hide the stack:toward usable linked data
DESCRIPTION
The explosion in growth of the Web of Linked Data has provided, for the first time, a plethora of information in disparate locations, yet bound together by machine-readable, semantically typed relations. Utilisation of the Web of Data has been, until now, restricted to the members of the community, eating their own dogfood, so to speak. To the regular web user browsing Facebook and watching YouTube, this utility is yet to be realised. The primary factor inhibiting uptake is the usability of the Web of Data, where users are required to have prior knowledge of elements from the Semantic Web technology stack. Our solution to this problem is to hide the stack, allowing end users to browse the Web of Data, explore the information it contains, discover knowledge, and use Linked Data. We propose a template-based visualisation approach where information attributed to a given resource is rendered according to the rdf:type of the instance.TRANSCRIPT
HidetheStack:TowardUsableLinkedData
A.‐S.Dadzie1,M.Rowe2&D.Petrelli3
1.TheOAKGroup,Dept.ofComputerScience,TheUniversityofSheffield
2.TheKnowledgeMediaInsPtute,TheOpenUniversity3.Art&DesignResearchCentre,SheffieldHallamUniversity
KeyMessage• LinkedData
– connecPonsbetweendisparate,independent(albeitrelated)data– renderingpublicinterestdataaccessible
• allowinghiddeninformaPontobediscoveredmoreeasily
• enablingquesPonstobeansweredmorefully
• PotenPalwidelyrecognised,but– verylarge‐scale,wide‐coverage,highlyinter‐linkeddatarepositories– under‐uPlisedoutsideSemanPcWebcommunity
• Aimsoftheresearch– explorenewmethodsforpresenPngLinkedDatatowideraudience
– supportmoreintuiPveexploraPonandknowledgeretrieval– encouragewiderusebyweb‐savvybutnon‐technicalusers
Outline
• Challenges
• IllustraPveScenario
• ExisPngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
Outline
• Challenges
• IllustraPveScenario
• ExisPngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
ChallengesinLinkedDataConsumpPon
1. CombaPnginformaPonoverload2. ExploraPonstarPngpoint3. Returningsomethinguseful
4. EnablinginteracPon
HowcanwemakeLinkedDatausabletoreal,endusers?
• whereendusersbroadlyclassifiedintooneof:– SemanPcWebexperts
– web‐savvybutnon‐technical
Outline
• Challenges
• Illustra.veScenario
• ExisPngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
Sampledataset‐Data.dcs• researchgroupsinDCS,UniversityofSheffield• ontologies(re)used
– FOAF,PRV,SWRC,BIB• byLinkedDatastandardsverysmall
– over8000statements– ~3000(disPnct)graphnodes– howeversPllhighlightsthescaleofthechallengesfaced
Scenario
• InformaPon‐seekingscenario
– enduser:aprimaryschoolteacher
– task:lookingforresearchinlocaluniversityon‘WebTechnology’
– toolstypicallyusedforinformaPonseekingacPviPes:• websearch/browse• library
• considertheuniversitydepartment’swebsitebuiltontopofData.dcs
Outline
• Challenges
• IllustraPveScenario
• Exis.ngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
ToolsforconsumingLinkedData
• SemanPcWebuser– wellcateredfor– typicaltasks
• browsingRDF• validaPngdataandmodels
• extracPngdatausingformalquerysyntax
• mainstreamwebuser– lowertoolsupport– typicaltasks‐exploratoryinformaPonseeking
• searchandquery(usinglessformalmethods,e.g.,forms)
• browsingtodiscoverinformaPon
• sharingofinformaPondiscovered,resultsofanyanalysis
ToolsforconsumingLinkedDataToolType ExamplesofTools
formadedtextdisplayofRDF(e.g.,usingHTMLtables,templates)
Sig.ma,Marbles,URIBurner,Haystack,Tabulator
RDFgraphmodel W3CRDFValidator,SindiceInspector
othergraphvisualisaPon IsaViz,RDFGravity,Cytoscape,RelFinder
otherdomain‐specificvisualisaPon DBPediaMobile,TalisResearchFundingExplorer
ExpectedSkillSet ExamplesofTools
understandingofSWtechnologystack
Sig.ma,Marbles,URIBurner,W3CRDFValidator,RelFinder,Tabulator
formalquerying,e.g.,SPARQL LESS
basictoadvancedknowledgeseeking,exploratorynavigaPon
DBPediaMobile,RelFinder,TalisRFE,IsaViz
webbrowsing(desktop,mobile) LESS,DBPediaMobile
See also: • Dadzie, A.-S. & Rowe, M. (In press). Approaches to Visualising Linked Data: A Survey, the Semantic Web Journal — Special Call for Survey articles on Semantic Web topics. • Katifori, A., Halatsis, C., Lepouras, G., Vassilakis, C. & Giannopoulou, E. (2007). Ontology visualization methods — a survey, ACM Computing Surveys.
