Risk Management

Open Risk White Paper 1: Revisiting Simple Concentration Indexes

We review the definitions of widely used concentration metrics such as the concentration ratio, the HHI index and the Gini and clarify their meaning and relationships. This new analytic framework helps clarify the apparent arbitrariness of simple concentration indexes and brings to the fore the underlying unifying concept behind these metrics, thereby enabling their more informed use in portfolio and risk management applications. We also propose that the sensitivity of concentration indexes to growing concentration should be a defining criterion for adopting an index and explore the sensitivity of common indexes to changing portfolio concentrations. We show that this sensitivity can vary significantly between indexes for parametric families of portfolio distributions and hence selecting and using a simple concentration index should take this aspect carefully into consideration

Securitisation versus Banking

The ever elusive CMU dream

There is(/was) renewed interest in EU-land over deepening a capital markets union, aka CMU. It is among the initiatives being pursued by the Commission in order to help accelerate growth in the European Union.

The initiative encompasses many elements, both around equity (shares) and debt markets. One important pillar of the CMU aims to re-launch some version of an EU securitisation market. This segment was never really defined in a EU-wide basis. In the pre-crisis European financial landscape there were wide disparities in the degree of adoption, legal frameworks, preferred structures etc. among the different countries comprising the EU. In any case, since the financial crisis there has been a steady decline in securitisation volumes, which amongst others, hinders certain types of exceptional central bank measures (i.e., purchasing securitised assets).

A mini course on risk management, its perils and the silver lining

When talking about risk management, it is not very clear what we are talking about in broad terms, it is definitely not getting clearer when we start getting into the details and it is finally not clear how to best use the (possibly flawed) insights we produce.

We are happy to publish the first installment of a trilogy that focuses on the risk factors that can turn any credit portfolio toxic.

The first topic is default correlation, a topic that is both core to understanding credit risk and much misunderstood.

Enjoy!