144,460 research outputs found
"Illusion of control" in Minority and Parrondo Games
Human beings like to believe they are in control of their destiny. This
ubiquitous trait seems to increase motivation and persistence, and is probably
evolutionarily adaptive. But how good really is our ability to control? How
successful is our track record in these areas? There is little understanding of
when and under what circumstances we may over-estimate or even lose our ability
to control and optimize outcomes, especially when they are the result of
aggregations of individual optimization processes. Here, we demonstrate
analytically using the theory of Markov Chains and by numerical simulations in
two classes of games, the Minority game and the Parrondo Games, that agents who
optimize their strategy based on past information actually perform worse than
non-optimizing agents. In other words, low-entropy (more informative)
strategies under-perform high-entropy (or random) strategies. This provides a
precise definition of the "illusion of control" in set-ups a priori defined to
emphasize the importance of optimization.Comment: 17 pages, four figures, 1 tabl
The Minority Game Unpacked: Coordination and Competition in a Team-based Experiment
In minority games, players in a group must decide at each round which of two available options to choose, knowing that only subjects who picked the minority op- tion obtain a positive reward. Previous experiments on the minority and similar congestion games have shown that players interacting repeatedly are remarkably able to coordinate eciently, despite not conforming to Nash equilibrium behavior. We conduct an experiment on a minority-of-three game in which each player is a team composed by three subjects. Each team can freely discuss its strategies in the game and decisions must be made via a majority rule. Team discussions are recorded and their content analyzed to detect evidence of strategy co-evolution among teams playing together. Our main results of team discussion analysis show no evidence sup- porting the mixed strategy Nash equilibrium solution, and support a low-rationality, backward-looking approach to model behavior in the game, more consistent with reinforcement learning models than with belief-based models. Showing level-2 ratio- nality (i.e., reasoning about others' beliefs) is positively and signicantly correlated with higher than average earnings in the game, showing that a mildly sophisticated approach pays off. In addition, teams that are more successful tend to become more egocentric over time, paying more attention to their own past successes than to the behavior of other teams. Finally, we nd evidence of mutual adaptation over time, as teams that are more strategic (i.e., they pay more attention to other teams' moves) induce competing teams to be more egocentric instead. Our results contribute to the understanding of coordination dynamics resting on heterogeneity and co-evolution of decision rules rather than on conformity to equilibrium behavior. In addition, they provide support at the decision process level to the validity of modeling behavior using low-rationality reinforcement learning models.coordination, minority game, market eciency, information, self-organization, reinforcement learning s
Statistics of the Kolkata Paise Restaurant Problem
We study the dynamics of a few stochastic learning strategies for the
'Kolkata Paise Restaurant' problem, where N agents choose among N equally
priced but differently ranked restaurants every evening such that each agent
tries get to dinner in the best restaurant (each serving only one customer and
the rest arriving there going without dinner that evening). We consider the
learning strategies to be similar for all the agents and assume that each
follow the same probabilistic or stochastic strategy dependent on the
information of the past successes in the game. We show that some 'naive'
strategies lead to much better utilization of the services than some relatively
'smarter' strategies. We also show that the service utilization fraction as
high as 0.80 can result for a stochastic strategy, where each agent sticks to
his past choice (independent of success achieved or not; with probability
decreasing inversely in the past crowd size). The numerical results for
utilization fraction of the services in some limiting cases are analytically
examined.Comment: 10 pages, 3 figs; accepted in New J Phy
The Minority Game Unpacked: Coordination and Competition in a Team-based Experiment
In minority games, players in a group must decide at each round which of two available options to choose, knowing that only subjects who picked the minority option obtain a positive reward. Previous experiments on the minority and similar congestion games have shown that players interacting repeatedly are remarkably able to coordinate eciently, despite not conforming to Nash equilibrium behavior. We conduct an experiment on a Minority-of-three game in which each player is a team composed by three subjects. Each team can freely discuss its strategies in the game and decisions must be adopted through a majority rule. Team discussions are recorded and their content analyzed to detect evidence of strategy co-evolution between teams playing together. Our main results of group discussion analysis show no evidence supporting the mixed strategy Nash equilibrium solution, suggesting that individuals' non conformity to Nash at the choice data level does not derive from imperfect ability to randomize, but by players intentionally not pursuing this type of strategy. In addition, teams that are more successful tend to be more self-centered over time, paying more attention to their own past successful strategies than to the behavior of other teams. Moreover, we nd evidence of mutual adaptation between players' strategies, as teams that are more sophisticated (i.e., they pay more attention to other teams' moves) tend, on average, to induce other teams to be less sophisticated and more self-centered. Our results contribute to the understanding of coordination dynamics resting on heterogeneity and co-evolution of decision rules rather than on conformity to equilibrium behavior, both at the aggregate and at the individual level.
The minority game: An economics perspective
This paper gives a critical account of the minority game literature. The
minority game is a simple congestion game: players need to choose between two
options, and those who have selected the option chosen by the minority win. The
learning model proposed in this literature seems to differ markedly from the
learning models commonly used in economics. We relate the learning model from
the minority game literature to standard game-theoretic learning models, and
show that in fact it shares many features with these models. However, the
predictions of the learning model differ considerably from the predictions of
most other learning models. We discuss the main predictions of the learning
model proposed in the minority game literature, and compare these to
experimental findings on congestion games.Comment: 30 pages, 4 figure
Multi-Choice Minority Game
The generalization of the problem of adaptive competition, known as the
minority game, to the case of possible choices for each player is
addressed, and applied to a system of interacting perceptrons with input and
output units of the type of -states Potts-spins. An optimal solution of this
minority game as well as the dynamic evolution of the adaptive strategies of
the players are solved analytically for a general and compared with
numerical simulations.Comment: 5 pages, 2 figures, reorganized and clarifie
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