Social Networks & Data

Got a chance to attend amazing talk by Prasanta Bhattacharaya (https://www.linkedin.com/in/prasantabhattacharya/?ppe=1)

at PyDataSG https://www.meetup.com/PyData-SG/events/235981787/

Started with your favorite Game of Thrones network (I swear i still havent seen a single episode.)

Every betrayal ever…

Building Social network for Game of Thrones.

History Of Social Networks

  • Euler was probably the first one to give an algo for a social network. He came out with a theorem called Konigsberg 7 bridges problem in 1736.
  • The first data came after almost a century from Pierre Huber in 1802, with Social structure of Bumblebees.
  • MRT is an offline network. Recently Channel News asia published infographics for MRT delay vs mean distance travelled. Green line is doing worse.

http://www.channelnewsasia.com/news/singapore/overall-rail-reliability-improves-but-serious-delays-increase-lt-7569598

How nature compares with human engineers.

http://moviegalaxies.com/

Basic Network properties

  • Actors & relations <nodes /edges>
  • Relations <directed vs undirected ; binary vs valued(weighted)>

Storing network Data

  • Adjacency Matrices
  • Adjacency List
  • Edge List <most common form of network data>

Node Level Attributes

Degree Centrality

  1. Closeness Centrality : measure of distance of node from all other nodes
  2. Betweenness Centrality : Measure of all the shortest distance from a node
  3. Eigenvector Centrality : Measure of the influence of a node in a network.

(Google Pagerank uses eigenVector )

Research Challenges

Two broad area

  1. struct & evolution
  2. Process
  • why ppl make friend
  • what information spread
  • how disease spread

3. But Structure & processes are genereally cofounded

Favorite research area — “peer influence”

  • for a person i, intervention on Xi leads to outcome of Yi
  • But what about intervention on Yj where path (i,j) exists

Peer influence :

  1. If your friend buys iPhone, how soon will you buy one

2. Spread of disorders

3. Voting behavior

HOMOPHILY or Peer Influence

Hypothetical story from Solizi & Thomas (2011)

  • Two friends = Joey & Ian if Joey friend jumps of bridge , would Ian jump off too
  • Why would you jump off bridge (6 explanations)

Social Advertising

Showing social cue gets more clicks ?

Research paper from Facebook

Like Rate increases with D (number of peers shown), this is targeted Ad

and shows Homophily.

Usually social networks do A/B testing on social network does either at New Zealand or does Graph cluster randomization