@masterthesis { vasconcelos12, abstract = {Preventing global warming requires overall cooperation. Contributions will depend on the risk of future losses, which plays a key role in decision making. Here, I discuss an evolutionary game theoretical model in which decisions within small groups under high risk and stringent requirements toward success significantly raise the chances of coordinating to save the planet’s climate, thus escaping the tragedy of the commons. I analyze both deterministic dynamics in infinite populations, and stochastic dynamics in finite populations. I also study the impact of different types of sanctioning mechanisms in deterring non-cooperative behavior in climate negotiations, towards the mitigation of the effects of climate change. To this end, I introduce punishment in the collective-risk dilemma and study the dynamics of collective action in finite populations. I show that a significant increase in cooperation is attained whenever individuals have the opportunity to contribute (or not) to institutions that punish free riders. I investigate the impact of having local instead of global sanctioning institutions, showing that the former – which are expected to require less financial resources and which involve agreements between a smaller number of individuals – are more conducive to the prevalence of an overall cooperative behavior. In the optics of evolutionary game theory, the system dynamics is solved by means of a multidimensional stochastic Markov process. The interaction between individuals is not pairwise but it occurs in n-person games; the individuals have perception of the risk and are allowed to explore unpopulated strategies.}, address = {Campo Grande, 1749-016 Lisboa}, keywords = {Miscellaneous;Game Theory;Multi-Agent Societies;}, month = {July}, school = {Faculdade de Ciências da Universidade de Lisboa}, title = {The Role of Sanctioning in the Evolutionary Dynamics of Collective Action}, year = {2012}, author = {Vítor V. Vasconcelos} }