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A Virtuous Cycle of Semantics and Participation - PhD dissertation
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A Virtuous Cycle of Semantics and Participation
Doctoral dissertation of: Davide Eynard
Advisor: Prof. M.Colombetti
Tutor: Prof. A.Bonarini
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Davide EynardPolitecnico di Milano, 07-04-2009
Introduction
Ch 1
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Davide EynardPolitecnico di Milano, 07-04-2009
Participative systems
A particular class of social systems in which people can interact, share information, or both.
Encyclopedias BookmarksMaps
News Word processorsMusic
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Davide EynardPolitecnico di Milano, 07-04-2009
Participation and semantics
How does the virtuous cycle work?
Data
Structure
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Davide EynardPolitecnico di Milano, 07-04-2009
Motivations
Successful See “What is Web2.0” by Tim O'Reilly On the Internet, but also inside intranets
Interesting from different point of views: Psychology
• Incentives, bootstrap problem HCI
• New interfaces and interaction paradigms Social Sciences
• Collective intelligence, trust KM
• Use meaningful formats for interoperability New technologies
• Scalability, reliability
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Davide EynardPolitecnico di Milano, 07-04-2009
There's Bad and “Bad”
Bad collaborative system Too complex Bad interaction with user No incentives to participate Tool doesn't fit the objective “I love the system – I just don't use it!”
“Bad” collaborative system Users like it Fits tool and community well, but... ... it could be made better with semantics!
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Davide EynardPolitecnico di Milano, 07-04-2009
Research objectives
Given a community, a task and a context
develop a methodology to evaluate whether a system correctly fits an activity
use semantics to make the system better, incentivating user contribution
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Davide EynardPolitecnico di Milano, 07-04-2009
Background
Ch 2
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Davide EynardPolitecnico di Milano, 07-04-2009
Background – Social Systems
Creating and publishing• blogs, wikis, collaborative editors
Communicating• e-mail, forums, chat, microblogging
Sharing• p2p, client-server, social bookmarking
Recommending• implicitly or explicitly, specific or general
Coordinating• calendars, project or knowledge management
Networking• social networks (object centered or not)
Playing• MUD, MMORPG (Second Life)
Market places• auctions, recruitment
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Davide EynardPolitecnico di Milano, 07-04-2009
Background – Basics on social interactions
Wenger, Lave• Communities of Practice• Legitimate Peripheral Participation• see Bryant, Forte, Bruckman:
Becoming Wikipedian
Engeström, Vygotsky• Activity Theory
Image courtesy of University of Helsinki - Center for Activity Theory and Developmental Work Research
Image courtesy of Ross Mayfield's Weblog
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Davide EynardPolitecnico di Milano, 07-04-2009
Background – Semantic Web
“An extension of the current Web, in which information is given well defined meaning, better enabling computers and people to work in cooperation”
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Davide EynardPolitecnico di Milano, 07-04-2009
Our work
Ch 3
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Davide EynardPolitecnico di Milano, 07-04-2009
Our work – Evaluate and design
The Six Ws:
Who• user, community, producer,
consumer What
• tool, object, contents, traces How
• explicit vs implicit participation, coupling
When• sync vs async participation
Where• context, centralized vs
distributed Why
• incentives, engagement
User-centered design:
keep semantics hidden reuse and standardize merge with the activity evolve with complexity
(see D. Norman: “The design of everyday things”)
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Davide EynardPolitecnico di Milano, 07-04-2009
Our work – Extend systems with semantics
SystemContext
Domain
Upper
Semantics have been applied on different levels Link data (“a little semantics goes a long way”, J. Hendler) Better describe knowledge Infer new knowledge with reasoning
When ontologies are used, they are applied on different levels too
[B.1]
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Davide EynardPolitecnico di Milano, 07-04-2009
Experimental developments
Ch 4, 5, 6
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Davide EynardPolitecnico di Milano, 07-04-2009
Semantic Wikis
Wikipedia OMP Intranet
Who
What
How
When Asynchronous Asynchronous
Where Centralized
Why
Generic Internet users who write for everyone
Generic Internet users who write for everyone
Employees with specific addressee (group, boss)
Encyclopedia, divided in articles
Hypertextual book (mostly atomic)
Internal atomic docs, reports, attachments,
annoucements
Contributive, collective, explicit participation
Mostly collective, explicit participation
Contributive, often collective, explicit/implicit
participation
Asynchronous (stronger need for updates!)
Centralized (what about China?)
Centralized in an intranet context (authorship,
confidentiality)
Social/personal incentives, small COP
Social/personal incentives, often just individuals
“Because my boss says so”, groups/labs as COP
Wikis are not all the same:
Semantic extensions: for data (templates for contents – describe knowledge) and metadata (about pages and attachments – describe and infer)
+ ?
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Davide EynardPolitecnico di Milano, 07-04-2009
Folksonomies
Who
What
How
When Asynchronous
Where Usually centralized
Why
Generic Internet users who mostly tag for themselves
Classification technology
Contributive, implicit, low coupling
Personal incentives
Main limits: no synonym control “basic level” variations lack of precision lack of recall lack of hierarchy system-dependent
Folksonomy + Ontology disambiguate words add hierarchy interlink folksonomies (describe and link)
[B.2, B.3, B.5]
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Davide EynardPolitecnico di Milano, 07-04-2009
Annotation Systems: Linking Open (meta)Data
Linking Open Data is: a project which aims at making data freely available to anyone,
setting RDF links between items from different data sources a paradigm to publish information on the Web
Metadata = information about information anything which has a URI can be commented (or annotated) common limits of annotation systems:
• low user incentives• cannot reuse metadata over different systems
LOD as a possible solution• provides a large data base to bootstrap system• suggests a widespread, machine interpretable standard for
information sharing and reuse• what about linking other types of data?
