Abstract
This chapter extends the DeGroot–Friedkin model by introducing dynamic network topology, and in particular, issue-varying relative interaction topology (the term “issue” is used interchangeably with “topic”). The dynamic network topology problem is formally defined, with motivating examples provided as to why issue-varying networks are reflective of real-world social networks. Then, the nonlinear contraction analysis framework introduced in Chap. 5 is used to draw a key conclusion: under mild assumptions on the properties of the issue-varying network, each individual’s initial (perceived) social power is forgotten exponentially fast, and in the limit of the issue sequence, each individual’s social power converges to a “unique limiting trajectory” that depends only on the issue-varying network topology. The results in Sect. 5.3 concerning the upper bound on an individual’s social power at equilibrium and convergence rate for a class of topologies are also extended, with obvious modifications due to the dynamic topology. As a special case, periodically-varying topologies are also considered.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
- 2.
The sets \(\varDelta _n\), \(\widetilde{\varDelta }_n\), and \(\text {int}(\varDelta _n)\) were defined in Sect. 2.1, and are now redefined for the reader’s convenience: The n-simplex is \(\varDelta _n = \{\varvec{x}\in \mathbb {R}^n : 0 \le \varvec{x}, \varvec{1}_n^\top \varvec{x} = 1 \}\), and \(\widetilde{\varDelta }_n = \varDelta _n \backslash \{ \mathbf {e}_1, \ldots , \mathbf {e}_n \}\) and \(\text {int}(\varDelta _n) = \{\varvec{x}\in \mathbb {R}^n : 0 < \varvec{x}, \varvec{1}_n^\top \varvec{x} = 1 \}\).
- 3.
A well-known set is \(\mathcal {K}(\varvec{1}_n/n)\), the set of \(n\times n\) doubly-stochastic \(\varvec{C}\).
- 4.
Any given \(s\in \mathcal {S}\) can be uniquely expressed by a given fixed positive integer P, a nonnegative integer q, and positive \(p\in \mathcal {P}\), as shown.
- 5.
During the thesis examination process, an examiner has identified an alternative proof, which we summarise here for the interested reader. The existence of \(\varvec{x}^*(s)\) was established in Theorem 6.1. Since \(\varvec{x}(2s+2)\) is also a trajectory, \(\Vert \varvec{x}^*(2s+2) - \varvec{x}^*(2s)\Vert \) converges to 0 exponentially fast. From this, one has that for any \(s \ge 0\) and \(k \in \mathbb {N}\), \(\Vert \varvec{x}^*(s+2k) - \varvec{x}(2s) \Vert \) converges to 0 exponentially fast; that is \(\varvec{x}^*(2s)\) is a Cauchy sequence in \(\bar{\mathcal {A}}\), which must converge to a point, denoted as \(\varvec{z}_1^*\). From Eq. (6.14), and by continuity, \(\varvec{z}_1^*\) must be a fixed point of \(\varvec{F}_1(\varvec{F}_2(.))\). A similar approach shows that \(\varvec{x}^*(2s+1)\) must converge to a point, \(\varvec{z}_2^*\), which must be a fixed point of \(\varvec{F}_2(\varvec{F}_1(.))\).
- 6.
The initial condition vector \(\widehat{\varvec{x}}(0)\) also illustrates the relaxed initial condition assumption.
References
Amelkin V, Bullo F, Singh AK (2017) Polar opinion dynamics in social networks. IEEE Trans Autom Control 62:5650–5665
Anderson BDO, Shi G, Trumpf J (2017) Convergence and state reconstruction of time-varying multi-agent systems from complete observability theory. IEEE Trans Autom Control 62:2519–2523
Anderson BDO, Ye M (in press) Recent advances in the modelling and analysis of opinion dynamics on influence networks. Int J Autom Comput
Cao M, Morse AS, Anderson BDO (2008) Reaching a consensus in a dynamically changing environment: a graphical approach. SIAM J Control Optim 47:575–600
Dandekar P, Goel A, Lee DT (2013) Biased assimilation, homophily, and the dynamics of polarization. Proc Natl Acad Sci 110:5791–5796
Duggins P (2017) A psychologically-motivated model of opinion change with applications to American politics. J Artif Soc Soc Simul 20:1–13
Jadbabaie A, Lin J, Morse AS (2003) Coordination of groups of mobile autonomous agents using nearest neighbor rules. IEEE Trans Autom Control 48:988–1001
Jia P, MirTabatabaei A, Friedkin NE, Bullo F (2015) Opinion dynamics and the evolution of social power in influence networks. SIAM Rev 57:367–397
Liu J, Chen X, Başar T, Belabbas MA (2017) Exponential convergence of the discrete- and continuous-time Altafini models. IEEE Trans Autom Control 62:6168–6182
Mäs M, Flache A, Kitts JA (2014) Cultural integration and differentiation in groups and organizations. Perspectives on Culture and Agent-Based Simulations. Springer, Berlin, pp 71–90
Mesbahi M, Egerstedt M (2010) Graph Theoretic Methods in Multiagent Networks. Princeton University Press, Princeton
Nedić A, Liu J (2017) On convergence rate of weighted-averaging dynamics for consensus problems. IEEE Trans Autom Control 62:766–781
Proskurnikov A, Matveev A, Cao M (2016) Opinion dynamics in social networks with hostile camps: consensus versus polarization. IEEE Trans Autom Control 61:1524–1536
Ren W, Beard R (2007) Distributed Consensus in Multi-Vehicle Cooperative Control: Theory and Applications. Springer, London
Ren W, Beard RW (2005) Consensus seeking in multiagent systems under dynamically changing interaction topologies. IEEE Trans Autom Control 50:655–661
Shi G, Johansson KH (2013) The role of persistent graphs in the agreement seeking of social networks. IEEE J Sel Areas Commun 31:595–606
Ye M, Liu J, Anderson BDO, Yu C, Basar T (2018) Evolution of social power in social networks with dynamic topology. In: IEEE transactions on automatic control. 63(11):3793–3808, November 2018
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this chapter
Cite this chapter
Ye, M. (2019). Dynamic Social Networks: Exponential Forgetting of Perceived Social Power. In: Opinion Dynamics and the Evolution of Social Power in Social Networks. Springer Theses. Springer, Cham. https://doi.org/10.1007/978-3-030-10606-5_6
Download citation
DOI: https://doi.org/10.1007/978-3-030-10606-5_6
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-10605-8
Online ISBN: 978-3-030-10606-5
eBook Packages: Intelligent Technologies and RoboticsIntelligent Technologies and Robotics (R0)