Outline
• Challenges
• IllustraPveScenario
• ExisPngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
ATemplate‐basedSoluPon
• takingadvantageofself‐describingRDFdata– lookupclassofagivenresource– loadtemplatebasedonclass–i.e.,rdf:typeoftheinstance
• focusonperPnentinformaPoninadataset
• highlightrelaPonshipswithindata• allowenduserstoretrievedetailinROIs(regionsofinterest)
• combinetemplateswithinformaPon/knowledgevisualisaPon
– hidethecomplexityoftheunderlyingdata– removetheneedforspecialistSWknowledgeorskill
Whythisapproach?• Templates
– valueseeninthewideuseofFresnellensesandothertemplatedevelopmenttoolsandlanguages,e.g.,IsaViz,LENA,LESS
– simplicity,reusability,extensibility,flexibility
• VisualisaPon– overviewtosupportdetecPonofdatastructure
• exploratoryinformaPonseeking
• idenPfying/highlighPngrelaPonships• recognisinganomalies,errors
– reducPonincogniPveload–throughadvancedhumanpercepPon• especiallyusefulforanalysisoflarge,complexdata
TemplateDesign
• idenPfykeyconcepts&relevantmetadatatodefinetemplates– matchtostandardontologies,e.g.,FOAF,PRV,SWRC,BIB
– SPARQLqueries–builtbasedonFresnellensSPARQLselectors
• presentaPonmethods– visualoverview‐node‐linkgraph
• collapseinformaPonrelatedtokeyconceptsintocompoundnodes
• filteroutlessimmediatelyrelevantdata–providemoreroomforROIs
– visualencoding• colourcodingbasedonRDFtype(nodesandlinks)• iconsbasedonRDFtype(nodes)• sizetoencodenodeproperPes,e.g.,no.ofoutlinks
– detailview• textandthumbnails/icons
Data.dcstemplates
• mainconcepts– Organisa.on[<http://xmlns.com/foaf/0.1/Group>]
– Person [<http://xmlns.com/foaf/0.1/Person>]
– Publica.on [<http://zeitkunst.org/bibtex/0.1/bibtex.owl#Entry>]
• informaPonofmaininterest–keyconcepts– organisaPonalstructure‐researchgroups– people– relaPonshipswithinstructure
Challenge1:Comba.nginforma.onoverload
• verylargeamountsofdistributed,heterogeneousdata
• highinter‐linking
Data.dcs–RDFgraph
DrawnusingSindiceInspector–first1000triplesonlyforusabilityreasons
Data.dcs‐RDFTextvsBasicGraph
Data.dcs–TemplateGraphView
Challenge1:SoluPonProposed
• Comba.nginforma.onoverload– verylargeamountsofdistributed,heterogeneousdata
– highinter‐linking
• oursoluPon:– visualoverview+filters– highlighPngkeyrelaPonships– detailview
• focusongraphROIwithincontextofsurroundingdata+textdetail&thumbnailsorrepresentaPveicons
• SWusers– mayhaveaspecificURItoexplore
• mainstreamusers– mayormaynothaveaspecificstarPngpoint
– onenstartwithavagueideaandbrowsetofindifthereisanythinginteresPng
Challenge2:Explora.onstar.ngpoint
Designideas:Detailtemplates
Challenge2:SoluPonproposed
• Explora.onstar.ngpoint– SWusers
• mayhaveaspecificURItoexplore
– mainstreamusers• mayormaynothaveaspecificstarPngpoint
• onenstartwithavagueideaandbrowsetofindwhattheywant
• oursoluPon:– supportboth
• whereinput,specificURIasfocusatstart• extractlistofpotenPalstartpoints
– selectedfromkeyRDFtypesinadataset
– randomlychosenfocus–influencedbycontext
• centregraphonfocus
• whatistheenduserlookingfor?
