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You're all over this thread with the same comment, and you're wrong. When an outcome has 60% likelihood of occurring, then it should occur 6 out of 10 times. B

by jmilloy 14y ago

You're all over this thread with the same comment, and you're wrong. When an outcome has 60% likelihood of occurring, then it should occur 6 out of 10 times. But the election only happens once. The prediction isn't "wrong" when the outcome occurs 1 out of 1 time. In this case, you describe 10 separate events, each with 60% chance that a certain outcome occurs. So we have 10 separate outcomes that occurred 1 out of 1 times.

danielweber 14y ago
But the election only happens once. The prediction isn't "wrong" when the outcome occurs 1 out of 1 time. It's not a single event. Nate Silver made many many predictions about last night. And none[1] of them were binary up-down events. If he did make binary predictions, we could claim he got them "all right," but Silver was never doing that in the first place. Nor am I saying he should have. Try this: if Romney had won, would it mean that Nate Silver was wrong? Should we say, like Silver's critic Dylan Byers did, "it’s difficult to see how people can continue to put faith in the predictions of someone who has never given that candidate anything higher than a 41 percent chance"? No, we shouldn't. Because Silver didn't say "Obama would win." He said "Obama has a ~86% chance of winning." Silver gave a 14% chance of finding himself in a universe where Romney would win despite what his data was telling him. Silver made essentially no prediction about Florida -- and we shouldn't push him into making an up/down decision if he doesn't think he can. But everyone wants to force him into the binary prediction box. EDIT: took out snark [1] Okay, he was 100% on some states like New York, but so was everyone else, so those aren't interesting to talk about.
- jmilloy 14y ago
  Ha! I've been thinking about this pretty hard and talking to a colleague at work, and changed my mind. You're right... he's not making predictions, he's making forecasts. And you can't say that a forecast was "right" or "wrong" based on which side of the forecast any one result landed. Assuming the n isn't just too small to say anything, the only two reasonable conclusions to choose between are a) in this set of events, the outcome in EVERY state happened to be from more likely side of the forecast, which together is unlikely, or b) Nate's forecasts are inaccurate, being skewed much more to the middle than they ought to be. Also, "all over this thread" was just meant to imply that I noticed the same comment from you more than once. Sorry for not being more specific.

by jmilloy 14y ago

danielweber 14y ago

But the election only happens once. The prediction isn't "wrong" when the outcome occurs 1 out of 1 time. It's not a single event. Nate Silver made many many predictions about last night. And none[1] of them were binary up-down events. If he did make binary predictions, we could claim he got them "all right," but Silver was never doing that in the first place. Nor am I saying he should have. Try this: if Romney had won, would it mean that Nate Silver was wrong? Should we say, like Silver's critic Dylan Byers did, "it’s difficult to see how people can continue to put faith in the predictions of someone who has never given that candidate anything higher than a 41 percent chance"? No, we shouldn't. Because Silver didn't say "Obama would win." He said "Obama has a ~86% chance of winning." Silver gave a 14% chance of finding himself in a universe where Romney would win despite what his data was telling him. Silver made essentially no prediction about Florida -- and we shouldn't push him into making an up/down decision if he doesn't think he can. But everyone wants to force him into the binary prediction box. EDIT: took out snark [1] Okay, he was 100% on some states like New York, but so was everyone else, so those aren't interesting to talk about.

jmilloy 14y ago
Ha! I've been thinking about this pretty hard and talking to a colleague at work, and changed my mind. You're right... he's not making predictions, he's making forecasts. And you can't say that a forecast was "right" or "wrong" based on which side of the forecast any one result landed. Assuming the n isn't just too small to say anything, the only two reasonable conclusions to choose between are a) in this set of events, the outcome in EVERY state happened to be from more likely side of the forecast, which together is unlikely, or b) Nate's forecasts are inaccurate, being skewed much more to the middle than they ought to be. Also, "all over this thread" was just meant to imply that I noticed the same comment from you more than once. Sorry for not being more specific.