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Network Graphs

Visualizing with Gephi

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Graphs

Mathematical concept Composed of two elements

Nodes Edges

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Nodes

Actors, entities Expressed as points on the graph Anchors for ...

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Edges

Express a relationship between nodes Represented as a line between two nodes

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Two types of edges

Directed One-way relationship Author → Book Graph composed of

only directed edges is a “force-directed graph”

Undirected Expresses a simple

relationship Mutual applied equally to

both nodes Friend ↔ Friend

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Edges & Centrality

Centrality is a measure of connected-ness i.e. numbers of edges for each node

Centrality measures can be quite exotic Various scopes of centrality

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Other measures

Modularity Insular / densely connected communities

In-degree / Out-degree Only applies to directed graphs How many ways can you “travel” to Node A from any other node?

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Formatting data

CSV – Comma Separated Values

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Formatting data

Edge table Source Target Weight

Node table ID Label Attributes

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Data!

http://myweb.fsu.edu/mmiguez/doc/gephiData01.csv

http://myweb.fsu.edu/mmiguez/doc/gephiData02.csv