For the individual prediction it's impossible to say, so you reward the people who got it right based on how likely they said it was, and you penalize the people who got it wrong based on how unlikely they said it was. If we apply a proper scoring rule, over time the you score better by giving better calibrated guesses.
I agree with this. But the original statement is poorly phrased, that "He was right." He was perhaps more right than others who gave Trump lower odds. But there's not an absolute right/wrong (unless someone gave 100:0 odds).
He seems to have been right that Trump's odds were higher because prediction error for different states wasn't independent as some other models were assuming.
I agree that we don't have a way of assessing whether the percentage given was "correct", but over a bunch of predictions we can keep track and see how he does when he gives various percentages, or compare against others with a proper scoring rule.
I don't make any claim that the odds he gave were right, but just that if they were we should still expect to see his "prediction" be wrong pretty often, so the fact that his prediction was wrong this time only counts so much against him (and to make up for that, only counts so much in is favor if he's right with low confidence).
You’re being downvoted by people who don’t have a good argument against you
To them Silver could have said Trump had a 1% chance of winning, and they would still be saying “yOu dOnT uNdErStaNd stAtIstIcS!!1”
Basically, a lot of people really really really wanted to believe Hillary winning was a sure thing. They ignored any and all data saying “maybe she won’t”
And now you can see the effect looking back - these people are still so salty about that bitter loss that they come in here and say that giving Trump a <30% chance of winning was absolutely the right call and if you don’t see that then you’re an idiot who can’t grasp statistics
Literally - half the comments responding to me was this vitriolic idiocy. They can’t think, they’re emotions have overridden that
That’s why they downvoted you for accurately pointing out that there’s no such thing as knowing that a statistical guess was “right”
They’re downvoting you because you upset them by making them accept reality. That they were wrong and the Hillary couldn’t win.
A pollster claiming Trump:Hillary at 99:1, 50:50, or 33:66 could all claim to have been "right".