often be used to denote various categories.
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Why definitions?

  • The same words can often be used to denote various categories.
  • To properly evaluate the Name-based approach, the human

judgments should be about the categories as intended by the Instantiation dataset we use.

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Why definitions?

  • The same words can often be used to denote various categories.
  • To properly evaluate the Name-based approach, the human

judgments should be about the categories as intended by the Instantiation dataset we use.

  • (Would be good practice more generally – e.g., vs. the good

subject effect.)

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Why definitions?

  • The same words can often be used to denote various categories.
  • To properly evaluate the Name-based approach, the human

judgments should be about the categories as intended by the Instantiation dataset we use.

  • (Would be good practice more generally – e.g., vs. the good

subject effect.)

  • This may give the Predicate-based approach a disadvantage…
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98

Why definitions?

  • The same words can often be used to denote various categories.
  • To properly evaluate the Name-based approach, the human

judgments should be about the categories as intended by the Instantiation dataset we use.

  • (Would be good practice more generally – e.g., vs. the good

subject effect.)

  • This may give the Predicate-based approach a disadvantage…

– but this disadvantage is not an unfair one.

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A closer look per ontological domain

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A closer look per ontological domain Predicate

  • based:
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A closer look per ontological domain Predicate

  • based:
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A closer look per ontological domain Predicate

  • based:

Name- based:

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A closer look per ontological domain Predicate

  • based:

Name- based:

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Non-representative instances of ‘object’ categories

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A closer look per ontological domain Predicate

  • based:

Name- based:

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A closer look per ontological domain Predicate

  • based:

Name- based:

.54 .64