This paper argues that the conventional definition of the elasticity of complementarity is not well suited to deal with the case of increasing returns. It proposes a slightly different formula, that uses a distance function formulation instead of a production function. The proposed definition...

Portfolio risk is in an important way driven by 'abnormal' returns emanating from heavy tailed distributed asset returns. The theory of regular variation and extreme values provides a model for this feature of financial data. We first review this theory and subsequently study the problem of...