We analyze two robust portfolio selection models, where a mean-variance investor considers possible deviations from a reference distribution of asset returns, adopting a maxmin criterion. The two models differ in the metric used to measure the distance between the reference distribution of asset...

When the riskiness of an asset increases, then, arguably, some risk-averse agents that were previously willing to hold on to the asset are no longer willing to do so. Aumann and Serrano (2008) have recently proposed an index of riskiness that helps to make this intuition rigorous. We use their...

We propose a portfolio selection model based on a class of preferences that coincide with mean-variance preferences on their domain of monotonicity, but differ where mean-variance preferences fail to be monotone.

We propose a new approach to the study of stock returns. We develop a simple model to show that, in the long run, the average rate of return on the market portfolio equals the average growth rate of income plus an average payout rate measuring the quantity of financial resources distributed or...

We propose a model of portfolio selection under ambiguity, based on a two-stage valuation procedure which disentangles ambiguity and ambiguity aversion. The model does not imply 'extreme pessimism' from the part of the investor, as multiple priors models do. Furthermore, its analytical...

We solve two robust portfolio selection problems, where a maxmin criterion is adopted to deal with parameter uncertainty. The two models, which yield closed formulae for the optimal allocation, lend themselves to be thoroughly analyzed both from a geometric and a game-theoretic point of view.

A new approach to the study of stock returns is proposed. A simple model is developed to show that, in the long run, the average rate of return on the market portfolio equals the average growth rate of income plus an average payout rate measuring the quantity of financial resources distributed...

We propose a portfolio selection model based on a class of preferences that coincide with mean-variance preferences on their domain of monotonicity, but differ where mean-variance preferences fail to be monotone.

Around the turn of the Twentieth century, US and euro area long-term bond yields experienced a remarkable decline and remained at historically low levels even in the face of rising short-term rates (the so called "conundrum"). This unusual phenomenon has been analyzed by many researchers through...