Slides for Roca, Cuesta & Sanchez’s EGT: Temporal and spatial effects beyond replicator dynamics

Last Wednesday, October 10th, 2012 we discussed Roca, Cuesta & Sanchez (2009) Evolutionary games theory: Temporal and spatial effects beyond replicator dynamics. The hope was to have a review as amazing as Szabo & Fath (2007), and we divided the work in a similar way.

  • Thomas Shultz presented Section 2: Basic concepts and results of evolutionary game theory.
  • Marcel Montrey presented Section 4: Structured populations.

I covered section 3 (The effects of different time scales) but without slides; I am still a fan of the blackboard. Tom’s slides provide an exposition of the basic model of the replicator equation, and closely follow Nowak’s Evolutionary Dynamics. I recommend these slides if you need a quick reminder. Unfortunately, the rest of the paper did not build on the equation (as you would expect from title) but provided (mostly) simulation based alternatives. Section 3 discussed the observation that having a different number of interactions per generation sets the speed of evolution. Evolution is fast is there are few interactions per generation, and slow otherwise. Fast evolution leads to more noise in the population, making it harder to stay in shallow optima. Unfortunately, they do not present cases where this results in a change of optima, like the low pairings we saw in Riolo, Cohen & Axelrod (2001). In his slides, Marcel does a great job of stressing the key insight RCS09 provide in section 4: the importance of update rules. The authors focus exclusively on simulation work, and point out the inconsistencies that can arise from seemingly minor changes in update rules. For the rest of the discussion of spatial structure, they do not go beyond Szabo & Fath and Marcel’s spatial structure post.

In all honesty, I was expecting a more analytic treatment from this Physics of Life Review, and was disappointed about the disconnect from the greatest strength of replicator dynamics: the intuitiveness of an analytic toolkit. Carlos P. Roca, José A. Cuesta, & Angel Sánchez (2009). Evolutionary game theory: Temporal and spatial effects beyond replicator dynamics Physics of Life Reviews, 6, 208-249 arXiv: 0911.1720v1