[D.1, B.4, D.2]
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
Ch 7
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
we chose a topic
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
we chose a topicwe extended it
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
we chose a topicwe extended it(in different directions)
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
we chose a topicwe extended it(in different directions)this allowed us to study it from other perspectives
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
we chose a topicwe extended it(in different directions)this allowed us to study it from other perspectives
Results the behavior and the success of a
participative system depend on many different factors (i.e. community, incentives, context)
we developed a general methodology to evaluate participative systems and technologies and we applied it to some specific cases
for each of these cases, we used semantics to build better tools
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
Our contributions General
• our methodology does not depend on a particular system Specific
• we applied semantics on different levels (and not just on contents) to build a better intranet wiki;
• we applied semantic disambiguation techniques to address some of the most important problem of folksonomies and provided a new, hierarchical interface to browse tag-based systems;
• we suggested a solution to the bootstrap problem, which employs already available open data sources to provide a user incentive;
• by converting email and web history to a standard and shared representation, we automatically linked two of the most accessed data repositories to a huge amount of related information.
Limits Our evaluations were mostly focused on datasets and
algorithms
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Davide EynardPolitecnico di Milano, 07-04-2009
Conclusions
Future work Develop a model for the evaluation, the extraction, and the
reconciliation of data coming from different and heterogeneous data sources
Delve deeper into the intelligent part of collective intelligence
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Davide EynardPolitecnico di Milano, 07-04-2009
The end
Thank you! Questions?
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Davide EynardPolitecnico di Milano, 07-04-2009
Relevant publications
[D.2] Eynard, D. (2008) Using semantics and participation to customize personalization. HP Labs Technical Report HPL-2008-197.
[B.5] Bindelli, S., C. Criscione, C.A. Curino, M.L. Drago, D. Eynard, & G. Orsi (2008). Improving Search and Navigation by Combining Ontologies and Social Tags. Proc. of the 1st International Workshop on Ambient Data Integration, Monterey, Mexico.
[B.4] Eynard, D., & M. Colombetti (2008). Exploiting user gratification for collaborative semantic annotation. Proc. SWUI 2008.
[B.3] Laniado, D., D. Eynard & M. Colombetti (2007). Using WordNet to turn a folksonomy into a hierarchy of concepts. Proc. 4th Fourth Italian Semantic Web Workshop, 192–201.
[B.2] Laniado, D., D. Eynard & M. Colombetti (2007). A semantic tool to support navigation in a folksonomy. Proc. 18th Conference on Hypertext and Hypermedia (ACM Press, New York), 153–154,.
[D.1] Eynard, D., J. Recker & C. Sayers (2007). An IMAP plugin for SquirrelRDF. HP Labs Technical Report HPL-2007-161.
[B.1] Eynard, D. (2007). Research on collaborative information sharing systems. Proc. Knowledge Web PhD Symposium 2007, 81–82.
Contact Davide Eynard
http://www.dei.polimi.it/people/eynard
Tel. 02 2399 4010
Fax 02 2399 3411
Back
Project page @AIRLab: http://airwiki.elet.polimi.it
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Davide EynardPolitecnico di Milano, 07-04-2009
Semantic Wikis
Data• semantic templates using a domain ontology
Metadata• automatic extraction and ontology supported management of
attachment metadata• context ontology to describe properties and relations between
documents
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Davide EynardPolitecnico di Milano, 07-04-2009
Annotation Systems: Linking Open (meta)Data
Email• An automatic IMAP to RDF translation tool• Information can be queried on the fly with
SPARQL, saved in RDF and piped to external services
Browser history• Linking history data (visited or bookmarked
URLs) with related, already available metadata from Freebase
Semantic Annotation Tools• Exploiting user gratification for collaborative
semantic annotation
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Davide EynardPolitecnico di Milano, 07-04-2009
Linking Open (meta)Data
Browser Linking history data (visited or bookmarked URLs) with related,
already available metadata
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Davide EynardPolitecnico di Milano, 07-04-2009
Linking Open (meta)Data
Semantic Annotation Tools Exploiting user gratification for collaborative semantic annotation
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Davide EynardPolitecnico di Milano, 07-04-2009
Annotation systems
Speakinabout architecture:
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Davide EynardPolitecnico di Milano, 07-04-2009
Taxonomy of participation - a total mess!
social
participative/collective
contributive
do/create
suggest
share
alone with others
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Davide EynardPolitecnico di Milano, 07-04-2009
Levels of participation - The county fair example
• many people participate (take part) to the event• some contributed with suggestions, actions or resources• some collaborated to organize it• some are just there to have fun, or for their business• ... but the fair success depends on all of them!• see Engeström's Activity Theory
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Davide EynardPolitecnico di Milano, 07-04-2009
1) Structure data
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Davide EynardPolitecnico di Milano, 07-04-2009
Folksonomies: datasets and stats
x axis: tags ordered by usagey axis: percentage of tags belonging to WordNet
We have collected a large dataset from del.icio.us that allowed us to study tags statistically.