Coordination game in bidirectional flow

We have introduced evolutionary game dynamics to a one-dimensional cellular-automaton to investigate evolution and maintenance of cooperative avoiding behavior of self-driven particles in bidirectional flow. In our model, there are two kinds of particles, which are right-going particles and left-going particles. They often face opponent particles, so that they swerve to the right or left stochastically in order to avoid conflicts. The particles reinforce their preferences of the swerving direction after their successful avoidance. The preference is also weakened by memory-loss effect. Result of our simulation indicates that cooperative avoiding behavior is achieved, i.e., swerving directions of the particles are unified, when the density of particles is close to 1/2 and the memory-loss rate is small. Furthermore, when the right-going particles occupy the majority of the system, we observe that their flow increases when the number of left-going particles, which prevent the smooth movement of right-going particles, becomes large. It is also investigated that the critical memory-loss rate of the cooperative avoiding behavior strongly depends on the size of the system. Small system can prolong the cooperative avoiding behavior in wider range of memory-loss rate than large system

What are GPs' preferences for financial and non-financial incentives in cancer screening? Evidence for breast, cervical, and colorectal cancers

We benefited for this research from grants provided by the French National Institute for Cancer (INCa) (INCA_7014). We would like to thank Dr Diane Skatun, Mary Kilonzo, and the three anonymous reviewers for their useful comments on the paper.Peer reviewedPostprin

Company tax coordination cum tax rate competition in the European Union

This paper reviews the recent theoretical literature that analyses the European Union's policy to eliminate preferential corporate tax regimes and the proposal to introduce a consolidated EU tax base with formula apportionment for the taxation of multinational firms. Since neither proposal includes a harmonisation of corporate tax rates, a core issue is how tax competition between member states will be affected by these partial coordination measures. The conclusions from our review are supportive of the EU's ban on preferential tax regimes, but the economic incentive effects of a switch to formula apportionment are found to be ambiguous

THE ROLE OF NETWORKS IN COLLECTIVE ACTION WITH COSTLY COMMUNICATION.

Individuals frequently contribute their resources voluntarily to provide public goods. This paper models the manner in which the linkage between members in a community influences the likelihood of such actions through spontaneous activism in networks. The model I use abstracts from the issue of free-riding behavior by means of small deviations from standard preferences. Instead, it concentrates on the communication aspect of provision through collective action. The solution concept is Nash equilibrium. I find that the likelihood of efficient provision of a discrete public good in random social networks increases very rapidly for parameter values where the network experiences a phase transition and large-scale decentralized activism becomes feasible. As a result, the model shows that successful coordination may be more readily achieved the larger the population is, provided its members are sufficiently connected. In contrast with previous results in the literature, this results holds even as the size of the population increases without bound, and it is consistent with the existence of largescale activism in large populations.Collective Action

Efficient Equilibria in Polymatrix Coordination Games

We consider polymatrix coordination games with individual preferences where every player corresponds to a node in a graph who plays with each neighbor a separate bimatrix game with non-negative symmetric payoffs. In this paper, we study $\alpha$-approximate $k$-equilibria of these games, i.e., outcomes where no group of at most $k$ players can deviate such that each member increases his payoff by at least a factor $\alpha$. We prove that for $\alpha \ge 2$ these games have the finite coalitional improvement property (and thus $\alpha$-approximate $k$-equilibria exist), while for $\alpha < 2$ this property does not hold. Further, we derive an almost tight bound of $2\alpha(n-1)/(k-1)$ on the price of anarchy, where $n$ is the number of players; in particular, it scales from unbounded for pure Nash equilibria ($k = 1)$ to $2\alpha$ for strong equilibria ($k = n$). We also settle the complexity of several problems related to the verification and existence of these equilibria. Finally, we investigate natural means to reduce the inefficiency of Nash equilibria. Most promisingly, we show that by fixing the strategies of $k$ players the price of anarchy can be reduced to $n/k$ (and this bound is tight)