http://ceur-ws.org/Vol-902/paper_7.pdf Knowledge on the Web comes in ever larger amounts and in a wider variety of structure and semantics that ever before. In or- der to exploit this knowledge in dierent applications, many researchers investigate techniques for making sense of Web data. Objects that the techniques try to identify and extract are, for example, people, organiza- tions, and locations. Many applications though observe how events play an increasingly more important role. Capturing and extracting events for sense making analysis is what this research is aiming for, and in this paper we present the rst results and contributions from our research. We consider how events get extracted, how they get conceptualized, and how visual analytics helps to make sense of the represented events. All of this is illustrated in a representative example where driven by questions from social scientists we apply our pipeline to the domain of activism, e.g. Occupy, Arab Revolution.

1. Making Sense of the Arab
Revolution & Occupy
Extracting, Aggregating & Visualizing Events
Thomas Ploeger, Bibiana Armenta,
Lora Aroyo, Frank de Bakker, Iina Hellsten
Monday, November 12, 12

2. When we talk about
events we want to know ...
• Which activists were most active in 2011?
• Which Dutch activist organizations have been
involved in labour strike events?
• What type of activists events happened in
Berlin last year?
• What is the most popular activist event so far?
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3. When we talk about
events we want to know ...
• Which activists were most active in 2011?
• Which Dutch activist organizations have been
involved in labour strike events?
• What type of activists events happened in
Berlin last year?
• What is the most popular activist event so far?
Monday, November 12, 12

4. Types of queries
• Descriptive
• What are the properties of the networks that are formed around
a campaign?
• Which tactics activist groups apply most often to influence norms
of companies on issues of CSR?
• Narrative
• Which actors use a specific tactic at a specific point in time?
• Interpretative
• How does non-traditional media influence activist groups' tactics
and positions (blogs, social media in general)?
• Why is one form of tactic chosen by an activist group rather than
another one?
• Is it related to the campaign, or to the targeted company
• Is it related to the time, technology, place, or culture?
• Is it related to the tradition of this group?
Monday, November 12, 12

5. Types of queries
• Descriptive
• What are the properties of the networks that are formed around
a campaign?
• Which tactics activist groups apply most often to influence norms
of companies on issues of CSR?
• Narrative
• Which actors use a specific tactic at a specific point in time?
• Interpretative
• How does non-traditional media influence activist groups' tactics
and positions (blogs, social media in general)?
• Why is one form of tactic chosen by an activist group rather than
another one?
• Is it related to the campaign, or to the targeted company
• Is it related to the time, technology, place, or culture?
• Is it related to the tradition of this group?
Monday, November 12, 12

6. Occupy Wall Street
a police officer sprayed 4 protesters with pepper spray
• Protesters argued that the use of pepper spray was uncalled for vs. necessary
(NYPD defended the officer)
• The officer stated that the event was taken out of context vs. at fault
(investigation concludes that the officer was at fault and he was reprimanded)
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7. Self-immolation of MB
Mohamed Bouazizi, Tunisian street vendor set himself on fire to protest after
officials confiscated his wares.
• personal, economic motivation vs. martyr
• the spark that ignited Tunisian Revolution & Arab Spring vs. singular personal event
• How was he treated by officials when they confiscated his wares?
• How did officials respond to his complaints?
• Are there any earlier encounters between him and officials?
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8. Why is it difficult?
• Information is
• scattered across different sources
• offered in different formats
• often incomplete, incorrect, out of context, bias
• Events are
• perceived from different points of view
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9. Mapping Online Networks of Activism
alleviating bias by modeling & visualizing activist
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10. Activist Events Terminology
• Activist Event: an action undertaken by an actor as part of a
campaign with the aim of influencing the state (e.g. resolved)
of an issue
• Tactic: indicates the event type
• Actor: a person, group or organization of a given type (e.g.
radical, reformative) performing tactics
• Company: an organization that triggers an issue
• Issue: a topic or problem important to actors and companies
• Campaign: consists of a set of events undertaken by an actor
aiming to influence the state of an issue
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11. Modeling Activist Events
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12. Modeling Activist Events
campaign-centered
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13. Modeling Activist Events
event-centered
campaign-centered
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14. ACTEVE-SEM
ACTivist EVEnts model based on Simple Event Model
• actors, roles, objects, places, times
• viewpoints (according to a certain authority), i.e.
attribution of authoritative source of a statement
time-bounded validity of facts
event-bounded roles
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15. Example I
Event that is reported differently by multiple sources
Multiple
Sources
Multiple
Representations
All versions shown
visually, comparatively
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16. Example I
Event that is reported differently by multiple sources
event-bounded roles of actors, e.g. police
officer - aggressor vs. peacekeeper
Multiple sem:View sem:Authority
Sources
Multiple
Representations
All versions shown
visually, comparatively
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17. Example II
Event that is reported with or without incorrect context
Earlier
Source Events
Material
Event
Representation
Event shown in context
of earlier events
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18. Example II
Event that is reported with or without incorrect context
Earlier
Source Events
Material
Event
Representation
time-bounded validity of facts, e.g.
Mr. Bouazizi - street vendor vs. martyr
sem:Temporary
Event shown in context
of earlier events
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19. Candidate Events & Entities
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20. Candidate Events & Entities
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21. Timelines from Text
set of events partially ordered by time, e.g. before/after
“al-Qaeda activities in Syria”
4 right, 2 wrong, 3 missing events
two have no explicit times & are in the wrong order
One involved al-Qaeda but took place in Jordan on the Syrian border
does a fuzzy task require fuzzy metrics?
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22. Metrics
• how to measure partial & overall correctness,
• compared to the worst/optimal/best timeline
• how timeline should optimize for missing data, e.g. times,
locations (deduce temporal and spatial position)
• in context of the task or purpose it is used for
• for a given type of queries
• how to determine importance of events (also in context)
• how to determine importance of dimensions (also in context)
• are there dependencies between the different dimensions
• measuring overall coherence of timeline
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25. When visualizing ...
• Adjusting the granularity in
terms of times, locations and
event types
• Comparing different
perspectives on the same
event
• Showing evolution over time of
event types, event participants
or location
• Filtering events based on
(strength of) connections to
other events, participants,
places or periods
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32. Questions?
@laroyo
http://lora-aroyo.org
Monday, November 12, 12