Post-Crash Economics Society: Risk models & credit ratings are not wrong, the credence bank regulators give these is

Sir, since I was travelling I missed David Pilling’s “Crash and learn: should we change the way we teach economics?” October 1.

It discusses the Post-Crash Economics Society that was created by students at Manchester university, mostly in response to “glaring failure of mainstream economics [that failed] to explain, much less foresee, the financial crash of 2008.”

In it Pilling quotes Andrew Haldane, chief economist at the Bank of England: “We all became overly enamoured of a particular framework for thinking, or a modelling approach… It became something of a methodological monoculture [that] was not well equipped for dealing with economies or financial systems close to, or at, breaking point.”

That sounds about right. It was not the models’ faults, but the fault of those using the models.

For instance bank regulators, with mindboggling hubris, and blind faith in the models, using only knowledge, decided that the capital requirements for banks should be based on risk models using ex ante perceived risks. That was dumb. Clearly any regulatory wisdom would have indicated that those capital requirements, should be based on the so much more dangerous consequences to the bank system that could be caused if those risk models or risk perceptions, like credit ratings, turned out to be wrong.

The faster that is understood, the faster we can bridge the differences between those who, like Angus Deaton, though accepting that “economics is a broad church” yet argue that it “needs to be kept rigorous”, and those who, like Joe Earl, want it to be “more an exploration of ideas, and less a training in the economic priesthood.”

Of course, that will require bank regulators to declare much mea-culpa, or in other ways upsetting a lot the cozy relations in their mutual admiration club.

Here a more extensive aide memoire on some of the monstrosities of such regulations.

@PerKurowski ©