simulating the social processes of science leiden| 9 april 2014
DESCRIPTION
www.ingenio.upv.es. Simulating the Social Processes of Science Leiden| 9 April 2014. DIFFUSION OF SCIENTIFIC KNOWLEDGE: A PERCOLATION MODEL Elena M. Tur With P Zeppini and K Frenken. INGENIO [CSIC-UPV] Ciudad Politécnica de la Innovación | Edif 8E 4º Camino de Vera s/n - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/1.jpg)
Simulating the Social Processes of Science Leiden| 9 April 2014
INGENIO [CSIC-UPV] Ciudad Politécnica de la Innovación | Edif 8E 4º Camino de Vera s/n 46022 Valencia
tel +34 963 877 048 fax +34 963 877 991
DIFFUSION OF SCIENTIFIC KNOWLEDGE:
A PERCOLATION MODEL
Elena M. Tur
With P Zeppini and K Frenken
www.ingenio.upv.es
![Page 2: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/2.jpg)
2
• How do social pressure and assortativity affect the process of diffusion?
• How do their effect interact with the social network structure?
• How do local effects dictate global diffusion through the overall network structure?
• Main contribution: introducing social pressure in a model of diffusion with different network structures
Focus
2
![Page 3: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/3.jpg)
3
• Spread of rumors (Zanette, 2002)• Online spreading of behavior (Centola, 2010)• Opinion dynamics (Shao et al., 2009)• Paradigm shift in science (Brock and Durlauf, 1999)
• How to approach the problem (Zeppini and Frenken, 2013)• Heterogeneity of agents• Externalities• Social network• Percolation (Solomon et al., 2000)
Diffusion of ideas
![Page 4: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/4.jpg)
4
• : value of the idea• : minimum quality requirement of agent
Agent adopts the idea at time if:• has not adopted before • is informed: a neighbor has adopted at time • is willing to adopt:
Percolation in a social network
![Page 5: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/5.jpg)
5
Percolation in a social network
𝑞𝑖∼𝑈 [0,1 ]→𝑞𝑖≤𝑣0?
![Page 6: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/6.jpg)
6
Percolation in a social network
![Page 7: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/7.jpg)
7
• Small world (Watts and Strogatz, 1998)Starting with a regular lattice, with nodes and 𝑛 𝑘edges per node, rewire each edge at random with probability 𝑝
• High clustering coefficient, low average path length
Social network
![Page 8: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/8.jpg)
8
• Upper bound to diffusion: 45º line (well-mixed population)
• Diffusion increases with • Phase changes: from a
non-diffusion to a diffusion regime
• Percolation thresholds decrease with
Percolation without social pressure
![Page 9: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/9.jpg)
9
SOCIAL PRESSURE
![Page 10: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/10.jpg)
10
• The unwilling to adopt can be persuaded • Network externalities: shared language, shared
experiences, shared beliefs…• Increasing amount of evidence• Conformity (Asch,1958)
• Weariness
Why social pressure?
![Page 11: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/11.jpg)
11
• : # neighbors of agent that have adopted at time • : social pressure intensity
• is decreasing in the number of adopting neighbors • is decreasing in the social pressure intensity• if • if
Modelling social Pressure
![Page 12: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/12.jpg)
12
• agents• original neighbors in the small world algorithm• seeds or original adopters• time periods• runs of Monte Carlo simulations
• iid• Social networks: lattice, small world, Poisson network
Parameters for the simulations
12
![Page 13: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/13.jpg)
13
Percolation with social pressure
![Page 14: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/14.jpg)
14
Clustering with social pressure
![Page 15: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/15.jpg)
16
ASSORTATIVITY People tend to be friends with similar people
![Page 16: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/16.jpg)
17
Modelling assortativity
Most unwilling to adopt
Most willing to adopt
![Page 17: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/17.jpg)
18
• No critical transition from non-diffusion to diffusion
• Diffusion size scales linearly with diffusion size
• No effect of the network structure (well-mixed population)
Percolation with assortativity
![Page 18: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/18.jpg)
19
Percolation with social pressure and assortativity
![Page 19: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/19.jpg)
20
Does assortativity help diffusion?
![Page 20: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/20.jpg)
21
Does assortativity help diffusion? (2)
![Page 21: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/21.jpg)
22
CONCLUSIONS
![Page 22: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/22.jpg)
23
• Social pressure changes the behavior of the percolation process: higher diffusion size, lower percolation thresholds
• The effect of social pressure is different for different network structures: critical transition in small worlds and lattices
• With social pressure, clustering becomes beneficial for diffusion: reduced differences between networks
• Assortativity removes the effect of the network structure: all behave as a well-mixed population
• Assortativity can help or hamper diffusion depending on the setting
Conclusions
![Page 23: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/23.jpg)
24
• Other social network structures: scale-free networks (Barábasi and Albert, 1999)
• Evolving endogenous social network• Re-think the social pressure implementation: always
possitive efffect?• Different minimum quality requirement distributions,
Future work and limitations
![Page 24: Simulating the Social Processes of Science Leiden| 9 April 2014](https://reader035.vdocuments.us/reader035/viewer/2022081511/56816147550346895dd0c4ad/html5/thumbnails/24.jpg)
25
THANK YOUINGENIO [CSIC-UPV] Ciudad Politécnica de la Innovación | Edif 8E 4º Camino de Vera s/n 46022 Valencia
tel +34 963 877 048 fax +34 963 877 991