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by jazzyjackson 2381 days ago
When a thousand hedge funds hire mathematicians and economists to create models of the global economy so that they can predict whether individual stocks will move up or down over different timescales, their task is similar to predicting the weather. Some will beat the market, many won't. Are they guessing?

Maybe that's a bad analogy, but my point is that climate is a chaotic system, and detailed models might be right and might be wrong. It's not that the scientists are guessing, of course the science is methodical - but the performance of the model might not be better than guessing, hence the speculation of survivorship bias. There were lots of climate models over the last century, was there consensus around a paper that is now proven correct? Or were there a hundred models that were off and one that, yes, happened to be correct. I don't know the answer.

1 comments

I think an individual stock in this analogy would be "Will it rain in Duluth". Climate predictions, to use your economic model, would be more along the lines of "Will stocks continue to rise on the whole over the next 100 years?"