Operational VaR: a Closed-Form Approximation

Klaus Böcker and Claudia Klüppelberg investigate a simple loss distribution model for operational risk. They show that, when loss data are heavy-tailed (which in practice they are), a simple closed-form approximation for the OpVaR can be obtained. They apply this approximation in particular to the Pareto severity model, for which they obtain also a simple time scaling rule for the operational VaR.