Papers


So far, there are 158 papers listed here. If one of yours is missing here, please email me !


Articles related to the standard Minority Game :

By "standard", I mean Minority Game as first defined: global game, N agents, S strategies, virtual points [inductive agents], global game, global history.



The original paper:

  • D. Challet and Y.-C. Zhang, Emergence of Cooperation and Organization in an Evolutionary Game, Physica A 246, 407 (1997), preprint


An easy-to-read introduction to the MG:

  • Y.-C. Zhang, Modeling Market Mechanism with Evolutionary Games, Europhys. News 29, 51 (1998), preprint


Numerical evidence that all the interesting quantities only depend on P/N (P=2M). First mention of the existence of a phase transition and first evidence of the presence of "information" in the "non-crowded" region:

  • R. Savit et al., Adaptive Competition, Market Efficiency, Phase Transitions and Spin-Glasses (1997), preprint

  • R. Savit et al., Adaptive Competition, Market Efficiency, Phase Transition, PRL, 82(10), 2203 (1999) (a more attractive version of the above preprint)

A more complete and precise version of their previous paper ; extensive numerical results with qualitative explanations, analytical approach valid for P/N<<1.

  • R. Manuca et al., The Structure of Adaptative Competition in Minority Games (1998), preprint


Numerical study of the variance in the MG and in the Bar Problem (BP). The variance of the BP has also a minimum:

  • N. F. Johnson et al., Volatility and Agent Adaptability in a Self Organizing Market, Physica A, 256, 230 (1998), preprint


Numerical evidence that the variance does not depend on the dynamics of the histories in the symmetric region (Note from me: this is not true in the asymmetric phase. See herefor more details)

  • A. Cavagna, Irrelevance of Memory in the Minority Game, PRE (1998), preprint

  • A. Cavagna, Comment on "Adaptive Competition, Market Efficiency, and Phase Transitions", Phys. Rev. Lett. 84 5, 1058 (2000)

  • R. Savit, Reply to Comment on "Adaptive Competition, Market Efficiency, and Phase Transitions"Phys. Rev. Lett. 84, 1059 (2000)

A response: the temporal correlation are relevant in the MG for instance in a population with various M is considered.

  • N. F. Johnson et al., Enhanced winnings in a mixed ability population playing a minority game, (1999)  preprint

Self-consistent solution of MG with real histories; the dynamics of histories is non trivial and relevant in most cases. Only in the symmetric phase of the standard MG it is not, at least for the fluctuations.

  • D. Challet and M. Marsili, Relevance of Memory in Minority Games, (2000) preprint


Extensive numerical study of the symmetric phase and introduction of the majority model:

  • M. A. R. de Cara et al., Competition, efficiency and collective behavior in the "El Farol" bar problem (1998), preprint


Introduction of the distance between players and the reduced strategy space, study of Darwinism effects, resource sharing, variance of the attendance, mixed memory population:

  • D. Challet and Y.-C. Zhang, On the Minority Game: Analytical and Numerical Studies, Physica A 256, 514  (1998), preprint


A study of the Chaitin algorithmic complexity of the minority sign, as well as the mutual information. In this preprint, N=201:

  • R. Mansilla, Algorithmic Complexity in the Minority Game (1999), preprint


Intuitive analytical study of the variance of the attendance for the MG in the reduced strategy space and for the BP:

  • N. F. Johnson et al., Crowds Effects and Volatility in a Competitive Market (1998) preprint


Details of the previous paper:

  • M. Hart, P. Jefferies, N. F. Johnson and P. M. Hui, Crowd-Anticrowd model of the Minority Game (2000), preprint

  • M. Hart, P. Jefferies, N. F. Johnson and P. M. Hui, Crowd-anticrowd theory of the Minority Game (2000), preprint

  • M. Hart, P. Jefferies, P.M. Hui, N.F. Johnson, Crowd-Anticrowd Theory of Multi-Agent Market Games (2000), preprint

A try to apply to the original MG the method introduced in the previous preprint of N. F. Johnson  et al.:

  • R. D'hulst, G. J. Rodgers, The Hamming Distance in the Minority Game (1999), preprint


Tries to understand the dynamics of a modified MG, in the crowded region, by ergordic invariants:

  • R. Vilela Mendes, Characterizing Self-Organization and Coevolution by Ergodic Invariants (1999), preprint


An adequate mathematical formalism is introduced. Formal connection between the MG and neural networks spin-glasses, finite size determination of the critical point, caracterization of the symmetry breaking and the two phases. Shows that the cause of cooperation is caused by the deterministic behavior of some agents for some histories: if agents have two opposite strategies, no cooperation arises:

  • D. Challet and M. Marsili, Symmetry Breaking and Phase Transition in the Minority Game (1999),  preprint


A continuous MG (or mixed histories MG ?) ; introduction of exponential learning (Bolzman weights, Logit model) in the use of the strategies. The "temperature" reduces the fluctuations in the symmetric phase, and turns out to be a time scale, or a learning rate in the asymmetric phase. This model is statistically equivalent to MG with binary strategies, hence all exact results for the standard MG with "temperature" hold.

