Covariance matrix forecasts of financial asset returns are an important component of current practice in financial risk management. A wide variety of models, ranging from matrices of simple summary measures to covariance matrices implied from option prices, are available for generating such...

The purpose of this paper is to disclose how the Gaussian form of the concept of market efficiency is at the origin of the contemporary professional debate on passive index-linked management which continues on despite the growing popularity of indexing among investment management practitionners...