Win Stay, Lose Shift as well as imitation strategies for iterated games rely on an aspiration level. With both learning rules a move is repeated unless the pay-o fell short of the aspiration level. I investigate social adaptation mechanisms for the aspiration level and their impact on the eÆciency of learning in a large population of agents that repeatedly play one round of a symmetric 2 2 game...

We use replicator dynamics to study an iterated prisoners’ dilemma game with memory. In this study, we investigate the characteristics of all 32 possible strategies with a single-step memory by observing the results when each strategy encounters another one. Based on these results, we define similarity measures between the 32 strategies and perform a network analysis of the relationship between...

Chepoi showed that every breadth /rst search of a bridged graph produces a cop-win ordering of the graph. We note here that Chepoi’s proof gives a simple proof of the theorem that G is bridged if and only if G is cop-win and has no induced cycle of length four or /ve, and that this characterization together with Chepoi’s proof reduces the time complexity of bridged graph recognition. Speci/call...

Cannabinoids can evoke antihyperalgesia and antinociception at a peripheral site of action. However, the signaling pathways mediating these effects are not clearly understood. We tested the hypothesis that certain cannabinoids directly inhibit peripheral capsaicin-sensitive nociceptive neurons by dephosphorylating and desensitizing transient receptor potential vanilloid 1 (TRPV1) via a calcium ...