  • A. Cavagna, J.P. Garrahan, I. Giardina and D. Sherrington, A Thermal Model for Adaptive Competition in a Market, , Phys. Rev. Lett. 83, 4429 (1999). preprint

  • D. Challet, M. Marsili and R. Zecchina, Comment on "A Thermal Model for Adaptive Competition in a Market", submitted (2000), preprint

  • A. Cavagna, J.P. Garrahan, I. Giardina and D. Sherrington, Reply to Comment on ``Thermal Model for Adaptive Competition in a Market'', preprint


First numerical evidence that the temperature of the above model is a learning rate, that is, a time scale. Also shows that the number of visited histories decreases when P/N increases in the asymmetric phase (finite size effect):

  • G. Bottazzi, G. Devetag G. Dosi (SASAS Pisa, Italy), Learning and Emergent Coordination in Speculative Markets: Some Properties of "Minority Game" Dynamics, preprint (1999)


Exact solution to the asymmetric phase for S=2 (agents minimize available information), and of the symmetric for large enough "temperature". Introduction of a corrected inductive dynamics (the agents know their impact on the "market") leading to a Nash equilibrium (minimization of the fluctuations). See cond-mat/9909265 for detailed symmetric replica calculus and cond-mat/0007397 for the symmetry broken replica calculus.

  • D. Challet, M. Marsili and R. Zecchina, Statistical Mechanics of Heterogeneous Agents (1999), preprint

A generalisation of the previous preprint to any S. This preprint is written in the language of economists.

  • M. Marsili, D. Challet and R. Zecchina, Exact Solution of a Modified El Farol's Bar Problem (1999), preprint

Short review of the two previous works

  • D. Challet, M. Marsili and R. Zecchina, Phase Transition in a Toy market (1999), psfile

Review aiming at describing the state of art in econophysics; has a section about the MG:

  • J. D. Farmer, Physicists Attempt to Scale the Ivory Tower of Finance (1999), preprint


Analytical approach for the symmetric phase that gives good results for very small P/N:

  • R. D'hulst, G. J. Rodgers and M. Ausloss, Strategy Selection in the Minority Game(1999), Physica A 278, 579 (2000), preprint


Numerical evidence that the phase transition is robust under the change of payoff:

  • Y. Li, A. VanDeeme, R. Savit, The Minority Game with Variable Payoffs (2000), preprint


A study of the Chaitin algorithmic complexity of the minority sign, as well as the mutual information for the corrected dynamics with continuous parameter:

  • R. Mansilla, From Naive to Sophisticated Behaviour in Multi agents Based Financial Market Models (2000), preprint


Aims to study continuous (non rescaled) time in the MG. Also recovers results of spin-glass nature of MG found in preprints cond-mat/9904392, 9908480, and 0004308. Shows numerically that in anti-persistent regions, the system's state depends on the initial condition (see preprint cond-mat/0102257 for another discussion about stochastic continuous time equations).

  • Juan P. Garrahan, Esteban Moro, David Sherrington, Continuous time dynamics of the Thermal Minority Game (2000), preprint

  • David Sherrington, Juan P. Garrahan, Esteban Moro, Statistical Physics of Adaptive Correlation of Agents in a Market (2000), preprint

Shows analytically that antipersistent behaviour is caused by neglect of market impact and fast learning rate. This happens for P/N small and small enough "temperature". Exact solution for all parameters of MG with no memory. Shows analytically that in anti-persistent regions, the system's state depends on the initial condition. Derive a critical "temperature":

  • M. Marsili, D. Challet, Trading behaviour and excess volatility in toy markets (2000), preprint

Extends and completes the analytic solution of MG where agents take into account their impact on the game, by doing a 1-step replica symmetry broken calculus:

  • Andrea De Martino, Matteo Marsili, Replica symmetry breaking in the minority game (2000), preprint

Uses exact generating functional techniques a la De Dominicis for a modified MG, which seems to be essentially the same as the original MG; shows how to obtain in principle the exact dynamical solution of the MG in thermodynamic limit. Not only recovers the replica results for the asymmetric phase, but also allows for the first time to address the dynamics of the symmetric phase in anti-persistent regions, i.e. for small T. Able to deal with non-zero initial strategy scores:

  • J. A. F. Heimel, A. C. C. Coolen, Generating Functional Analysis of the Dynamics of the Batch Minority Game with Random External Information (2000), preprint

Temporal properties of the symmetric phase are investigated numerically:

  • D. Zheng , B.-H. Wang, Statistical Properties of the Attendance Time Series in the Minority Game (2001), preprint

Sorts out the question of the continuous time limit. Derives stochastic equation in continuous (rescaled) time, which are valid for all parameters of the game; the obtained Fokker-Planck equation is solved. Shows that i) the "temperature" T or learning rate of agents is actually an inverse temperature for the system; ii) only in the limit of infinite "temperature" (i.e. zero), there is a Lyapunov function; iii) for all parameters, the stationary/steady state really corresponds to the minimum of the available information, hence the replica calculus is exact whenever a stationary state is reached; iv) the replica calculus can account for non uniform initial condition in the symmetric phase; v) explains why only the symmetric phase is sensitive to learning rates and to initial conditions v) gives a self-consistent equation for sigma that is also valid for the symmetric phase vi) gives the Hamiltonian for any payoff.

  • M. Marsili, D. Challet, On the continuous time limit and stationary states of the Minority Game (2001), preprint

Strategies' scores are kept only during a small time window of T time steps. Exact results for the fluctuations, for a given realisation of the disorder.

