Computational Analytics in SPOD platform.

1. Computational Analytics in SPOD
Gennaro Cordasco, Carmine Spagnuolo, Vittorio Scarano

2. ROUTE-TO-PA Prato Plenary Meeting
Overview
15/9/2015
Introduction
Some example
Some Metrics and Methods
Social and Data Network Analysis (SDNA) in SPOD
Discussion
Gephi: The Open Graph Viz Platform
Network over time

3. ROUTE-TO-PA Prato Plenary Meeting15/9/2015
Introduction
Social
Network
Analysis

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The power of social networks

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What is a social network?

6. • 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

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Some
Examples

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Friendship network

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Email network
Nodes = People
Links = Emails
Source: orgnet.com

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Karate Club

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Romantic and Sexual Relations

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Football: Spain won 2010’s World Cup

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What can we learn by using these models?
ROUTE-TO-PA Prato Plenary Meeting

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• 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

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Metrics
and
Methods

16. • 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

17. • 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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Network
over
the
Time

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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.

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in
Social
SPOD
and
Data
Analysis
Network

21. • 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

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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.

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Gephi
and
visualization
exploration

24. • 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

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Discussion

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Discussion
• Goals
• Networks
• Ideas