We introduce a simple equilibrium model of a market for loans. Households lend to firms and form expectations about their loan default probability. Under heterogeneous expectations, with switching between forecasting strategies driven by reinforcement learning, even a small fraction of...

This paper discusses dynamic evolutionary multi-agent systems, as introduced by Brock and Hommes (1997). In particular the heterogeneous agent dynamic asset pricing model of Brock and Hommes (1998) is extended by introducing derivative securities by means of price contingent contracts. Numerical...

This paper develops the notion of a Large Type Limit (LTL) describing the average behavior of adaptive evolutionary systems with many trader types. It is shown that generic and persistent features of adaptive evolutionary systems with many trader types are well described by the large type limit....

Brock and Hommes (1997) introduce the concept of adaptive rational equilibrium dynamics (ARED)}, where agents choose between a costly rational expectation forecast and a cheap naive forecast, and the fractions using each of the two strategies evolve over time and are endogenously coupled to the...

This paper formalizes the idea that more hedging instruments may destabilize markets when traders are heterogeneous and adapt their behavior according to experience based reinforcement learning. We investigate three different economic settings, a simple mean-variance asset pricing model, a...

This paper formalizes the idea that more hedging instruments may destabilize markets when traders have heterogeneous expectations and adapt their behavior according to experience based reinforcement learning. In a simple asset pricing model with heterogeneous beliefs the introduction of...

This paper develops the notion of a Large Type Limit (LTL) describing the dynamical behavior of heterogeneous markets with many trader types. It is shown that generic and persistent features of adaptive evolutionary systems with many trader types are well described by the large type limit....

We propose behavioral learning equilibria as a plausible explanation of coordination of individual expectations and aggregate phenomena such as excess volatility in stock prices and high persistence in inflation. Boundedly rational agents use a simple univariate linear forecasting rule and...

We construct an evolutionary version of Theocharis (1960)'s seminal work on the stability of equilibrium in multi-player quantity-setting oligopolies. Two sets of behavioral heuristics are investigated under fixed and endogenously evolving fractions: (myopic) Cournot firms vs. Nash firms and...

We discuss recent work on bounded rationality and learning in relation to Soros' principles of reflexivity and stress the empirical relevance of non-rational, almost self-fulfilling equilibria in positive feedback systems. We fit a behavioral asset pricing model with heterogeneous expectations...