  • M. L. Hart, P. Jefferies, N. F. Johnson, Dynamics of the Time Horizon Minority Game (2001), preprint

Studies the MG where no coin-tossing takes place when two strategies have the same score. Able to produce approximate analytical expressions and to provide an intuitive interpretation of various phenomena in term of a restoring force and a bias.

  • P. Jefferies, M.L. Hart, N.F. Johnson, Deterministic Dynamics in the Minority Game (2001), preprint

Introduces a finite memory in the scores of strategies (see also cond-mat/0102257) and finds a phase transition between presence and absence of coordination when the ratio of the learning rate to the oblivion rate is varied (analytical results). Introduces also a new evolving scheme where all the predictions of all strategies of all agents are changed for one piece of information.

  • M. Marsili, R. Mulet, F. Ricci-Tersenghi and R. Zecchina, Learning to Coordinate in a Complex and Non-Stationary World, preprint

Shows that in the symmetric phase, the period two process disappears if random histories are considered

  • Ch.-Y. Lee, Is Memory in the Minority Game Relevant?, PRE 64,015105R (2001)

Exact analytical results for MGs with exponential learning and noise not only on the scores (additive noise), but on the decisions themselves (multiplicative noise)

  • J. A. F. Heimel, A. C. C. Coolen, D. Sherrington, Dynamics of the Batch Minority Game with Inhomogeneous Decision noise (2001), preprint


Brings the light of the generating functional technique to the standard MG with random histories. Discusses the difference between the batch and on-line (i.e. standard) MG. Explains a posteriori which are the explicit or implicit approximations of the previous continuous time approaches.

  • A. C. C. Coolen, J. A. F. Heimel, Dynamical Solution of the On-Line Minority Game (2001), preprint


Shows analytically that the broken-ergodicity of MG where agents take into account their impact on the game, is not related to aging, as usual for spin-glasses, but to long term memory.

  • J. A. F. Heimel, A. De Martino, Broken Ergodicity and Memory in the Minority Game (2001), preprint

     

Shows how it is possible to adjust parameters of the game so that one always has cooperation for naive agents (NB: this is done for 'exotic' strategy space, but their conclusions hold for the original MG). This paper has some arguments to predict the value of M. [Note from me : strictly speaking, maximum profit corresponds to Nash equilibria, which are attained by agents taking into account their impact on the game]

  • H. F. Chau, F. K. Chow, How to Attain Maximum Profit in Minority Game ? preprint

Gives bounds on the `complexity' of the MG.

  • Cosma Rohilla Shalizi and David J. Albers, Symbolic Dynamics for Discrete Adaptive Games (2002), preprint


A review of previous papers on the statistical mechanics of the MG

  • A. C. C. Coolen, Non-equilibrium Statistical Mechanics of Minority Games (2002), preprint

The Lempel-Ziv complexity is measured in MG history bit-strings for real and random histories (and intermediary cases): it has a maximum at the transition point for real histories but not random ones, for which it constant.
  •  Milan Rajkovic, Zoran Mihailovic, Quantifying Complexity in the Minority Game,Physica A, vol 325, issues 1-2, (2003) 40-47, preprint

The Gini index (measure of wealth inequality amonts the players) is investigated: it is maximal at the phase transition point
  • K. H. Ho, F. K. Chow, H. F. Chau, Cooperation Comes With Exploitation -- A Study Of The Wealth Inequality In The Minority Game (2004) preprint

A closed-form exact mathematical theory of MG with real market histories using generating functionals.
  • A. A. C Coolen, Generating functional analysis of Minority Games with real market histories (2004), preprint

Shows numerically that the fluctuations of the attendance in the symmetrical phase are depend on the nature of the market history. This only shows up for large enough systems.
  • K. H. Ho, W. C. Man, F. K. Chow, and H. F. Chau, Memory Is Relevant In The Symmetric Phase Of The Minority Game (2004), preprint

Proposes a mathematical theory of the variance of the attendance as a function of the bias in initial strategy valuations for small m for real market histories. Fraction of frozen agents, convergence time and wealth distribution are also treated.
  • K. Y. Michael Wong, S. W. Lim, and Zhuo Gaon, Effects of diversity on multi-agents systems: Minority Games (2005), preprint

Studies populations where each agent can have strategies with various market history length
  • K. E. Mitman, S. C. Choe, N. F. Johnson, Competitive advantage for multiple-memory strategies in an artificial market (2005), preprint

Spherical means that the agents can play linear combinations of their two strategies, with a geometrical constraint. Generating functional give exact expressions for the volatility, but the phenomenology is significantly different from that of the standard MG
  • T. Galla, A.C.C. Coolen, D. Sherrington, Dynamics of a spherical minority game (2003), preprint

The Spherical MG redux: the spherical condition leaves less liberty to the player, and makes the phenomenology of the model much closer to that of the standard MG, while still giving exact expressions for the volatility
  • T. Galla, D. Sherrington, Stationary states of a spherical Minority Game with ergodicity breaking (2005), preprint

Dynamical analytical solution of batch MG with S>1. Instead of frozen agents, one should consider the whole distribution of strategy use frequency. This makes the closure of the set of effective equations more complex.
  • N. Shayeghi, A. C. C. Coolen, Generating functional analysis of batch minority game with arbitrary strategy number (2006), preprint



MG and financial markets

The standard MG can be considered as a very crude model of financial markets, because the minority mechanism is found in markets. Quite a lot of the above papers motivate their study of the MG by that of markets. The following papers try to study specifically the relationships between MG and markets, and not only the MG for its own. Several extension have of course to be considered.



