Publishing and Interacting with Linked Data
description
Transcript of Publishing and Interacting with Linked Data
Publishing and Interacting with Linked Data
Roberto Garcia, Josep Maria Brunetti, Antonio López-Muzás, Juan Manuel Gimeno, Rosa Gil
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
HCI & Data Integration Research GroupUniversitat de Lleida, Spain
Overview
• RhizomerPlatform for Linked Data publishing (also Semantic Data)–Data access
• Read (LinkedData / SPARQL) • Write (Semantic FORMS + HTTP PUT/POST/DEL)
–Data sources• Jena (File, MySQL, Postgres), Virtuoso, OWLIM,…
–Interaction• Overview: Navigation bars• Filter: Facets• Details: HTML+RDFa, Interaction Web Services
(map, timeline,…)
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Architecture
• Server part:– REST interface over repository
• GET: URI (LinkedData) or SPARQL Query• PUT/POST/DELETE: data management
MetadataStore
Rhizomer
GE
T
PU
T
PO
ST
DE
L
search new edit delete
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Architecture
• Scope of GET operations:– Concise Bounded Description (CBD) +
rdfs:labels for all selected resources
• Scope of POST/PUT/DEL operations:– Concise Bounded Description
• DESCRIBE queries by default– Facilitate browsing heterogeneous data– Without a priori knowledge
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
http://rhizomik.net/~rosa
http://...vcard#ADR
http://...vcard#StreetJaume II, 69
http://...vcard#Locality
Lleida
http://...onto#affiliation
http://www.udl.cat
http://...rdf#type
http://...rdfs#label
Rosa Gil
http://...rdf#type
http://...onto#Professor
http://...rdf#type
http://...vcard#work
http://...onto#University
Architecture
• DESCRIBE http://rhizomik.net/~rosa: CBD(…~rosa) = Fragment A U rdfs:labels
Fragment A
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Architecture
RDF2HTML
GET RDF2HTML
<s5t:Audio rdf:about="http://www.segre.com/audio/20070323-bm.mp3"> <dc:title>Butlletí Migdia</dc:title> <dc:date>2007-03-23</dc:date> <s5t:genre rdf:resource="&srs;11000000"/> <s5t:transcriptResource> http://www.segre.com/audio/20070323-bm.xml </s5t:transcriptResource></srt:Audio> http://www.segre.com/ audio/ 20070323-bm.mp3 a Audio
title Butlletí Migdia
date 2007-03-23
genre politics
transcript http://www.segre.com/audio/20070323-bm.xml
Referrers
http://rhizomik.net/.../NewsCodes-SubjectsOnto#11000000 a Subject
label politics
descriptionLocal, regional, national and international exercise of power, or struggle for power, and the relationships between governing bodies and states.
Referrers
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
• Until now, Rhizomer like other Linked Data publishing tools…– HTML+RDFa and content negotiation– Useful for computers, but also for human users?
• User tests:– Typical questions:
• Where do I start? • Where do I go now?• What is this data about?
– What do we offer? • Text search, type URI, SPARQL query,…
…but they do not answer end-users needs
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
• Example: What to do with DBPedia? – 3.5 million things described
• Ontology: 257 classes y 1276 properties
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
– DBPedia main page does not provide too many clues...
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
• SPARQL Endpoint:– select distinct(?c) (count(?i) as ?n)
where {?i a ?c} order by desc(?n)
c n
http://www.w3.org/2002/07/owl#Thing 1668503
http://www.w3.org/2004/02/skos/core#Concept 632607
http://www.opengis.net/gml/_Feature 571764
http://dbpedia.org/ontology/Place 462349
http://dbpedia.org/ontology/Person 363751
http://dbpedia.org/ontology/Work 355100
http://dbpedia.org/ontology/PopulatedPlace 340443
http://dbpedia.org/ontology/Settlement 304370
http://xmlns.com/foaf/0.1/Person 296595
http://dbpedia.org/ontology/Species 168575WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
• Simple search– What to type?
– A URI? URI label?
– …
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Interacting
• Advanced search:– iSparql
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Information Architecture
• Proposal: adapt data interaction patterns [Shneiderman] and Information Architecture components [Morville]– Data structure: automate IA components
– Scalable, dataset independent
• Interaction Patterns / IA Components– Overview --> navigation bars, site map
• Main classes (topics) and their organisation
– Zoom & Filter--> facets, breadcrums• Main properties and values, filter
– Details --> HTML view, Object-Action Paradigm
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
– Get hierarchical structure for dataset ontologies
– For each class• URI
• Label
• # instances
• Subclasses list
– Flatten to desired # levels and elements / level• Classes and namespaces whitelist and blacklist
– Algorithm:• When there is room, divide class with most instances
• When too many options, group classes with less instances
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
7 elements in “Species” submenu:
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Navigation Bars
Navigation bar provides overview for DBPedia… …but what to do with 12.334 birds now?
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Facets
• Pre-compute list of facets for each class– Properties used in dataset instances descriptions– Facet metrics: frequency, #different values, more
common value cardinality, entropy,…
• DBPedia Birds case:– http://dbpedia.org/ontology/Bird 12334 instances– 226 different properties
• http://dbpedia.org/ontology/kingdom, 100%, 3 values, 6846 (Animalia),…
• User unfolds facet, show 5 +common values– Filter, get more…
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Facets
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
AI Components Facets
• Order facets by "utility” (work in progress):– Prefer common properties, high frequency
– For values cardinality, discard extreme cases: • Just 1 value for the property
• All different values, i.e. max. value cardinality = 1
– Prefer properties that evenly divide results, higher entropy
Property Entropy Value InstanceshasFlavor 0.918434 Moderate 28
Strong 15Delicate 10
hasSugar 0.556416 Dry 43Sweet 6OffDry 4
Wine (Wine Ontology)
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
InteractionObject-Action
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
InteractionObject-Action
• Given a resource (object)…determine available services (actions)
• Services descriptions:– endPoint: service location– hasInput: ASK SPARQL Query Template
• Service applicable to any resource ASK is true
– hasOutput: output content type
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
InteractionObject-Action
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Conclusions
• Navigation menus – dataset classes (topics) overview
• Facets – per class properties and values overview, filter
• Details – Generic view (HTML) + specific (map, timeline…)
• Users build queries without SPARQL or dataset structure knowledge
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Future Work
• Facets: – type dependent facets (number ranges, dates,…),
inverse properties, facets for facet values,…
• Other IA components: sitemap, breadcrumbs,…
• Assisted metadata edition– Recommend properties and values based on
available ontologies and values
• More interaction services– Calendar– Plot…
WIMS’11 Conference, May 25th 2011, Sogndal, Norway
Thank you for your attention
More details: http://rhizomik.net/rhizomer
Contact: Roberto Garcia ([email protected])
HCI & Data Integration Research GroupUniversitat de Lleida, Spain