3 ms·

Can you briefly summarize what distinguishes foxes vs. hedgehogs?

• jacques_chester 14y ago
  It comes from an essay by Isaiah Berlin, The Hedgehog and the Fox. Hedgehogs know "one big thing" and Foxes know "lots of little things". In the expert prediction study, experts who had a universal framework which they extended rigidly to every problem performed poorly on both calibration (correlation of confidence and actual post-factual probabilities) and discrimination (correlation of more/less/same predictions to actual outcomes). Foxes tended to throw together a bunch of thoughts, including from incompatible theories, express a lot of "one of the one hand, and on the other" sort of thinking and qualified most of their predictions. They did much better on calibration and somewhat better on discrimination. Basically, Hedgehogs tend to make more extreme predictions ("Russia will fall into civil war by 1997") more confidently ("it's almost certain") than Foxes. But statistically, about 40% of the time variables in the complex systems being forecast actually stayed within a band and neither decisively moved up or down. I know that you're probably thinking of holes and objections to the study already -- read the book. Tetlock and his collaborators were astonishingly thorough in trying to deal with all the relevant arguments and counterarguments with actual data.
  • cbsmith 14y ago
    > I know that you're probably thinking of holes and objections to the study already Quite the contrary. Your description of the differences is clear and the outcomes from the study fit well with a similar meme in machine learning around ensemble methods.