Grand canonical MG with dynamic capital and quasi-periodic producers versus non-adaptive agents. Models with a lot of economic details. Shows that speculators reduce fluctuations, and finds a phase transition when the aggressiveness of the speculators increases.

  • F. Slanina and Y.-C. Zhang, Capital Flow in a Two Component Dynamical System (1999), preprint

Study of the role of producers, speculators, noise traders, and insiders in a market. Shows that speculators and producers live in symbiosis (exact calculus): they need each other. Detailed replica calculus also valid for a standard MG, generalized to any average correlation amongst speculators' strategies.

  • D. Challet, M. Marsili and Y.-C. Zhang, Modelling Market Mechanism with Minority Game (1999), preprint

Volume and price are produced by heterogeneous agents in this grand-canonical MG, where agents do not trade if their best strategies perform worse than a given threshold.

  • N. F. Johnson et al., Trader Dynamics in a Model Market (1999), preprint

Extends the above papers towards more realistic models of markets: agents with dynamical capital and reinvestment and more refined grand-canonical mechanism; also study how to hedge with this kind of modified MG.

  • P. Jefferies, M.L. Hart, P.M. Hui, N.F. Johnson, From market games to real-world markets (2000),preprint

Dynamical capital and reinvestment is considered. This is extension is enough to obtain stylized facts are obtained near the critical point. Also extends the discussion about producers and speculators of cond-mat/9909265

  • D. Challet, A. Chessa, M. Marsili, Y.-C. Zhang, From Minority Games to real markets, Quantitative Finance (2001), preprint

It is argued that grand-canonical MGs contain a fundamental mechanism for short ranged volatility correlations.

  • J.-P. Bouchaud, I. Giardina, M. Mezard, On a universal mechanism for long ranged volatility correlations (2000), preprint

  • I. Giardina, J.-P. Bouchaud, M. Mézard, Microscopic Models for Long Ranged Volatility Correlations (2001), preprint (a few more details)

A very simple MG that leads to stylized facts: an agent plays if she believes that she can beat a given benchmark.

  • D. Challet, M. Marsili and Y.-C. Zhang, Stylized Facts of Financial Markets and Market Crashes in Minority Games (2001), preprint

  • D. Challet, M. Marsili and Y.-C. Zhang, Minority Games and Stylized Facts (2001), preprint

A MG where the heterogeneity is in the fact that agents have no access to complete information (which can be way too complex): each agent has partial information, which is derived from the complete information by her own filter. The filter contains now the quenched disorder. All qualitative results of the standard MG with producers are reproduced (phase transition, market impact, ...). Exact results from the replica calculus. Emphasis on the economic foundation of the minority mechanism. Allows one to study the strong efficiency hypothesis

  • J. Berg, M. Marsili, A. Rustichini, R. Zecchina, Statistical mechanics of asset markets with private information (2001), preprint

Is it possible to identify all parameters of the refined MG of cond-mat/0008387 just by looking at its time series? Yes. Is it possible to predict the direction and amplitude of large movements of such a market model? Yes

  • S. Lamper, S. Howison, N. F. Johnson, Prediction of Large Future Changes in a competitive evolving population (2001), preprint

The results of the preceding preprint are relevant for real financial markets

  • N. F. Johnson, D. Lamper, P. Jefferies, M. L. Hart, S. Howison, Application of Multi-Agent Games to the Prediction of Financial Time Series, preprint

Shows that markets are either minority or majority games depending on the ratio between fundamentalists and trend followers in the market.

  • M. Marsili, Market mechanism and expectations in minority and majority games, Physica A 299, pp. 93-103 (2001), paper

Agents play with different frequencies. Agents playing often are more likely to use different strategies. In addition, it is shown that in inefficient MG markets, the arbitrage opportunity is proportional to the inverse of its frequency. Application to financial markets

  • M. Marsili, M. Piai, Colored Minority Games (2002), preprint

The same model with several types of decision noise, analyzed with generating functionals

  • A. De Martino, Dynamics of Multi-Frequency Minority Games (2003), preprint

Applies different time series analysis methods to a grand canonical MG and compares with the S&P500

  • F. F. Ferreira, G. Francisco, B. S. Machado, P. Muruganandam, Time Series Analysis for Minority Game Simulations of Financial Markets (2002), preprint

Analyses the cause, duration and amplitude of crashes with help of De Bruijn graphs in a Grand Canonical MG

  • P. Jefferies, D. Lamper, N. F. Johnson, Anatomy of extreme events in a complex adaptive system (2002), preprint

Continues the analysis of previous preprint and proposes remedies

  • M. L. Hart, D. Lamper, N. F. Johnson, Crash Avoidance in a Complex System (2002), preprint

A different payoff function is proposed, where the gain at time t depends on the action of agents at time t-1 (see also cond-mat/020622. Note that the discussion parallels that of thispaper, except that agents have no expectation over future price,hence are neither contrarians nor trend-followers in essence.

