The Coauthored Paper of Professor Cao Zhigang from School of Economics and Management was published on the famous International Journal of Game Theory

The paper Dynamic Matching Pennies on Networks, cooperated by Professor Cao Zhigang of our school, Professor Qin Chengzhong of UCSB (the University of California, Santa Barbara ), researcher Yang Xiaoguang of the Academy of Mathematics and Systems Science of the Chinese Academy of Sciences and Associate Professor Zhang Boyu of Beijing Normal University, was published on the International Journal of Game Theory, a famous journal in the field of game theory. The original version of the paper was completed in May 2013, six years later, it was finally officially accepted in 2019.

The paper investigated the simultaneous best response dynamic focusing on the lengths of limit cycles (LLC) , which is a generalization of Nash equilibrium, because LLC="1" means that the corresponding strategy combination must be a pure strategy Nash equilibrium.

By constructing a Lyapunov function, Professor Cao Zhigang and his collaborators proved that LLC="1" or 2 when all the agents are of the same (that is, either all agents are cooperators or all agents are anti-cooperators). They then considered three special types of network structures, namely linear networks, ring networks and star networks. In the linear networks and the ring networks, they found that the initial value in almost all cases would lead LLC="1;" In the star networks, the initial value in half of the cases would cause LLC="4. 

The paper was considered by the Associate Editor of the International Journal of Game Theory to study as an ¡°extremely important¡± topic that has not been satisfactorily studied in the literature. He said, ¡°I believe the topic you study ¡ªthe simultaneous play of different games on a given network ¡ªis extremely important and has not been dealt with satisfactorily in the literature.¡± The International Journal of Game Theory is the flagship journal of the International Game Theory Society and is one of the most important landmark journals in the field of game theory, which was founded in 1971 by Professor Aumann, the Nobel Prize winner in economics. It is quite difficult to publish paper on it. The papers published by scholars in Chinese mainland on this journal each year can be counted by bending the fingers ( three papers was published in 2019).

The Paper£ºZhigang Cao, Chengzhong Qin, Xiaoguang Yang, Boyu Zhang, 2019, Dynamic matching pennies on networks, International Journal of Game Theory, 48: 887-920.