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PyData SV 2013 Talk by Christopher Roach
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Intro to Network ScienceChristopher Roach
19 Mar 2013
(1)
(3)
WTF?
Agenda
What is it?
Why now?
How do you use it?
Example
Complexity
Complexity
(2)
(2)
History
Math
(Sociology)
Computer Science
Network Characteristics
Degree Centrality
(i) = Cddeg(i)|N| ! 1
nodes = [...]degree = sum([is_neighbor(i, j) for j in nodes])degree_centrality = degree/(len(nodes) - 1)
Closeness Centrality
= li1
|N| ! 1!j"i
di,j
(i) = Cc1li
def distance(i, j): ...
nodes = [...]total_distance = 0for j in nodes: total_distance += distance(i, j)avg_distance = total_distance/(len(nodes) - 1)closeness_centrality = 1/avg_distance
Betweeness Centrality
(i) = (i) Cb1
!st!
st
!st
Eigenvector CentralityPageRank
geodesic (path)eccentricitydiameter
radiuscenter
peripherydensity
Example
Demo
Community Detection
Senate Party Affiliation
Senate Communities
https://github.com/croach/pydata2013
References(1) Skitter data depicting a macroscopic snapshot of Internet connectivity, with
selected backbone ISPs (Internet Service Provider) colored separately by K. C. Claffy, Email: [email protected], http://www.caida.org/publications/papers/bydate/index.xml
(2) Running the Numbers: An American Self-Portrait by Chris Jordan, [email protected], http://chrisjordan.com
(3) Map of internet : 29 June 1999 by William R. Cheswick, [email protected], http://www.cheswick.com/ches/map/gallery/index.html
