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Using Wikipedia categories for research Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia

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Page 1: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Using Wikipedia categories for research

Opportunities, Challenges, and Solutions

Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia

Page 2: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Hierarchical organization of concepts

Page 3: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Taxonomies are useful in many different domains:

Image classification

Medical domain

Q&A bots

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Page 4: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

is-a(Mammals, Animals)

is-a(Felines, Mammals)

is-a(Felines, Animal)

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Statement: Animals must eat to live

Question: Does Garfield eat? Yes

An automated reasoning tool can infer new knowledge

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Page 5: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

… and in sections recommendation!

Given an article A in language L, recommend the list of sections to be added to the article considering similar articles to article A in language L.

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* Leila’s talk -- Showcase Dec 2017

Page 6: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Generating concept-based templates

An article about a person can be represented with:

● Early life● Personal life● Death

The structure shared between multiple children

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Page 7: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Generating the complete taxonomy manually is not feasible!

288 languageshundreds of thousands concepts

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Page 8: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Wikipedia has a category network!

Page 9: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Page 10: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Potential hyponym of French artists

Potential hypernym of French artists

Page 11: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Wait, it’s not so easy…

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Page 12: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

The category network has loops!

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Government ➜ Public administration ➜ Public economics ➜ Economic policy ➜ Government

A fast and effective heuristic for the feedback arc set problem

Peter Eades, Xuemin Lin, W.F. Smyth

Page 13: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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is-a(French artists, French art)

Multiple entities don’t respect the is-a relation

Page 14: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Related work

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MultiWiBiMultiWiBi: The multilingual Wikipedia bitaxonomy project.

Tiziano Flati, Daniele Vannella, Tommaso Pasini, Roberto Navigli.

Head Taxonomy Revisiting Taxonomy Induction over Wikipedia

Amit Gupta, Francesco Piccinno, Mikhail Kozhevnikov, Marius Pasca, Daniele Pighin

Generated with language-based heuristics

Page 15: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Goal:

Generate a set for sections to recommend based on the categories of the article

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We need to preserve as much as possible the original topology and remove what could add

“noise”

Page 16: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Our method!

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Page 17: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Assuming we have a generic high-level type for each article in Wikipedia

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Taxonomic categories should contain articles of the same type!

Page 18: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

DBpedia - Types extraction

55 top-level types

Page 19: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

The concept of purity

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Pure categoryThe distribution of types is

homogeneous

Non-pure categoryThe distribution of types is

heterogeneous

Scientists → “Person” Football → “Person”, “Event”, “Organization”

Page 20: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Idea:

With a bottom-up approach, we can remove the categories where different types converge

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Non-pure

Pure

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Page 23: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Page 24: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Page 25: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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Page 26: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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The category is marked as not-pure

Page 27: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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In the real world we don’t have perfect pure

categories!

Pure categories have a high unbalanced types distribution

Page 28: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Gini coefficient

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Page 29: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

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How can we select a Gini good threshold?

We manually annotated ~700 is-a (transitive)

is-a(British scientist, People)

is-a(Gaelic games grounds, Football)

We can prune the network with different thresholds

Page 30: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Conclusion

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We presented a language-independent framework to clean the category network

Customizations:

Types from Wikidata, DBPedia, etc

Dynamic threshold for the Gini coefficient

Gini coefficient selection

Deletion of edges vs. nodes

Page 31: Opportunities, Challenges, and Solutions Using Wikipedia … · Opportunities, Challenges, and Solutions Tiziano Piccardi, Michele Catasta, Robert West, Leila Zia. 2 Hierarchical

Read more about sections recommendation:

https://meta.wikimedia.org/wiki/

Research:Expanding_Wikipedia_articles_across_languages

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