Many interactive environments can be represented as games, but they are so large and complex that individual players are in the dark about others' actions and the payoff structure.  This paper analyzes learning behavior in such 'black box' environments, where players' only source of information...

There is widespread disagreement about the role of housing wealth in explaining consumption.  This paper exploits liquid and illiquid wealth time series from household balance sheet data for South Africa, previously constructed by the authors, to explain fluctuations in the ratios of...

Consider a finite, normal form game G in which each player position is occupied by a population of N individuals, and the payoff to any given individual is the expected payoff from playing against a group drawn at random from the other positions.  Assume that individuals adjust their behavior...

Alpha is the amount by which the returns from a given asset exceed the returns from the wider market.  The standard way of estimating alpha is to correct for correlation with the market by regressing the asset's returns against the market returns over an extended period of time and then apply...

Stochastic learning models provide sharp predictions about equilibrium selection when the noise level of the learning process is taken to zero.  The difficulty is that, when the noise is extremely small, it can take an extremely long time for a large population to reach the stochastically...

Traditional methods for analyzing portfolio returns often rely on multifactor risk assessment, and tests of significance are typically based on variants of the t-test.  This approach has serious limitations when analyzing the returns from dynamically traded portfolios that include derivative...

We build a 4-equation model of the inflation process in South Africa (which has recently adopted inflation targeting), including the exchange rate, consumer prices, producer price, and import prices. This provides useful information on the speed and extent of exchange rate pass-through, and...

Interconnections among financial institutions create potential channels for contagion and amplification of shocks to the financial system.  We propose precise definitions of these concepts and analyze their magnitude.  Contagion occurs when a shock to the assets of a single firm causes other...

The diffusion of an innovation can be represented by a process in which agents choose perturbed best responses to what their neighbors are currently doing.  Diffusion is said to be fast if the expected waiting time until the innovation spreads widely is bounded above independently of the size...

This paper proposes that all new euro area sovereign borrowing be in the form of jointly guaranteed Eurobonds.  To avoid classic moral hazard problems and to insure the guarantors against default, each country would pay a risk premium conditional on economic fundamentals to a joint debt...