  • J. V. Andersen, D. Sornette, The $-game (2002), preprint

A much extended grand canonical MG, including market clearing, capital dynamics, inter-temporal payoff, etc, with 3 regimes: bubbles/crashes, intermittency, stable prices.

  • I. Giardina, J.-Ph. Bouchaud, Bubbles, Crashes and Intermittency in Agent Based Market Models (2002), preprint

Surveys the merits of various kinds of grand-canonical MG and MG-like models with intertemporal payoffs

  • Paul Jefferies, Neil F. Johnson, Designing agent-based market models (2002) preprint

Simplifies further the model of cond-mat/0101326:the agents have only one strategy each, and are allowed not to play.In the exact solution, no stylized facts, as P/N is not the correctcontrol parameter for stylized facts. Argues that high volatilityregions are due to a signal-to-noise transition, which explainsfinite size effects in the original MG.

  • D. Challet and M. Marsili, Criticality and finite size effects in a simple realistic model of stock market (2002), preprint

The payoff is modified so that the game is a majority game for small A, and a minority game for large A. Large fluctuations arise near the point where the nature of the game changes from minority to minority game

  • A. De Martino, I. Giardina, M. Marsili, A. Tedeschi, Generalized minority games with adaptive trend-followers and contrarians (2004) preprint

More detailled study of the previous model, showing in particular intermittency

  • A. Tedeschi, A. De Martino, I. Giardina, Coordination, intermittency and trends in generalized Minority Games (2005) preprint

Shows that the structure of bit string histories and binary strategies is the cause of periods of predictability and unpredictability, found in a previous preprint. Applies this to Nasdaq price change amplitude prediction with agent-based models.

  • Jorgen Vitting Andersen, Didier Sornette, A Mechanism for Pockets of Predictability in Complex Adaptive Systems (2004) preprint

Develops theoretical tools for fitting agent-based models to data.

  • N. Gupta, R. Hauser, N. F. Johnson, Forecasting time-series using artificial market models (2005), preprint

Minority Game with another type of strategies:

A MG where players have an alternative kind of strategies: given a history, each agent i has a probability pi to choose the action which was winning last time the history occurred. Evolutionary means that if an agent has a wealth smaller that d, his pi is changed within a range of R (R=1 here).

  • N. F. Johnson et al., Self Organized Segregation within an Evolving Population, PRL 82, 3360 (1999), preprint


Uses the same kind of strategies as above, but modifies the way in which the pi are updated

  • H. Ceva, Self Organization, resources and strategies in a minority game (1999), preprint


The asymmetrical MG with the same kind of strategies as the previous paper

  •  N. F. Johnson et al., Evolutionary freezing in a competitive population (1999), preprint


Detailed studies of the strange phenomena occurring in the above preprint

  • E. Burgos, Horacio Ceva, R.P.J. Perazzo, Quenching and Annealing in the Minority Game (2000), preprint

  • E. Burgos, Horacio Ceva, R.P.J. Perazzo, Dynamical quenching and annealing in self-organization multiagent models (2000), preprint


Confirms that the memory length is not a crucial parameter for this kind of strategies, and propose some analytical formulas based on random walks

  • E. Brugos and H. Ceva, Self organization in a minority game: the role of memory and a probabilistic approach (2000), preprint


Studies in details this kind of strategies with and without memory; finds that the system performs better without memory. Computes the autocorrelation of the memory. Finally, allows the player not to play (grand canonical game).

  • Roland Kay and Neil F. Johnson, Memory and self-induced shocks in an evolutionary population competing for limited resources (2003), , preprint


Proceeding that covers preprints cond-mat/9810142 and cond-mat/9905039.

  • P. M. Hui, T. S. Lo, N. F. Johnson, Segregation in a competing and evolving population(2000), preprint


Proposes a mean-field theory for this kind of strategies.

  • T. S. Lo, P. M. Hui, N. F. Johnson, Theory of Evolutionary Minority Game (2000), preprint


Compares MGs with strategies introduced by D'Hulst and Rodgers (cond-mat/9902001) with MGs studied just above in this section:

  • T. S. Lo, S. W. Lim, P. M. Hui, N. F. Johnson, Evolutionary minority game with heterogeneous strategy distribution (2000), preprint


Analytical approach (master equation) to the model investigated in the above preprints as well as to the MG introduced by Packzuski and Bassler (cond-mat/9905082)

  • Alexei Vazquez, Self-organization in populations of competing agents (2000), preprint

Finds a global cost function that the behaviour of agents with such strategies minimises. Also adds thermal fluctuations and studies their effect.

  • E. Burgos, Horacio Ceva, R.P.J. Perazzo, Thermal Treatment of the Minority Game (2001), preprint

Shows that changing the ratio R between points for winning and for losing leads to clustering (the histogram of the pi is peak around 0) to segregation for R>R_c<1.

  • S. Hod, E. Nakar, Segregation vs. Clustering in the Evolutionary Minority Game, (2002), preprint

In this model, a new p is drawn from a uniform distribution [0,1]. The probability of winning is time dependent, with oscillatory behaviour, which means that there is no real stationary state

  • S. Hod, E. Nakar, Semianalytical approach to the Evolutionary Minority Game, (2002), preprint

A nice theory of agent survival in this model, based on first-passage formalism for random walks with time-dependent (oscillating) probabilities. Shows that Rc=1 in the thermodynamic limit.

