Tuesday, February 25, 2014

Slow Clap

From: http://www.zerohedge.com/news/2014-02-23/tyranny-models-or-dont-fear-reaper
The tyranny of models is rampant in almost every aspect of our investment lives, from every central bank in the world to every giant asset manager in the world to the largest hedge funds in the world. There are very good reasons why we live in a model-driven world, and there are very good reasons why model-driven institutions tend to dominate their non-modeling competitors. The use of models is wonderfully comforting to the human animal because it’s what we do in our own minds and our own groups and tribes all the time. We can’t help ourselves from applying simplifying models in our lives because we are evolved and trained to do just that. But models are most useful in normal times, where the inherent informational trade-off between modeling power and modeling comprehensiveness isn’t a big concern and where historical patterns don’t break. Unfortunately we are living in decidedly abnormal times, a time where simplifications can blind us to structural change and where models create a risk that cannot be resolved by more or better modeling! It’s not a matter of using a different model or improving the model that we have. It’s the risk that ALL economic models pose when a bedrock assumption about politics or society shifts. If you’re not prepared to look past your model…if you’re not prepared, as Steinbeck wrote, to separate your observations from your preconceptions…then you have a big invisible risk in your portfolio.

I know it’s hard to embrace what I’m describing as a profound agnosticism about the mechanics of how the world works. I know it goes against our biological grain to reject the comfort and succor of a deterministic model and an Answer. In many respects, deep agnosticism is the ultimate Other. It is a non-human perspective on how to think about the world – a Rakshasa – and I’m not expecting it to receive a warm or trusting welcome, particularly when it has the skin of some familiar investment product. But I think it’s the right way to look at a world wracked by political fragmentation, saddled with enormous debts, and engaged in the greatest monetary policy experiments ever devised by man. I think it’s the right way to look at a world of massive uncertainty, as opposed to a world of merely substantial risk, and it’s the perspective I’ll continue to take with Epsilon Theory.
A pitch-perfect example of Hayek's Fallacy in action. Just because something is complex doesn't mean you can just write it off as being complex.

And of course, espousing a "tyranny of the model" is a fundamentally anti-mathematical stance. The core problem he is heading towards--but his own preconceptions force him to miss (ironically enough)--is that it's not necessarily the model that's the problem, it's the inputs. Garbage in, garbage out, as programmers like to say.

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