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"EventMedia Live: Exploring Events Connections in Real-Time to Enhance Content" presented at the Semantic Web Challenge, Open Track, of the 11th International Semantic Web Conference, Boston, USA, November 2012
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EventMedia Live: Exploring Events Connections in Real-Time to
Enhance Content
Houda Khrouf, Vuk Milicic and Raphaël Troncy
{khrouf,milicic,troncy}@eurecom.fr
@rtroncy
Semantic Web Challenge, ISWC 2012, Boston
Events through the web …
14/11/2012 Semantic Web Challenge - ISWC 2012 - Boston 2
Event Directories
Media Platforms
Social Networks
Allows opportunistic/serendipitous discovery Limited social features and Information incompleteness (low coverage, weak decision)
Aids remembering and sharing past experiences Lack of consistent events descriptions
Attendance: popularity and friends' whereabouts, attendees’ opinions. Limited discovery mechanism: need to filter out relevant information.
Explore semantic connections to create better overviews of events
Approach
Semantic Web Challenge - ISWC 2012 - Boston 3 14/11/2012
Aggregate heterogeneous data sources Unify into one data model using Semantic
Web technologies Enrich with media, social data and
background knowledge
Identify meaningful and/or interesting relationships between events, media, and people
User Tasks and Challenges
Semantic Web Challenge - ISWC 2012 - Boston 4
Goals: Discover PAST, PRESENT and FUTURE events Live, relive and predict experiences through shared media Enhance search and recommendations mechanisms Support the decision making process
Challenges Semantization of Data (events, media, people) Reconciliation of sparse and highly heterogeneous data User-centric design: discovering, deciding and recommending Scalability, Caching and Optimization
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Architecture
Semantic Web Challenge - ISWC 2012 - Boston 5
Real-time Reconciliation
- Tag-based mapping - Instance matching
Heterogeneous data sources
Data Crawling RDF Conversion
RSS Update
Web Applications
SPARQL REST API (Elda)
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Semantic Web Challenge - ISWC 2012 - Boston 6
Data Crawling
Various API specifications
Policy management
Requests chaining
Different input and output schemas
Time-consuming
A Restful Service leveraging the commonalities of API specifications
A Web dashboard to easily handle data collection and interlinking http://eventmedia.eurecom.fr/dashboard/
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Semantic Web Challenge - ISWC 2012 - Boston 7
Data Modeling – LODE ontology
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LODE is a minimal model that encapsulates the factual properties of events: What, Where, When and Who.
Real-Time Reconciliation
Semantic Web Challenge - ISWC 2012 - Boston 8
Participants Media
Cost & description
Precise time agents
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Need for semantic connections between events, media, agents and locations
Events and Media connections
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1.7 million images over 126.000 events
Machine tags “lastfm:event=”
“upcoming:event=”
APIs
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Semantic Web Challenge - ISWC 2012 - Boston 10
Live Update
Tag = *:event
Per week
• 1500 Photos • 130 events
Number of Items posted per days of the week Number of Items posted during the last days
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Instance Matching
Events/Agents/Locations semantic connections SPARQL-based Instance matching Filtering by the issuance date
Challenges Structural heterogeneity Different representations of the same value User-generated knowledge featuring human mistakes Different granularities between data sources
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The events similarity is a mutual agreement of their factual properties Based on top-k dependencies between properties
Evaluation: Precision: 96% and Recall: 94% Ground truth of 300 matched instances
Semantic Web Challenge - ISWC 2012 - Boston 12
Events connections
p1 p2 dependency
title1 title2 0.30
place1 place2 0.28
title1 agent2 0.26
agent1 agent2 0.21
description1 title2 0.16
Minimal conditions to fetch similar events using SPARQL
1st level
Refine the results 2nd level
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Agents connections (precision-oriented)
Internal reconciliation + DBpedia, Musicbrainz and BBC
Label matching + contextual filtering (Cosine) Granularity? (1 to N mappings) Cosine inequality
Locations connections (precision-oriented)
Internal reconciliation + DBpedia and Foursquare It is straightforward thanks to the consistency of locations descriptions Top-k Google search Geographical distance
Semantic Web Challenge - ISWC 2012 - Boston 13
Agents & Locations connections
Cosine (d, a+b) > Cosine (d ,a)
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About the dataset
SPARQL endpoint: http://eventmedia.eurecom.fr/sparql
Restful API : http://eventmedia.eurecom.fr/rest/event/
Semantic Web Challenge - ISWC 2012 - Boston 14
Event Agent Location Photos User
Last.fm 61,173 62,577 15,917 1;464,885 130,249
Upcoming 19, 276 15 10,269 308,148 3,932
Eventful 45,204 8,725 18,763 3,028 321
Total 125,650 71,313 44,948 1,760,787 159,263
DBpedia MusicBrainz Eventful Last.Fm 13064 34247 2865 Eventful 2515 3616 -
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Web Application
Challenges: Modern single-page app on top of semantic technologies
Fast, user-friendly and responsive UI
Dealing with high variability of data
Technologies: Backbone.js: MVC framework enables complex UI,
provides flexibility
Elda Linked Data API maps SPARQL queries to RESTful URLs
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What's the added value of SW?
Data model (RDF) + URIs for all objects + decentralized semantics (re-use of ontologies) = life MUCH easier for data integration
Re-use data of others … DBpedia, MusicBrainz, BBC, Foursquare, etc.
… and expose our reconciled data (CKAN)
Toolkits: Virtuoso: triple store + SPARQL endpoint + RDF publishing
Silk / Knofuss: several similarity metrics for instance matching
Elda (Linked Data API)
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Semantic Web Challenge criteria
Attractive/Functional UI: fluid navigation, multimedia
Scalable application: 40 million triples and counting
Novelty: real-time events connections discovery
Use of dynamic data: social media, rss feeds
Cross languages, cross devices: phones, tablets
Commercial potential: ask the entrepreneurs here!
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What's on this evening?
Semantic Web Challenge - ISWC 2012 - Boston 19 14/11/2012
What's on this evening?
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Demo: Live your event
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http://eventmedia.eurecom.fr
Future Work
User interface: aggregated views of events, agents, locations and users.
Opinionated content retrieval: social networks, online newspapers, etc.
Identify Interests and provide recommendations
Analysis of social networks activities around real-world events (behavioral patterns)
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http://www.slideshare.net/troncy
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