This paper presents evidence that Ordinary Least Squares estimators of beta coefficients of major firms and portfolios are highly sensitive to observations of extremes in market index returns. This sensitivity is rooted in the inconsistency of the quadratic loss function in financial theory. By...

This paper examines a mean-Gini model of systematic risk estimation that resolves some econometric problems with mean-variance beta estimation and allows for heterogeneous risk aversion across investors. Using the mean-extended Gini (MEG) model, we estimate systematic risks for different degrees...

We consider decision-making under risk in which random events affect the value of the portfolio multiplicatively, rather than additively. In this case, a higher variability in the rate of return not only is associated with a higher risk, a bad property, but also engenders a higher expected...