Stefano Boccaletti Complex networks in science and society *Istituto Nazionale di Ottica Applicata - Largo E. Fermi, 6 - 50125 Florence, ITALY *CNR-Istituto dei Sistemi Complessi * MIND- Mediterranean Institute for Nonlinear Dynamics Coworkers: Dong-Uk Hwang, Mario Chavez, Andreas Amann,Vito latora Hector Mancini, Jean Bragard, Louis Pecora, Juergen Kurths Dedicated to the memory of Carlos Pérez Garcia PAMPLONA 2005
28
Embed
S tefano Boccaletti Complex networks in science and society
S tefano Boccaletti Complex networks in science and society. * Istituto Nazionale di Ottica Applicata - Largo E. Fermi, 6 - 50125 Florence, ITALY *CNR-Istituto dei Sistemi Complessi * MIND- Mediterranean Institute for Nonlinear Dynamics. Coworkers: - PowerPoint PPT Presentation
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Stefano BoccalettiComplex networks in science and society
*Istituto Nazionale di Ottica Applicata - Largo E. Fermi, 6 - 50125 Florence, ITALY
*CNR-Istituto dei Sistemi Complessi
* MIND- Mediterranean Institute for Nonlinear Dynamics
Coworkers:Dong-Uk Hwang, Mario Chavez, Andreas Amann,Vito latora Hector Mancini, Jean Bragard, Louis Pecora, Juergen Kurths
Dedicated to the memory of Carlos Pérez GarciaPAMPLONA 2005
Summary
•WHAT IS A NETWORK?
•WHAT IS A COMPLEX NETWORK?
•THE STRUCTURE OF COMPLEX NETWORKS
•THE MODELS OF COMPLEX NETWORKS
Do you want to know more? S.Boccaletti, V. Latora, Y. Moreno, M. Chavez, and D.-U. Hwang
Links: social relationship (family/work/friendship/etc.)
S. Milgram (1967)
John Guare Six Degrees of Separation
Social networks: Many individuals with diverse social interactions between them.
Communication networksThe Earth is developing an electronic nervous system, a network with diverse nodes and links are
-computers
-routers
-satellites
-phone lines
-TV cables
-EM waves
INTERNET BACKBONE
Erdös-Rényi model (1960)
Pál ErdösPál Erdös (1913-1996)
Connect with probability p
Poisson distribution
ARE COMPLEX NETWORKS REALLY RANDOM?
Road and Airline networksPoisson distribution
Exponential Network
Power-law distribution
Scale-free Network
SCIENCE CITATION INDEX
Nodes: papers Links: citations
P(k) ~k-2212
25
Witten-Sander
PRL 1981
SCIENCE COAUTHORSHIP
Nodes: scientist (authors)
Links: write paper together
ACTOR CONNECTIVITIESNodes: actors Links: cast jointly
Days of Thunder (1990) Far and Away
(1992) Eyes Wide Shut (1999)
N = 212,250 actors k = 28.78
P(k) ~k-
=2.3
Rank NameAveragedistance
# ofmovies
# oflinks
1 Rod Steiger 2.537527 112 25622 Donald Pleasence 2.542376 180 28743 Martin Sheen 2.551210 136 35014 Christopher Lee 2.552497 201 29935 Robert Mitchum 2.557181 136 29056 Charlton Heston 2.566284 104 25527 Eddie Albert 2.567036 112 33338 Robert Vaughn 2.570193 126 27619 Donald Sutherland 2.577880 107 2865
10 John Gielgud 2.578980 122 294211 Anthony Quinn 2.579750 146 297812 James Earl Jones 2.584440 112 3787…
876 Kevin Bacon 2.786981 46 1811…
Centrality: Why Kevin Bacon?Measure the average distance between Kevin Bacon and all other actors.
No. of movies : 46 No. of actors : 1811 Average separation: 2.79Kevin Bacon
Is Kevin Bacon the most
connected actor?
NO!
876 Kevin Bacon 2.786981 46 1811
Rod Steiger
Martin Sheen
Donald Pleasence
#1
#2
#3
#876Kevin Bacon
FOOD WEBS
R.J. Williams, N.D. Martinez Nature (2000)
Nodes: trophic species
Links: trophic interactions
SEX WEBS
Nodes: people (Females; Males) Links: sexual relationships