• howcanwepresentthedatasotheyareabletofindit?
Challenge3:Returningsomethinguseful
Data.dcs–RDF/XML
Co‐ordinatedTemplateViews
Co‐ordinatedTemplateViews
UndertheHood‐DetailView
• e.g.,SPARQLquerytemplateforthefullpublicaPonview
PREFIX foaf: <http://xmlns.com/foaf/0.1/> PREFIX bib: <http://zeitkunst.org/bibtex/0.1/bibtex.owl#>
SELECT DISTINCT ?publicationTitle ?year ?bookTitle ?personUri ?author ?imageUri
WHERE { <data.dcs:publicationUri> bib:title ?publicationTitle ; bib:hasYear ?year ;
bib:hasBookTitle ?bookTitle ; foaf:maker ?personUri . ?personUri foaf:name ?author ; foaf:img ?imageUri } ORDER BY DESC(?year) ?publicationTitle
• Returningsomethinguseful– whatistheenduserlookingfor?– howcanwepresentthedatasotheyareabletofindit?
• OursoluPon– graphoverview+detailtemplateview
– reusefamiliarwebbrowserlookandfeel(detail)
– interacPvegraph• tosupportexploratorynavigaPon• retaincontextofsurroundinginformaPon
• colourcodingtohighlightkeyresourcetypesandrelaPonships
Challenge3:SoluPon
• OursoluPon– graphoverview+detailtemplateview
– reusefamiliarwebbrowsinginteracPon
– clicktonavigatethroughdata(inbothviews)– pan+zoomforgraphview
– filterstoremovelessrelevantinformaPon
Challenge4:Enablinginterac.on
Outline
• Challenges
• IllustraPveScenario
• ExisPngWork• Approach
• Ini.alEvalua.on• Conclusions&NextSteps
• Acknowledgements
FormaPveEvaluaPon• atESWC2010‘EssenPalHCIfortheSemanPcWeb’tutorial
– focusgroupof(14)“expertreviewers”– assessingusabilityforbothmainstreamandexpertusers
– trainingtaskandaninformaPonexploraPonexercise
• graphsfoundtobeexpressive• graphvieweffecPveingivingasenseofdatadistribuPon
• detailvieweffecPvelydisplayedkeyresources“inaneatandconciseway”
• prototypeseentohavepotenPalforexploringanddebuggingLD
• somedifficultyforusersnotfamiliarwithinteracPvegraphlayout– “eventuallyyougotabigpictureofthedata’’– “IlikedthedirectmanipulaPonbutthegraphshouldstayput
[whenIclick]”
Outline
• Challenges
• IllustraPveScenario
• ExisPngWork• Approach
• IniPalEvaluaPon• Conclusions&NextSteps
• Acknowledgements
Conclusions
• exploredhuman‐centredsoluPonforconsumingLinkedData– exploiPngtemplates(viaSWtechnology)– combinedwithvisualisaPon
• evaluaPonhighlightedchallengessPllremaining‐amongothers:– scale– complexity
• however–promisingstart....• NextSteps
– moreusercontrol‐(intuiPve)supportfordefiningtemplates,filters– dynamicupdatewithnewLinkedData– formalusabilityevaluaPonwithwiderrangeofusers
Outline
• Challenges• IllustraPveScenario
• ExisPngWork
• Approach• IniPalEvaluaPon
• Conclusions&NextSteps
• Acknowledgements– parPcipantsofESWC2010‘EssenPalHCIfortheSemanPcWeb’tutorial– Funding
• A‐SDadzie–SmartProducts&WeKnowIt(EUFP7),X‐Media(EUFP6)
• MRowe–WeGov(EUFP7)
• DPetrelli–X‐Media(EUFP6)
HidetheStack@SWDogfood