Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

AKSOE: Arbeitskreis Physik sozio-ökonomischer Systeme

AKSOE 13: Poster Session (posters on display 10:00-19:00)

AKSOE 13.2: Poster

Mittwoch, 27. Februar 2008, 17:30–19:00, Poster G

Learning, evolution and population dynamics — Juergen Jost and •Wei Li — MPIMIS, Inselstr. 22, 04103 Leipzig

We study a complementarity game as a systematic tool for the investigation of the interplay between individual optimization and population effects and for the comparison of different strategy and learning schemes. The game randomly pairs players from opposite populations (buyers and sellers), with each independently making an offer between 0 and K. When the buyer's offer k(b) is no less than the seller's offer k(s), a deal is done and the buyer wins K-k(b) and the seller k(s); otherwise the interaction fails and both gain nothing. The game is symmetric at the individual level, but has many equilibria that are more or less favorable to the members of the two populations. Which of these equilibria then is attained is decided by the dynamics at the population level. Players play repeatedly, but in each round with a new opponent. They can learn from their previous encounters and translate this into their actions in the present round on the basis of strategic schemes. The schemes can be quite simple, or very elaborate. We can then break the symmetry in the game and give the members of the two populations access to different strategy spaces. Typically, simpler strategy types have an advantage because they tend to go more quickly towards a favorable equilibrium which, once reached, the other population is forced to accept. Also, populations with bolder individuals that may not fare so well at the level of individual performance may obtain an advantage towards ones with more timid players.