Pérez Roca, CarlosCuesta, José A.Sánchez, Angel2010-03-092010-03-092009-08Europhysics Letters 87, 47005 (2009)0295-5075 (Print)1286-4854 (Online)https://hdl.handle.net/10016/71945 pages, 4 figures.-- PACS nrs.: 87.23.Kg, 02.50.Le, 89.65.-s.-- ArXiv pre-print available at: http://arxiv.org/abs/0905.0869The promotion of cooperation on spatial lattices is an important issue in evolutionary game theory. This effect clearly depends on the update rule: it diminishes with stochastic imitative rules whereas it increases with unconditional imitation. To study the transition between both regimes, we propose a new evolutionary rule, which stochastically combines unconditional imitation with another imitative rule. We find that, surprisingly, in many social dilemmas this rule yields higher cooperative levels than any of the two original ones. This nontrivial effect occurs because the basic rules induce a separation of timescales in the microscopic processes at cluster interfaces. The result is robust in the space of 2×2 symmetric games, on regular lattices and on scale-free networks.application/pdfeng© Europhysics Letters Association (EPLA)[PACS] Dynamics of evolution[PACS] Decision theory and game theory[PACS] Social and economic systemsresearch articleMatemáticas10.1209/0295-5075/87/48005open access