%0 Generic %A Dokumaci, E. %A Lahkar, R. %A Sandholm, W.H. %C London, UK %D 2007 %F discovery:14428 %I ESRC Centre for Economic Learning and Social Evolution %N 271 %T The projection dynamic, the replicator dynamic and the geometry of population games %U https://discovery.ucl.ac.uk/id/eprint/14428/ %X Every population game defines a vector field on the set of strategy distributions X. The projection dynamic maps each population game to a new vector field: namely, the one closest to the payoff vector field among those that never point outward from X. We investigate the geometric underpinnings of the projection dynamic, describe its basic game-theoretic properties, and establish a number of close connections between the projection dynamic and the replicator dynamic.