Archegos Risk: Podcast with Fabrizio Anfuso on Computing Exposures
- The 2021 Archegos default put risk management of highly leveraged counterparty exposures at the top of banks’ priority lists.
- Fabrizio Anfuso, a senior technical specialist at the Bank of England, and Dimitrios Karyampas, a visiting lecturer at Bocconi University and the University of Zürich, have been active...
- Anfuso's solution combines his experience in modeling wrong-way risk (WWR) with tools proposed by other researchers.
Following the 2021 Archegos default, leading to a dire need for better risk management, Fabrizio Anfuso developed a new framework. This framework focuses on stress-testing exposure to tail events, especially leveraged counterparty risk management. Anfuso, a Bank of England expert, combines wrong-way risk modeling with Gaussian distributions to generate stress scenarios. This approach, inspired by models from experts like Michael Pykhtin, aims to improve clarity in leveraged counterparty risk management. News Directory 3 highlights the importance of such advancements, particularly for a wider understanding of potential future exposure. Anfuso plans to improve clarity further with this framework. Discover what he plans to reveal next.
Bank of England Expert Unveils New Framework for Leveraged Counterparty Risk Management
The 2021 Archegos default put risk management of highly leveraged counterparty exposures at the top of banks’ priority lists. The $10 billion hit that followed the family office’s collapse made a strong case for quants seeking solutions to this complex problem.
Fabrizio Anfuso, a senior technical specialist at the Bank of England, and Dimitrios Karyampas, a visiting lecturer at Bocconi University and the University of Zürich, have been active researchers in this area. They developed a framework for stress-testing exposure to tail events, focusing on leveraged counterparty risk management.
Anfuso’s solution combines his experience in modeling wrong-way risk (WWR) with tools proposed by other researchers. It uses a Gaussian copula to model the WWR correlation between counterparty creditworthiness and portfolio performance, along with a mixture of Gaussian distributions to capture the probability distribution of credit exposures.
Anfuso said his approach was inspired by models from Michael Pykhtin, a senior Federal Reserve economist, and Matthias Arnsdorf of JP Morgan.
“My contribution is merging these two approaches using a new tool,” Anfuso said.”Michael proposed the usage of a copula to filter the scenarios that drive the exposure conditional upon default. Matthias [provided] the correct intuition that it’s not just a matter of selecting a severe scenario. it’s also a matter of having scenarios that are generated by a heavy-tailed distribution.”
Anfuso incorporates mixture models to replicate heavy tails, citing their adaptability and adaptability to complex credit exposure distributions.
According to Anfuso, modeling leveraged counterparty risk isn’t purely scientific. Some steps rely on the practitioner’s experience and risk perception,such as calibrating the copula coefficient. There isn’t a single correct value for it, similar to Pykhtin’s model. The number of Gaussian distributions in the mixture also requires judgment to balance explanatory power and avoid overfitting.
The framework aims to generate stress scenarios, making it a key tool for monitoring this type of exposure. “This is a stress-testing model,” Anfuso said. “Stress testing is pretty much the main tool to monitor this type of exposure.”
Anfuso described his earlier approaches as bottom-up, relying on granular credit portfolio facts. In contrast, most other approaches are top-down, depicting a broader picture of credit exposure without modeling individual counterparty circumstances.
A top-down approach is less sensitive to data limitations from clients. Anfuso is exploring solutions to improve clarity, including the potential role of third parties.
This latest framework leans towards a top-down approach, aligning with Anfuso’s goal to extend his work to a wider credit portfolio model for bank management.
What’s next
anfuso intends to further develop the framework for broader submission in credit portfolio management, aiming to provide banks with a more complete tool for managing leveraged counterparty risk.