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Analyzing User Modeling on Twitter for Personalized News RecommendationsBest Paper of Conference on User Modeling, Adaption and Personalization (UMAP’11)Authors: Fabian Abel, Qi Gao, Geert-Jan Houben and Ke Tao
Unit for Social Software
Presenter: Guangyuan Piao
Reading Group, 29/09/2015
Contents• Background & Related Work
• Design Options for User Modeling in Online Social Networks for Recommendations
• Research Questions
• Dataset for the study
• Study for Research Questions 1,2
• Experiment for Research Question 3
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User Modeling in Online Social Networks for Recommendations
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Related Work
Representation of a User Model• bag-of-words, Chen et al. for recommending and ranking URLs
posted in Twitter messages
Study of hashtags in Twitter• investigate the specificity, stability over time, Laniado & Mika• temporal dynamics of hashtags, Laniado & Mika / Huang et al.
Enrichment of tweets• Exploit metadata of research papers to enrich the semantics of
tweets for mapping tweets to conference talks, Rowe et al.
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Design Options for User Modeling
Semantic Enrichment
Profile Type
Time Constraint
1. tweet-based2. further
enrichment1. hashtag-based2. entity-based3. topic-based
1. time period2. temporal patterns
User Profile
… iPhone
0.09 … 0.08P(u) =
link news
monitorednews pool
an entity-based profile
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Research Questions1. how does the semantic enrichment impact the
characteristics and quality of Twitter-based profiles?
2. how do (different types of) profiles evolve over time? Are there any characteristic patterns?
3. how do the different user modeling strategies impact personalization (personalized news recommendation) and does the consideration of temporal patterns improve the accuracy of the recommendations?
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Dataset for the study Collected from Twitter with more than
• 20,000 Twitter users
• 2 months
• 10,000,000 tweets
• 75,000 news articles
Sample dataset for study
• 1,619 users with at least 20 tweets & 1 tweet/month (2,316,204 tweets)
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Research Question 1
how does the semantic enrichment impact
the characteristics and quality of Twitter-based profiles?
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• tweet-only-based user modeling, fails to create profiles for 100 users
• by enrichment with entities and topics obtained from linked news articles ➡ a higher # of distinct concepts and variety for per profile
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The impact of news-based enrichment
• entity-based and topic-based strategies have higher coverage
Comparison of different types of profiles
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Research Question 2
how do (different types of) profiles evolve over time?
are there any characteristic patterns?
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• profile difference is measured by d1-distance
• user profiles change over time: the older a profile the more it differs from the current profile of the user
Profile difference over time
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d1 = 2
iPad iPhone
Px(u) 1 0Py(u) 0 1
• the difference of weekday and weekend profiles is higher than that of other temporal patterns
Profile difference of weekday and weekend
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• hashtag-based & entity-based profiles change most while the types of entities people refer to (person, product etc.) do not differ strongly
Profile difference of weekday and weekend
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how do the different user modeling strategies impact personalization (personalized news
recommendation)?
and does the consideration of temporal patterns improve the accuracy of the recommendations?
Research Question 3
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Evaluation Setup for News RecommendationsMain goal: analyze and compare the applicability of the different user modeling strategies in the context of news recommendations.
Recommendation algorithm: cosine similarity between user profile and tweets.
Evaluation Metrics:• MRR (Mean Reciprocal Rank): at which rank the first item
relevant to the user occurs on average.• S@k (Success at rank k): the mean probability that a relevant
item occurs within the top k of the ranking, k=10.
observation time period for Twitter
last week
used for user modelingget candidate news items
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Results for News Recommendations – impact of news-based enrichment
• entity-based strategy is better than others
• exploiting both tweets and linked news articles for creating user profiles improves the performance significantly (p < 0.05)
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Results for News Recommendations – impact of considering temporal patterns
• fresh user profiles for topic-based user modeling are more applicable for recommending news articles, while complete user profiles for entity-based user modeling yields better recommendations.
• similar patterns can be found for weekend news recommendations.
(fresh profile: two weeks before recommendation time)
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Conclusions
Further enrichment with semantics extracted from news articles• enhanced the variety of the constructed profiles • improved the accuracy of news article recommendations
Temporal dynamics of user profiles• user profiles change over time• user vary from weekdays and weekends• consideration of temporal dynamics is beneficial to news
recommendations for topic-based user modeling strategy
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