Slides 11

Social Network Analysis (SNA)

The process of investigating social structures through the use of networks and graph theory.

emotional contagion

The process of unconsciously mimicking the emotions of people around you.

betweenness centrality

A way of detecting the amount of influence a node has over the flow of information in a graph.

local clustering coefficient for a node

Is given by the proportion of the number of links between its neighbours divided by the number of links that could possibly exist between them.

clustering coefficient

A clustering coefficient is a measure of the segree to which nodes in a graph tend to cluster together.

global clustering coefficient

Gives us the probability that any two nodes in a network, that have a common neighbor, are connected.

network characteristics

Average of the length of the shortest paths between each two nodes.

Diameter: longest “shortest path”

homophily

The principle that contact between similar people occurs at a higher rate than among dissimilar people.

community detection

The process of discovering groups in a network, given the network graph.

ratio cut

Average of (the amount of) Cuts/Community volume.

Ratio_cut = 1/2*(1/1+1/9)=0.56

information propagation analysis

Studying and modeling how information spreads over the network.

independent cascade model

An information propagation model where the information spreads over the network through cascade.

Diffusion depends on:

• Network topology

• Cascade model

• Content