  • S. Hod, Time Dependent Random Walks and the Theory of Complex Systems, (2002), preprint


Points out that the role of R has been studied in their papers, that stochastic behaviour of <p> was also observed, and that drawing a new p from a uniform distribution is an important modification of the original rule.

  • E. Burgos, Horacio Ceva, and R.P.J. Perazzo, Comment on Self-Segregation versus Clustering in the Evolutionary Minority Game (2003) preprint

(Long) reply to the previous comment. The oscillatory behaviour is observed for all rules, but its period and strength are not the identical. Differentiates stochastic and oscillatory behaviours.

  • S. Hod, E. Nakar, Strategy updating rules and strategy distributions in dynamical multiagent systems (2003), preprint

Shows that the critical ratio R_c depends on d and N. Introduces a simplified model where p can take only 3 values (called "Three-Group Evolutinary MG") and finds N_c=(d/cst(1-R))2

  • K. Chen, B.-H. Wang, and B. Yuan, Adiabatic theory for the population distribution in the evolutionary minority game, Phys. Rev. E 69, 025102 (2004) preprint

Derives an intermittency correction value to N_c for the Three-Group EMG.

  • K. Chen, B.-H. Wang, and B. Yuan, Theory of the Three-Group Evolutionary Minority Game (2004) preprint

Neural Networks playing a MG can cooperate. The relevant parameters are N and eta, the learning rate. Analytic results (without any details)

  • W. Kinzel, R. Metzler, I. Kanter, Dynamics of Interacting Neural Networks, J. Phys. A 33 (2000), L141-L147, preprint


Gives details of the previous paper. The importance of the strategy parametrisation choice is discussed:

  • W. Kinzel, R. Metzler, I. Kanter, Interacting Neural Networks (2000), preprint


The title says it all. A nice review. Has a section about the two previous works

  • W. Kinzel, Predicting and Generating Time Series by Neural Networks: an Investigation Using Statistical Physics (2000), preprint


Extends the previous preprints, in particular to cryptography.

  • W. Kinzel, Theory of Interacting Neural Networks (2000), preprint


Same principle as the previous preprints, but for more than two alternatives:

  • Liat Ein-Dor, Richard Metzler, Ido Kanter, Wolfgang Kinzel, Multi-Choices Minority Game (2000), preprint


Agents have a neural network based on the principle of punishing the errors (see this preprint from Chialvo and Bak)

  • J. Wakeling, P. Bak, Intelligent Systems in the Context of Surrounding Environment, PRE 64, 051920 (2001), preprint


Agents have two strategies, and play their worst one with a given probability.

  • P. Jefferies, M. Hart, N.F. Johnson, P.M. Hui, Generalized strategies in the Minority Game (2000), preprint

  • M. Hart, P. Jefferies, N. F. Johnson, P. M. Hui, Stochastic strategies in the Minority Game (2000)preprint


Mixed population of agents with "generalized strategies" and standard agents.

  • P. Jefferies, M. Hart, N.F. Johnson, P.M. Hui, Mixed population Minority Game with generalized strategies (2000), preprint


A repeated MG with no memory; only losers at the last time step change their decision with probability p. Typical fluctuations are of order 1. Exactly solved. Note that this make the game a MG without memory: inductive agents without memory taking into account their impact on the game are also able to create fluctuations of order 1, see cond-mat/0004376.

  • G. Reents, R. Metzler, W. Kinzel, A New Stochastic Strategy for the Minority Game (2000), preprint


Strategies are drawn from a set whose size does not depend on the system size.

  • A. Bazzan, R. Bordini, G. Andrioti, R. Vicari and J. Wahle, Wayward Agents in a Commuting Scenario (Personalities in the Minority Game) (2000), Proc. 4th Int. Conf. on MultiAgent Systems (ICMAS-2000), preprint


A quantum MG !

  • S. C. Benjamin, P. M. Hayden, Multi-Player Quantum Games (2000), preprint


Shows numerically that Q learning (a kind of Reinforcement learning procedure) yields a stationary state close to a Nash equilibrium:


  • M. Andrecut and M. K. Ali, Q learning in the Minority Game, PRE 64, 067103 (2001), link


Extended classifier sytems are used and their performance is analyzed:


  • L. M. Hercog and T. C. Fogarty, Social Simulation Using a Multi-Agent Based on Classifier Systems (2001), psfile


Zero-th level classifiers this time:


  • L. M. Hercog and T. C. Fogarty, Co-evolutionary Classifier Systems for Multi-agent Simulation (2002), psfile


Minority Game on networks:

Introduction of personal histories (my personal history = "what I have done for the M last time steps") instead of global histories: cooperation still arises.

  • M. A. R. de Cara et al., Learning, competition and cooperation in simple games (1999), preprint


Another kind of personal histories: it consists of the previous actions of M random neighbours. The connection with the Kauffman networks is then obvious (M=K).

  • M. Paczuski, K. E. Bassler and A. Corral, Self-organized Networks of Competing Boolean Agents (1999), preprint

Same kind of personal history as the previous paper, but the agents placed on a circle. Agents can cooperate:

  • T. Kalinowski, H.-J. Schulz and M. Briese, Cooperation in the Minority Game with Local Information, Physica A 277 (3-4), 502-508 (2000)


Agents play local MGs with local information (there are as many MGs as agents) on square lattices (1-d, 2-d, ...). In this model, there are situations where all agents win at the same time. The effective disorder is annealed.

