The discussion outlines the ways in which crisis emasculates traditional methodology as used in economics by making the core assumptions of this type of analysis (temporarily) untenable. Our critique of traditional methodology is limited to its inability to address this critical subset of social...

This paper presents an adaptive learning model for market-making under the reinforcement learn-ing framework. Reinforcement learning is a learning technique in which agents aim to maximize the long-term accumulated rewards. No knowledge of the market environment, such as the order arrival or...

The Minority Game is a simple yet highly non-trivial agent-based model for a complex adaptive system. Here, we provide an explanation of the game's fluctuations which is both intuitive and quantitative, and which applies over the entire parameter range of interest. The physical idea behind our...

We present detailed numerical results for a modified form of the so-called Minority Game, which provides a simplified model of a competitive market. Each agent has a limited set of strategies, and competes to be in a minority. An evolutionary rule for strategy modification is included to mimic...

We study a model of a competing population of N adaptive agents, with similar capabilities, repeatedly deciding whether to attend a bar with an arbitrary cutoff L. Decisions are based upon past outcomes. The agents are only told whether the actual attendance is above or below L. For L∼N/2, the...

We use game theory and the Santa Fe Artificial Stock Market, an agent-based model of an evolving stock market, to study the properties of strategic Nash equilibria in financial markets. We discover two things: there is a unique strategic equilibrium in the market, and this equilibrium in...

This paper discusses the concept of path dependence in macrodynamics, and identifies practical difficulties associated with building path-dependent macrodynamic models of the sort that Keynesians and Schumpeterians regard as necessary for the successful study of long-term growth and development....

We analyze the evolution and extent of income tax evasion under alternative governmental policies in an agent-based model with heterogeneous agents. A novel aspect of our modeling is the use of an exponential utility function, which allows us to assume rather realistic audit probabilities and to...