Difference between revisions of "Popescu and Pennacchiotti, CIKM 10"

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Events are defined in relation to a target entity, which is an activity with a clear, finite duration in which the target entity plays a key role.
 
Events are defined in relation to a target entity, which is an activity with a clear, finite duration in which the target entity plays a key role.
The event is considered controversial if it provokes a public discussion in which audience members express opposing opinions or disbeliefs. This is in contrast to events which have little reaction or are overwhelmingly positive/negative (i.e high entropy in opinions).
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The event is considered controversial if it provokes a public discussion in which audience members express opposing opinions or dis-beliefs. This is in contrast to events which have little reaction or are overwhelmingly positive/negative (i.e high entropy in opinions).
  
 
The authors seek to extract such snapshots of controversial events by modeling the task as a supervised machine learning problem. Each snapshot is represented by a feature vector constructed from Twitter  and other sources (such as news).
 
The authors seek to extract such snapshots of controversial events by modeling the task as a supervised machine learning problem. Each snapshot is represented by a feature vector constructed from Twitter  and other sources (such as news).
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They make extensive use of lexicons such as  
 
They make extensive use of lexicons such as  
# Controversy lexicon derived from Wikipedia's controversial topic list
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# Controversy lexicon derived from Wikipedia's controversial topic list [http://en.wikipedia.org/wiki/Wikipedia:List_of_controversial_issues]
# Bad words lexicons [http://urbanoalvarez.es/blog/2008/04/04/bad-words-list/]
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# [[UsesDataset::Bad words lexicon]] [http://urbanoalvarez.es/blog/2008/04/04/bad-words-list/]
  
 
They used features to capture an event snapshots' linguistic properties, structural information (graph), intensity of discussion about an entity and distribution of sentiment words in the event.
 
They used features to capture an event snapshots' linguistic properties, structural information (graph), intensity of discussion about an entity and distribution of sentiment words in the event.
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They manually labeled 800 tweets for events. Their data is not released, although they achieved high kappa score (inter annotator agreement) for their labeled data.
 
They manually labeled 800 tweets for events. Their data is not released, although they achieved high kappa score (inter annotator agreement) for their labeled data.
They compared their differnt models by ranking quality and average precision.
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They compared their different models by ranking quality and average precision.
 
The blended model seemed to perform best on their dataset.
 
The blended model seemed to perform best on their dataset.
  
Hashtags were one of the most discriminative features for event detection. Coupling tweets with news and external sources were also useful as they help to validate and explain social media reactions.
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Hashtags were one of the most discriminating features for event detection. Coupling tweets with news and external sources were also useful as they help to validate and explain social media reactions.
  
 
== Discussion ==
 
== Discussion ==

Revision as of 22:54, 30 September 2012

This Paper is relevant to our project on detecting controversial events in Twitter.

Detecting controversial events from Twitter

Citation

Ana-Maria Popescu and Marco Pennacchiotti. Detecting controversial events from Twitter. In Proceedings of the 19th ACM international conference on Information and knowledge management, CIKM ’10, pages 1873–1876, New York, NY, USA, 2010. ACM.

Online version

Detecting controversial events from Twitter

Summary

This paper addresses the task of identifying controversial events using Twitter as a starting point.

Events are defined in relation to a target entity, which is an activity with a clear, finite duration in which the target entity plays a key role. The event is considered controversial if it provokes a public discussion in which audience members express opposing opinions or dis-beliefs. This is in contrast to events which have little reaction or are overwhelmingly positive/negative (i.e high entropy in opinions).

The authors seek to extract such snapshots of controversial events by modeling the task as a supervised machine learning problem. Each snapshot is represented by a feature vector constructed from Twitter and other sources (such as news). They present several models for comparison, a direct model using regression, a 2-step pipeline model where one detects events and then measure its controversy, and a 2-step blended model where the results of the event detection step are used as an input to the controversy detection regression model.

They make extensive use of lexicons such as

  1. Controversy lexicon derived from Wikipedia's controversial topic list [1]
  2. Bad words lexicon [2]

They used features to capture an event snapshots' linguistic properties, structural information (graph), intensity of discussion about an entity and distribution of sentiment words in the event. Furthermore, they also align news articles to snapshot tweets and see how many news articles mentions the target entity significantly.

Evaluation

They manually labeled 800 tweets for events. Their data is not released, although they achieved high kappa score (inter annotator agreement) for their labeled data. They compared their different models by ranking quality and average precision. The blended model seemed to perform best on their dataset.

Hashtags were one of the most discriminating features for event detection. Coupling tweets with news and external sources were also useful as they help to validate and explain social media reactions.

Discussion

Related papers

There has been a lot of work on event detection.

Study plan

  • Article: Adaptive time series model [3]
  • Graph cut based clustering [4]