Transitions in the Stock Markets of the US, UK, and Germany

In an analysis of the US, the UK, and the German stock market we find a change in the behavior based on the stock's beta values. Before 2006 risky trades were concentrated on stocks in the IT and technology sector. Afterwards risky trading takes place for stocks from the financial sector. We show that an agent-based model can reproduce these changes. We further show that the initial impulse for the transition might stem from the increase of high frequency trading at that time

Cooperation in a resource extraction game

An exhaustible stock of resources may be exploited by N players. An arbitrarily long duration of the game is only possible, if the utility function satisfies certain restrictions at small values R of extraction. We find that stability against unilateral defection occurs if the elasticity of the marginal utility turns out to be larger than (N - 1 )/N, however independent of the value of the discount factor. Hence we find that cooperation does not depend on the discount factor for a certain range of elasticities. Analogy to phase transitions in statistical physics is discussed.

Time-variation of higher moments in a financial market with heterogeneous agents: An analytical approach

A growing body of recent literature allows for heterogenous trading strategies and limited rationality of agents in behavioral models of financial markets. More and more, this literature has been concerned with the explanation of some of the stylized facts of financial markets. It now seems that some previously mysterious time-series characteristics like fat tails of returns and temporal dependence of volatility can be observed in many of these models as macroscopic patterns resulting from the interaction among different groups of speculative traders. However, most of the available evidence stems from simulation studies of relatively complicated models which do not allow for analytical solutions. In this paper, this line of research is supplemented by analytical solutions of a simple variant of the seminal herding model introduced by Kirman [1993]. Embedding the herding framework into a simple equilibrium asset pricing model, we are able to derive closed-form solutions for the time-variation of higher moments as well as related quantities of interest enabling us to spell out under what circumstances the model gives rise to realistic behavior of the resulting time series --

International Lessons for the Property Price Boom in South Africa

South Africa appears to share some of the characteristics (property price boom, easing of monetary policy, strong domestic demand growth) of asset price booms in industrial countries that were often followed by a period of weak growth. The international experience suggests that a number of practical obstacles need to be overcome before a more proactive role of monetary policy is warranted. However, a larger variety of available mortgage contracts, including longer-term fixed-rate contracts, should allow for a more efficient allocation of interest rate risks. Also, a more systematic nationwide collection of property price data, including data on commercial property price developments, would provide a more representative basis for analysis.Asset Prices,property prices,monetary policy,economic development

Satisfaction with Democracy and Collective Action Problems: The Case of the Environment

Using modern methods for analyzing multi-level data, we find that, by and large, citizens of OECD countries are more satisfied with the way democracy works in their country if more environmental policies are in place and if environmental quality is higher. We also document that parents care about carbon dioxide emissions more than non-parents and that those with a high willingness to pay for environmental quality deplore intervention through government policies.Collective action problems, environmental economics and policy, satisfaction with democracy

Excess Volatility and Herding in an Artificial Financial Market: Analytical Approach and Estimation

Several agent-based models have been proposed in the economic literature to explain the key stylized facts of financial data: heteroscedasticity, fat tails of returns and long-range dependence of volatility. Agentbased models view these empirical regularities as emerging properties of interacting groups of boundedly rational agents in financial markets. The complexity of these interacting agent models has largely constrained their analytical treatment, limiting their analysis mainly to Monte Carlo simulations. In order to overcome this limitation, we introduce a ‘minimalist’ model of an artificial financial market, along the lines of our previous contributions, based on herding behavior among two types of traders. The simplicity of the model allows for an almost complete analytical characterization of both conditional and unconditional statistical properties of prices and returns. Moreover, the underlying parameters of the model can be estimated directly, which permits an assessment of its goodness-of-fit for empirical data. While the performance of the model for domestic stock markets has been the focus of a previous contribution, in this paper we report results for selected exchange rates against the US dollar.Herd Behavior; Speculative Dynamics; Fat Tails; Volatility Clustering.