This paper is concerned with the subject of how the three main approaches to model aggregate fluctuations are related. That is, we are interested in the relation between real business cycle models, endogenous business cycle models and sunspot equilibria models. It is shown that there exists an...

We analyse an extended version of the dynamical mean-field Ising model. Instead of classical physical representation of spins and external magnetic field, the model describes traders' opinion dynamics. The external field is endogenised to represent a smoothed moving average of the past state...

This research involved developing an optimal stock investment decision strategy which offers minimum risk to the potential investor for counters listed on the Zimbabwe Stock Exchange. Three counters were compared namely Econet Wireless, Delta and Old Mutual. The first phase of the project...

Societies provide institutions that are costly to use, but able to enforce long-run relationships. We study the optimal decision problem of using self-governance for risk sharing or governance through enforcement provided by these institutions. Third-party enforcement is modelled as a costly...

When people share risk in financial markets, intermediaries provide costly enforcement for most trades and, hence, are an integral part of financial marketsu0092 organization. We assess the degree of risk sharing that can be achieved through financial markets when enforcement is based on the...

Exchanges and other trading platforms are often vertically integrated to carry out trading, clearing and settlement as one operation. We show that such vertical silos can prevent efficiency gains from horizontal consolidation of trading and settlement platforms to be realized. Independent of the...

Reputation effects and other-regarding preferences have both been used to predict cooperative outcomes in markets with inefficient equilibria. Existing reputation-building models require either infinite time horizons or publicly observed identities, but cooperative outcomes have been observed in...

In this article, a modelling framework for the information transmission between agents in an evolutionary game setting is proposed. Agents observe traits which reflect past and present behaviour and success of other agents. If agents imitate more successful agents based on these traits, the...

In this paper we analyze the frequently observed phenomenon that (i) some members of a team ("black sheep") exhibit behavior disliked by other (honest) team members, who (ii) nevertheless refrain from reporting such misbehavior to the authorities (they set up a "wall of silence"). Much cited...