Folksonomies and tagging: New developments in social bookmarking
Tech4Ontologies and Folksonomies
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Transcript of Tech4Ontologies and Folksonomies
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8/14/2019 Tech4Ontologies and Folksonomies
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OntologiesandFolksonomies
SocialComputingClass2009
u ta ass eva
UniversityofSaskatchewan
SOFIA: http://picasaweb.google.ca/julitav/DropBox?authkey=Gv1sRgCK-3v5mB5a38Dg#5399921463445091762
HowtoorganizetheWebsothat
wecanfindstuff?
TheSemanticWeb:(T. Berners-Lee et al., 2001)... is an extension of the current web in which information is iven well-defined...
meaning, better enabling computers and people to work in co-operation.
RuleInterchang
Query language for RDF Format
Metadata: syntax
Metadata: semantics
Things/objects
Ontology:
Defines thvocabular
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Approachestoorganizeknowledge
ThePhilosophical/ArtificialIntelligenceapproach Ontologies (fromWikipedia): Ontology (fromthe Greek ,genitive : ofbeing (neuterparticiple
of: tobe)and , logia: science, study, theory)isthephilosophical studyofthenatureofbeing, existence or reality ingeneral,as
wellasofthebasic categoriesofbeing andtheirrelations.
In computerscience and informationscience,an ontology isaformal
representationofasetofconceptswithinadomain andtherelationships
betweenthoseconcepts.Itisusedto reason aboutthepropertiesofthat
domain,andmaybeusedtodefinethedomain.Anontologyisa"formal,
explicitspecificationofasharedconceptualization".[1] Anontologyprovidesa
sharedvocabulary,whichcanbeusedtomodeladomain
TheSocialWebapproach
TagsandFolksonomies
Ontologies
TaxonomiesLa ers la ers la ersofmetadataVariousmetadatastandards
WordNet
LetsplayastandardsAcronymtrivia:
XCBF,XKMS,SAML,XACML,WSML
,Sincethemid1970s,researchersinthefieldofartificialintelligence haverecognizedthatcapturingknowledgeisthekeytobuildinglargeandpowerfulAIsystems.AIresearchersarguedthattheycouldcreatenewontologiesas computationalmodels thatenablecertainkindsofautomatedreasoning.
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Metadata
HTML provides formatting
Social Com utin
RDF provides metadata about web resources
Teacher Name
Student Name
XML provides syntax
6086758
RDF Schema adds vocabulary for RDF.
Organizes the vocabulary in typed hierarchySocial Computing
Teacher Name
Student Name
- Class, subClassOf, type
- Property, subPropertyOf- Domain, range
RDF(resourcedescriptionframework)RDF is based on the idea of identifying things using Web identifiers(called Uniform Resource Identifiers, or URIs), and describing resources in terms of
simple properties and property values.
Eric Miller
Dr.
RDF Identifies:
individuals e Eric M iller, . ., ,
identified by http://www.w3.org/People/EM/contact#mekinds of things, e.g., Person,identified by http://www.w3.org/2000/10/swap/pim/contact#Person
properties of those things, e.g., mailbox,identified by http://www.w3.org/2000/10/swap/pim/contact#mailbox
values of those properties, e.g. mailto:[email protected] as the value of the mailbox property
RDF Tutorial (30 min)
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Ontologies
OntologycomponentsandlanguagesCommon components of ontologies include (Wikipedia)
" "
Classes: sets, collections, concepts, types of objects, or kinds of things.[10]
Attributes: aspects, properties, features, characteristics, or parameters that objects
(and classes) can haveRelations: ways in which classes and individuals can be related to one another
Function terms: complex structures formed from certain relations that can be used
in place of an individual term in a statementRestrictions: formally stated descriptions of what must be true in order for some
assertion to be accepted as input
Rules: statements in the form of an if-then (antecedent-consequent) sentence thatdescribe the logical inferences that can be drawn from an assertion in a particular
formAxioms: assertions (including rules) in a logical form that together comprise the
overall theory that the ontology describes in its domain of application.Events: the changing of attributes or relations
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Ontologylanguages
An ontology language is a formal language used to encode the ontology.
IDEF5 is a software engineering method to develop and maintain usable,
accurate, domain ontologies.
KIF is a syntax for first-order logic that is based on S-expressions.
Rule Interchange Format (RIF) and F-Logic combine ontologies and rules.
OWL is a language for making ontological statements, developed as a
follow-on from RDF and RDFS, as well as earlier ontology language
projects including OIL, DAMLand DAML+OIL. OWL is intended to be used, ,
individuals) are defined as RDF resources, and identified by URIs.
