Skip to main content

The limitations of using correlation in default prediction

Correlation as a concept has value when it comes to hedging risk, but users must also recognise its limitations in predicting the likelihood of outlier events.

aaron-brown
Aaron Brown

Suppose you have a portfolio of 11 bonds, each with a 10% probability of default, and the defaults are uncorrelated. What is the probability of zero defaults; one default; or all 11 defaulting?

If you are careless, you’ll answer 0.911 = 31% for zero, 11 x 0.910 x 0.1 = 38% for one, and 0.111 = 0.000000001% for 10. These computations are correct if the defaults are independent events. But that is

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 copy this content. Please contact info@risk.net to find out more.

Sorry, our subscription options are not loading right now

Please try again later. Get in touch with our customer services team if this issue persists.

New to Risk.net? View our subscription options

Want to know what’s included in our free membership? Click here

Show password
Hide password

The wild world of credit models

The Covid-19 pandemic has induced a kind of schizophrenia in loan-loss models. When the pandemic hit, banks overprovisioned for credit losses on the assumption that the economy would head south. But when government stimulus packages put wads of cash in…

Most read articles loading...

You need to sign in to use this feature. If you don’t have a Risk.net account, please register for a trial.

Sign in
You are currently on corporate access.

To use this feature you will need an individual account. If you have one already please sign in.

Sign in.

Alternatively you can request an individual account here