Risk 2002 USA: World Bank’s Perlin questions validity of risk model assumptions
The World Bank’s chief financial officer, Gary Perlin, questioned whether some of the broad assumptions used in risk modelling were still valid in the current economic climate today during a keynote address at Risk magazine’s Risk 2002 USA conference in Boston.
Events such as Enron’s collapse, US corporate credit events and Argentina’s sovereign default, have called into question some aspects of current thinking on risk management, according to Perlin. “We are now questioning whether some of the broad assumptions underlying our models are still valid.”
Other open questions included whether or not changes in risk tolerance among investors, and generally higher volatility in financial markets, are part of a structural change, or are simply changing with the economic cycle, he said.
Meanwhile, Harry Markowitz – pioneer of modern portfolio theory – took a different tack, using his keynote address to present his latest research on portfolio management. Using utility theory, Markowitz demonstrated how a heuristic utility function can produce comparable risk-reward characteristics to that of an optimal solution calculated via simulation for a simple small portfolio.
Speaking of the case of a large portfolio including a dozen asset classes and a thousand individual securities, Markowitz said: “If all the world’s current computing power were to have started trying to find the optimal solution - including all state variables and time periods - for a very large portfolio back at the time of the big bang, it would still be calculating now.” Whether or not the similarity between the heuristic and optimal solutions found for a simple portfolio holds for large portfolios is not yet known.
Only users who have a paid subscription or are part of a corporate subscription are able to print or copy content.
To access these options, along with all other subscription benefits, please contact info@risk.net or view our subscription options here: http://subscriptions.risk.net/subscribe
You are currently unable to print this content. Please contact info@risk.net to find out more.
You are currently unable to copy this content. Please contact info@risk.net to find out more.
Copyright Infopro Digital Limited. All rights reserved.
You may share this content using our article tools. Printing this content is for the sole use of the Authorised User (named subscriber), as outlined in our terms and conditions - https://www.infopro-insight.com/terms-conditions/insight-subscriptions/
If you would like to purchase additional rights please email info@risk.net
Copyright Infopro Digital Limited. All rights reserved.
You may share this content using our article tools. Copying this content is for the sole use of the Authorised User (named subscriber), as outlined in our terms and conditions - https://www.infopro-insight.com/terms-conditions/insight-subscriptions/
If you would like to purchase additional rights please email info@risk.net
More on Risk management
Consortium backs BGC’s effort to challenge CME
Banks and market-makers – including BofA, Citi, Goldman, Jump and Tower – will have a 26% stake in FMX
Revealed: the three EU banks applying for IMA approval
BNP Paribas, Deutsche Bank and Intesa Sanpaolo ask ECB to use internal models for FRTB
FICC takes flak over Treasury clearing proposal
Latest plans would still allow members to bundle clearing and execution – and would fail to boost clearing capacity, critics say
Buy side would welcome more guidance on managing margin calls
FSB report calls for regulators to review existing standards for non-bank liquidity management
Japanese megabanks shun internal models as FRTB bites
Isda AGM: All in-scope banks opt for standardised approach to market risk; Nomura eyes IMA in 2025
Benchmark switch leaves hedging headache for Philippine banks
If interest rates are cut before new benchmark docs are ready, banks face possible NII squeeze
Op risk data: Tech glitch gives customers unlimited funds
Also: Payback for slow Paycheck Protection payouts; SEC hits out at AI washing. Data by ORX News
The American way: a stress-test substitute for Basel’s IRRBB?
Bankers divided over new CCAR scenario designed to bridge supervisory gap exposed by SVB failure