Example:FOAFontologyforsocial
relationships
http://www.foafproject.org/ C asses:
| Agent | Document | Group | Image | OnlineAccount | OnlineChatAccou
nt | OnlineEcommerceAccount |OnlineGamingAccount | Organization | P
erson | PersonalProfileDocument | Project |
Properties:
| accountName | accountServiceHomepage| aimChatID | based_near | b
irthday | currentProject | depiction | depicts| dnaChecksum | family_nam
t | homepage | icqChatID |img | interest | isPrimaryTopicOf | jabberID | k
nows | logo | made | maker | mbox | mbox_sha1sum | member | memb
ershipClass| msnChatID | myersBriggs | name | nick | openid | page | pas
tProject | phone | plan | primaryTopic | publications |schoolHomepage |
sha1 | surname | theme | thumbnail | tipjar | title | topic | topic_interest
| weblog | workInfoHomepage |workplaceHomepage | yahooChatID |
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Attemptstoharvestontologypower
OntologySearchengineSwoogle:http://swoogle.umbc.eduhttp://ebiquity.umbc.edu/project/html/id/53/ (description)
Butitworksonlyforsemanticallyannotatedsites Humansannotatingcontent currentlythemost
commonapproach
Buthowtoannotatedynamicservicecontentefficiently?
,constructingdeepdatasignaturefordocsand
services,thenfrequencydistributionanalysesandclusteringactiveareaofresearch
HowdoYOUorganize
Yourkitchencupboards?
Yourclothesinthecloset?
Thefilesonyourcomputer?
Yourdigitalphotos?
The solution to overabundance of data is more data
David Weinberger
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Principlelimitationsofontologies
Anontologyalwaysreflectsaparticular,
E.g.librarycataloguesoptimizebookshelves physicallocationofbooksinlibrary(onebookinjustonecategory)
worldviewatthetimeofcataloguing Dewey, 200: Religion210 Natural theology220 Bible230 Christian theology240 Christian moral & devotional theology
250 Christian orders & local church260 Christian social theology270 Christian church histor
A: Marxism-LeninismA1: Classic works of Marxism-LeninismA3: Life and work of C.Marx, F.Engels, V.I.LeninA5: Marxism-Leninism PhilosophyA6: Marxist-Leninist Political Economics
280 Christian sects & denominations290 Other religions
DK: Former Soviet UnionDL: ScandinaviaDP: Iberian PeninsulaDQ: SwitzerlandDR: Balkan PeninsulaDS: AsiaDT: AfricaDU: OceaniaDX: Gypsies
A7/8: Scientific Communism
D: History (general)DA: Great BritainDB: AustriaDC: FranceDD: GermanyDE: MediterraneanDF: GreeceDG: ItalyDH: Low CountriesDJ: Netherlands
Hierarchiesandnonhierarchies
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Example Yahoo
Moreproblems Categorizinghasaspectsof
Mindreading(guessinghowotherswillinterpret)
Categorizingleadstoinformationloss
E.g.categoryofinterest:movies,films,cinema aretheyallthesamereally?
Smartpeoplethinkdifferently
Differentcommunitieshaveimplicitnamingagreements:hardtofindconsensus
Hardtoagreeuponthesemanticsofrelationships Evenifpeopleagreeformally,theymaystillinterpret
differently
Evensimplehierarchiesarehardtouse
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Useoftaxonomybasedannotation
17
Howtoimposeanontologyfordiverseandautonomoususers?
OnlythesimplestofthesimplehasachanceButatthatlevelofsimplicity,isitstilluseful?
SummaryWhendoesOntologicalClassificationworkwell?
Smallcor us
FormalcategoriesStableentitiesRestrictedentitiesClearedges
WhendoesOntologicalClassificationNOTworkwell?
Authoritative source of judgment
Coordinated users
Expert users
LargecorpusNoformalcategoriesUnstableentitiesUnrestrictedentitiesNoclearedges
Uncoordinated usersAmateur users
Naive catalogersNo Authority
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Folksonomies
19KeynoteITS'2008
Folksonomies(web2.0)
PositivesSelfishusersta forthemselvesEasytoaddTagscanexpressdifferentsemanticdimensions:content,
context,pedagogical,learnertype,mediatype, >similartometadata
Nostandards(just helpinavoidingmisspellings)Tagsharingleadstosocialqualitycontrol
,Tagcloudgivesasummaryofdocument(browsing)Allowseasysearchbytag(insteadofformingqueries)
20KeynoteITS'2008
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Folksonomies problems:
Themachinedoesnotknowthesemanticsoft e ocumentw t out now ng owt etags
relatetoeachother(i.e.anontologyoftags)
Cantsayhowtwodocumentsarerelatedorwhytheyaresimilar(notqualitatively)
Hardtosequenceapresentationfromtagged
materials
Butforaoneshotretrievaltagsareokay.
21KeynoteITS'2008
DATAMININGOFUSERCONTENTONTOLOGY
Snaptogrid(Gruber)
Contributetags
Suggesttags
Tagging
Ontologies /Semantic web
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Featuresofthesesolutions
Usercentered respectusersautonomy
Easyfortheuser justlikeafolksonomy
TheAIhappensinthebackground,theuserisnotawareofit
Simplicityandeaseofusepreserved,a van ageso on o ogya e
http://www.bazaarblog.com/2007/10/28/everythingismiscellaneousastoldbyvideo/