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“Concepts are our building bricks”

Why we need thesauri

Leonard Will

L.Will@willpowerinfo.co.ukwww.willpowerinfo.co.uk

And God said, Let there be light: and there was light.And God saw the light, that it was good: and God divided the lightfrom the darkness.And God called the light Day, and the darkness he called Night.

And God said, Let the waters under the heaven be gatheredtogether unto one place, and let the dry land appear: and it was so.And God called the dry land Earth; and the gathering together ofthe waters called he Seas: and God saw that it was good.

And out of the ground the LORD God formed every beast of thefield, and every fowl of the air; and brought them unto Adam tosee what he would call them: and whatsoever Adam called everyliving creature, that was the name thereof.And Adam gave names to all cattle, and to the fowl of the air, andto every beast of the field

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What is a thesaurus?

A thesaurus does three things:● Defines concepts – implicitly or explicitly● Labels concepts – with preferred and alternative

terms● Links concepts – with hierarchical and associative

relationships

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“The fundamental element of the SKOS vocabulary is the concept.Concepts are the units of thought – ideas, meanings, or(categories of) objects and events – which underlie manyknowledge organization systems. As such, concepts exist in themind as abstract entities which are independent of the terms usedto label them.” – SKOS primer

“When one is discussing a concept, having a label to use to referto it facilitates discourse, and identifies it as a specific idea,

making the concept more mnemonic andusable.” – Wikibooks

Concepts are units of thoughtA thesaurus identifies concepts, then labels them with terms

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A dangerous chemical

dihydrogen monoxide(DHMO)

● Fatal if inhaled● A major constituent of acid rain● Leads to corrosion and oxidation of many metals● Found to be present in Thames Water’s network

Other names: oxidane, hydrogenhydroxide, hydric acid,hydrohydroxic acid, hydroxic acid,hydrol

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A dangerous chemical

dihydrogen monoxide(DHMO)

Other names: oxidane, hydrogen hydroxide, hydricacid, hydrohydroxic acid, hydroxic acid, hydrolClarification if we have anotherway to define and clarify the

concept:

I wish I could finda book aboutrailway engines

The reference interview – refining the question.– Can a computer system do this job?

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Did you mean . . . ?Google can correct spelling, but it doesn’t know that a railwayengine is called a locomotive.Wikipedia has a “disambiguation” page, which is a kind ofthesaurus, with definitions of each concept:

Engine- Heat engine- - Internal combustion engine- - - Diesel engine- - - Wankel engine- - - Pulse jet engine- - External combustion engine- - - Steam engine[RT] In rail transportLocomotive- Electric locomotive

A thesaurus suggests narrower and broader terms

Art and architecture thesaurus – extract

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A thesaurus can serve as:a gazetteer, for searching … or a map, for navigation

UK Data Service HASSET thesaurus graphical display

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Thesaurusstructures inecommerce

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Thesaurusstructures inecommerceHierarchies ofnarrower concepts

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Thesaurusstructures inecommerce

Arrays, with nodelabels showingcharacteristics ofdivision:cameras by brand,resolution, zoom

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Information resources with thesaurus interfaces

Drilling down to refine a query

EBSCO visual search using the Inspec thesaurus

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Thesauri

Ontologies Social tagging andfolksonomies

Taxonomies

Linked data

SKOS

Semanticweb

InteroperabilityDigital librariesMetadata

Informationarchitecture

Search userinterfacesFaceted &

exploratorysearch

Queryformulation& expansion

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Thesauri and the semantic webTo use linked data, we have to define concepts which can beshared or mapped (with various degrees of equivalence).

Metadata registries - lists of data fields or vocabularies topopulate them.

Dublin Core specifies vocabulary encoding schemes whichmay be used to populate its data elements, ideally as linked data.

These vocabularies should be structured as thesauri.

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Thesauri and the semantic web

Schema.org defines properties of resources, which need to bepopulated with agreed values. These can be taken from anauthoritative list – e.g. properties of artworks can come from theArt and architecture thesaurus, and be linked using AAT’s linkeddata URIs:

<span property="material" content="http://vocab.getty.edu/aat/300022443">Pencil</span>

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Thesauri

Ontologies Social tagging andfolksonomies

Taxonomies

Linked data

SKOS

Semanticweb

InteroperabilityDigital librariesMetadata

Informationarchitecture

Search userinterfacesFaceted &

exploratorysearch

Queryformulation& expansion

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Image creditsSlide 3: Little Fishermen for Christ http://littlefishermen4christ.com/profiles/blogs/the-truth-of-genesis-an-attack-against-christians-jews-part-3#.VOe7hSyyNqFSlide4: http://biblestudyoutlines.org/bible-study-lessons/old-testament-bible-study/genesis-1-bible-study/Slide 5: http://www.internetmonk.com/archive/imonk-on-interpreting-genesis-1This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License.Slide 11: Charles Sturt University. https://www.csu.edu.au/courses/information-and-library-studies