  • S. Moelbert, P. De Los Rios, The Local Minority Game (2001), preprint


Same as above, but with strategies à la Johnson:

  • E. Burgos, H. Ceva, R. P. J. Perazzo, A Local Minority Game (2002), preprint


A generalized MG with N_c choices, and mixed local and global information

  • H. F. Chau, F. K. Chow, K. H. Ho, Minority Game With Peer Pressure (2003), preprint

A global MG where the agents are linked to neighbours with a random Poisonnian graph, and compare their performance with that of their neighbours, and imitate them when outperformed. Scale-free network of influence and better global coordination emerge

  • M. Anghel, Zoltán Toroczkai, Kevin E. Bassler, G. Korniss, Competition in Social Networks: Emergence of a Scale-free Leadership Structure and Collective E ciency (2004), Phys. Rev. Lett. preprint

A crow/anti-crowd approach to networked population as introduced in the previous paper.

  • Neil F. Johnson,Pak Ming Hui, Crowd-Anticrowd Theory of Collective Dynamics in Competitive, Multi-Agent Populations and Networks (2003), preprint

A more refined approach than the previous paper.

  • T. S. Lo, H. Y. Chan, P. M. Hui, and N. F. Johnson, Theory of Networked Minority Games based on Strategy Pattern Dynamics (2004) preprint

MG where the personal history depends on the actions of neighbours at the previous time step (a la Paczuski). The adaptability as a function of the number of neighbours K is investigated.

  • Aram Galstyan and Kristina Lerman, Adaptive Boolean Networks and Minority Games with Time Dependent Capacities (2004), preprint

Same as previous paper. Several kinds of network, including growing networks are investigated, as well as the role of Darwinian evolution.

  • Baosheng Yuan, Bing-Hong Wang, and Kan Chen, Evolutionary Dynamics in Complex Networks of Competing Boolean Agents (2004), preprint



Various extensions to the Minority Game:

First numerical study of the asymmetric MG:

  • N. F. Johnson et al., Minority Game with Arbitrary Cuttoffs, 1999, preprint


Another kind of asymmetric MG: 1=in the game, 0=out of the game, and agents have incentive to participate, even if the game is risky:

  • Frantisek Slanina, Yi-Cheng Zhang, Dynamical spin-glass-like behavior in an evolutionary game, preprint

Numerical study of the asymmetric MG with time varying resource level with a setup of ref preprint(boolean networks). Best results for K=2.

  • A. Galstyan and K. Lerman, Minority Games and Distributed Coordination in Non-Stationary Environments (2001), preprint

Shows numerically that the fluctuations are reduced by an increase of the asymmetry

  • K. F. Yip, P. M. Hui, T. S. Lo, N. F. Johnson, Efficient resource distribution in a minority game with a biased pool of strategies, Physica A 321, 318-324 (2003)


Several evolutionary schemes for the standard MG:

  • Y. Li et al., Evolution in Minority Games I. Games with a Fixed Strategy Space (1999), preprint

  • Y. Li et al., Evolution in Minority Games II. Games with Variable Strategy Spaces (1999), preprint

Genetic algorithms are used in order to make agents evolve. In 3 words: usually less fluctuations:

  • M. Sysi-Aho, A. Chakraborti and K. Kaski, Intelligent Minority Games with Genetic-Crossover Strategies (2002), preprint

  • M. Sysi-Aho, A. Chakraborti and K. Kaski, Hybridized genetic strategies in game theory (2002), preprint

  • M. Sysi-Aho, A. Chakraborti and K. Kaski, Biology Helps You to Win a Game (2003), preprint



Agents are placed on a circle and imitate their left neighbour with probability p if the latter gains more than themselves

  • F. Slanina, Social organization in the Minority Game model (2000), preprint


NOTE: I have no access to the paper itself, hence, just reproduce the abstract as it:
"After studying the effects of imitation on the mixed population of adaptive agents with different memories competing in a minority game, we have found that when the pure population lies in a crowded regime, the introduction of imitation can considerably improve cooperation among agents in a money market."

  • H.J. Quan , B.H. Wang , P.M. Hui , X.S. Luo , Cooperation in the mixed population minority game with imitation , Chinese Physics Letters, 18 (9): 1156-1158 SEP 2001

Two different models of minority games with three alternatives are considered:

  • R. D'hulst, G. J. Rodgers, Three sided complex adaptive systems (1999), preprint


A MG where agent have to chose between K rooms; the ones in the less chosen room win. Reproduces statistical features of the standard MG (attendance fluctuations, phase transition, ...)

  • F. K. Chow, H. F. Chau, Multiple choices Minority Game (2001), preprint


A MG where agents' changing decisions are replaced by a global cut-and-paste process. [Note from me: in the original MG, the fluctuations are minimal at the point where H goes to zero, in the thermodynamic limit]

  • R. D'hulst, G. J. Rodgers, Percolation and Depinning Transition in Cut-and-Paste Models of Adaptation (2001), preprint


The MG is modified in order to model the emergence of colonies of birds in presence of predation.

