Volume 85, Number 4, February 2009
Article Number 48003
Number of page(s) 6
Section Interdisciplinary Physics and Related Areas of Science and Technology
Published online 09 March 2009
EPL, 85 (2009) 48003
DOI: 10.1209/0295-5075/85/48003

Dynamics of strategic three-choice voting

D. Volovik1, M. Mobilia2, 3 and S. Redner1

1   Center for Polymer Studies and Department of Physics, Boston University - Boston, MA 02215, USA
2   Department of Applied Mathematics, School of Mathematics, University of Leeds - Leeds LS2 9JT, UK, EU
3   Mathematics Institute & Warwick Centre for Complexity Science, The University of Warwick Coventry CV4 7AL, UK, EU

received 9 December 2008; accepted in final form 6 February 2009; published February 2009
published online 9 March 2009

In certain parliamentary democracies, there are two major parties that move in and out of power every few elections, and a third minority party that essentially never governs. We present a simple model to account for this phenomenon, in which minority party supporters sometimes vote ideologically (for their party) and sometimes strategically (against the party they like the least). The competition between these disparate tendencies reproduces the empirical observation of two parties that frequently exchange majority status and a third party that is almost always in the minority.

89.75.Fb - Structures and organization in complex systems.
02.50.-r - Probability theory, stochastic processes, and statistics.

© EPLA 2009