route-to-pa computational analytics in spod
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Computational Analytics in SPOD Gennaro Cordasco, Carmine Spagnuolo, Vittorio Scarano
ROUTE-TO-PA Prato Plenary Meeting
Overview
15/9/2015
IntroductionSome example
Some Metrics and Methods
Social and Data Network Analysis (SDNA) in SPOD
DiscussionGephi: The Open Graph Viz Platform
Network over time
ROUTE-TO-PA Prato Plenary Meeting15/9/2015
IntroductionSocial
NetworkAnalysis
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
The power of social networks
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
What is a social network?
•Social network analysis and data mining:– Detection of criminal activity, counter-terrorism, homeland security,
and intelligence– Analysis of relationships within companies– Sociological and anthropological studies– Reciprocal trust schemes such as eBay ratings– Recommended friends on Facebook– Filter or recommend social media content
• – …
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Applications of social networks
ROUTE-TO-PA Prato Plenary Meeting15/9/2015
SomeExamples
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Friendship network
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Email network
Nodes = People Links = Emails Source: orgnet.com
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Karate Club
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Romantic and Sexual Relations
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Football: Spain won 2010’s World Cup
15/9/2015
What can we learn by using these models?
ROUTE-TO-PA Prato Plenary Meeting
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
• Can we mine SPOD data in order to:• support other analysis (like Dialogue
Games)? • encourage users participation?• identify skilled and/or reliable users?• …
• Idea: assuming that we are able to model the data according to some relationships between different entities:
• we can exploit Network analysis tools.
Network analysis in SPOD
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Metricsand
Methods
• Assumption: important actors are involved with others extensively.
• The problem is find out automatically which are the central actors.
• Metrics:• Closeness Centrality• Betweenness Centrality• Eigenvalue Centrality• Prestige• PageRank Algorithm• Hits Algorithm• …
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Centrality
• Methods:o community detection is key to
understanding the structure of networks.
• In SPOD it can be used to• identify users with common interest (and
suggest friendship);• identify related data;• suggest the proper way of visualizing data.
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Community detection
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Networkover
theTime
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Networks over time• Does the leader of a discussion change over time?
• Is it true that participate actively in a discussion enhances users’ ability?
• Dynamic graph analysis (DGA) is a novel approach for Network analysis.
• DGA analyses how a network and its metrics evolve over time.
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
in
Social
SPOD
andData
AnalysisNetwork
• It is easy to analyse a snapshot of a Network at time t (Gephi does it for you).• The key point is to identify the Network structure and semantics
• Different goals require dedicated approaches and are based on different networks.• For instance, if we are going to study interaction among users, we need a network
where: • the users are the entities; • the relations are "who communicate with whom”.
• Even in this simple case, we should also define some timing intervals in order to evaluate whether the interactions change along the time.
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Social and Data Network Analysis (SDNA) in SPOD
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Social and Data Network Analysis (SDNA) in SPOD
• Another approach could be define a network that map users and data as a Users-Datalets Network.
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Gephi
andvisualization
exploration
• Gephi is an open-source network analysis and visualization software package.
• Gephi offers the most common metrics for network analysis:
• Betweenness Centrality;• Closeness;• Diameter;• Clustering Coefficient;• PageRank;• Community detection;• …
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Gephi: The Open Graph Viz Platform
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Discussion
15/9/2015 ROUTE-TO-PA Prato Plenary Meeting
Discussion
• Goals• Networks• Ideas
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