  • J. L. Tella, M. A. R. de Cara, O. Pla, F. Guinea,  A Model for Predation Pressure in Colonial Birds (2001), preprint


A game where the agents have K choices, and are rewarded if their choice at time t is chosen by more people at time t+1. This is in essence the same idea as in this preprint

  • W.A.T. Wan Abdullah, Learning strategies for global games with delayed payoffs (2002) preprint

Several minority games are coupled: each individual game plays the sign of its outcome. The strength of interaction is shown to have a measurable effect at all levels.


  • F. Földy, Z. Somogyvári, P. Erdi, Hierarchically Organized Minority Games (2003), preprint


A game where the two alternatives are two suppliers that have each a given quantity of resource. Being in the minority is not enough. As this amounts to consider a different kind of payoff in the MG, fluctuations are similar in essence to those of the MG. Phase transitions when the resource level is varied. Has strong analogies with market entry games


  • R. Savit, S. A. Brueckner, H. Van Dyke Parunak, J. Sauter, Phase Structure of Resource Allocation Games (2003), preprint

The MAJORITY game is solved exactly for naive and sophisticated agents. Very similar to a Hopfield model. A transition between spin-glass and retrieval phases found. Although all the agents freeze in both cases, the stationary state reached by the naive agents is not a Nash equilibrium.

  • P. Kozlowski and M. Marsili, Statistical Mechanics of the Majority Game 2003, preprint

A continuous time MG situation where users send requests to one of two computers, namely to the one that was the least busy some time ago. If the information about the state of the computers is wrong with some probability, the efficiency of the system improves upto a point.

  • Richard Metzler, Mark Klein, Yaneer Bar-Yam,  Efficiency through disinformation, preprint

Experiments

MG played between human beings. Finds that the lengthy of the bit string history given to the agents is irrelevant to cooperation, and that humans do cooperate. Interesting discussion about the game theoretical aspect of the game.

  • G. Bottazi and G. Devetag, Coordination and Self-Ogranization in Minority Games: Experimental Evidence (2002) preprint

MG played between human beings. Main result: the length of the bit string history is not as much relevant as its nature: the players cannot cooperate if fed with random histories

  • T. Platkowski and M. Ramsza, Playing minority game, Physica A 323, 726 (2003),

MG played between human beings. Finds interesting oscillating fluctuations as a function of time. The simplest the behaviour, the better the player. Argues that human beings have a memory of 3 time steps.

  • R. Savit, K. Koelle, W. Treynor and R. Gonzalez, Man and Superman: Human limitations, Innovation and Emergence in Resource Competition, in Proceedings of Collectives and the design of complex systems (2003)

MG played by one human being against artificial players. Data suggests that human beings have a memory of 3 time steps. Human players perform poorly in the asymmetric phase, and well in the symmetric phase.

  • P. Laureti, P. Ruch, J. Wakeling, Y.-Ch. Zhang, The Interactive Minority Game: a Web-based investigation of human market interactions, Physica A 331 (2004) 651-659, preprint
  • P. Ruch, J. Wakeling, Y.-Ch. Zhang, The Interactive Minority Game: Instructions for Experts, preprint
  • Human players are given either information that makes them naive or sophisticated. Resulting fluctuations are accordingly high or low.

    • T. Chmura, T. Pitz, Minority Game - an experimental investigation and simulations (2005)preprint


Relevant papers:

Properties of anti-persistent time series are studied on a De Bruijn Graph. Relevant for MGs with populations of various memory length (cond-mat/9903164 and cond-mat/9909265). Explains why players with a larger memory have an edge only if anti-persistence is large enough (i.e. alpha small enough).

  • R. Metzler, Antipersistent Binary Time Series (2001), preprint

Ph.D Theses related to the MG


  1. D. Challet, Modelling Market Dynamics: Minority Games and beyond, Fribourg (CH), July 2000, psfile

  2. A. de Martino, Replica Symmetry Breaking and Long Term Memory in Large Games with Heterogeneous Players, SISSA-Trieste (IT) (2001), psfile

  3. J. A. F Heimel, Dynamics of Learning by Neurons and Agents: Generating Functionals for Disordered Systems (2002), pdffile

  4. R. Metzler, Neural Networks, Game Theory and Time Series Generation (2002), psfile

  5. M. A. R. de Cara, Métodos estadísticos en Ecología Colonialidad y aprendizaje en aves (2003), pdffile

Reviews

On analytical results on the MG, and on the relationship between the MG and markets

  • M. Marsili, Toy models of markets with heterogeneous interacting agents (2002), psfile

On MG-inspired market models, crash prediction, and remedies

  • D. lamper et al., Managing catastrophic changes in a collective, (2002), preprint

On the relationship between payoffs, learning, and efficiency. And on what payoff to give to the agents so that they minimize a given quantity

  • D. Challet, Competition between adaptive agents: from learning to collective efficiency and back (2002), preprint

Review of the application of statistical mechanics to various heterogeneous agent-based models, including MG

  • A. De Martino, M. Marsili, Statistical mechanics of socio-economic systems with heterogeneous agents (2006), preprint

Review of current use of the MG as a model of financial markets

  • T. Galla, G. Mosetti, Y.-C. Zhang, Anomalous fluctuations in Minority Games and related multi-agent models of financial markets (2006), preprint



Econophysics Forum