It is now an accepted fact that the majority of financial markets worldwide are neither normal nor constant, and South Africa is no exception. One idea that can be used to understand such markets and has been gaining popularity recently is that of regimes and regime-switching models. In this...

We formulate a distributionally robust optimization problem where the deviation of the alternative distribution is controlled by a φ-divergence penalty in the objective, and show that a large class of these problems are essentially equivalent to a mean-variance problem. We also show that while...

Portfolio optimization has been a central problem in finance, often approached with two steps: calibrating the parameters and then solving an optimization problem. Yet, the two-step procedure sometimes encounter the ``error maximization'' problem where inaccuracy in parameter estimation...

We establish the existence and uniqueness of the equilibrium for a stochastic mean-field game of optimal investment. The analysis covers both finite and infinite time horizons, and the mean-field interaction of the representative company with a mass of identical and indistinguishable firms is...

The performance of dynamic trading and investment strategies can be difficult to predict. Although not without its problems, analysis of the historical performance of a strategy can provide valuable insight into its general risk and return properties. Furthermore, historical analysis allows one...

In this paper, we derive upper and lower bounds on the Range Value-at-Risk of the portfolio loss when we only know its mean and variance, and its feature of unimodality. In a first step, we use some classic results on stochastic ordering to reduce this optimization problem to a parametric one,...

This paper studies an optimal investment and consumption problem with heterogeneous consumption of basic and luxury goods, together with the choice of time for retirement. The utility for luxury goods is not necessarily a concave function. The optimal heterogeneous consumption strategies for a...

In this paper, we study the worst-case distortion risk measure when information about distortion functions is partially available. We obtain the explicit forms of the worst-case distortion functions from several different sets of plausible distortion functions. When there is no concavity...

In this study, a new uncertain portfolio optimization model is proposed that is capable to be employed in the presence of fuzzy data and linguistic variables. It should be noted that mean (return), absolute deviation (non-systematic risk measure), and beta (systematic risk measure) as well as...

The goal of this research is to present an uncertain multi-period portfolio management (UMPPM) model in the context of fuzzy uncertainty. Accordingly, three objectives including terminal wealth, risk, and liquidity as well as realistic constraints such as budget constraint and cardinality...