27 DEC 2013 by ideonexus
Why Economists Will Continue to be Wrong
Carter had initially used arbitrary parameters in his perfect model to generate perfect data, but now, in order to assess his model in a realistic way, he threw those parameters out and used standard calibration techniques to match his perfect model to his perfect data. It was supposed to be a formality--he assumed, reasonably, that the process would simply produce the same parameters that had been used to produce the data in the first place. But it didn't. It turned out that there were many ...
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They make models based on past data, and when they fail to predict the future, they adjust them to match the new past data. The problem is that so many models will match the past data, there could be no end to the number of models they throw out.
