
Nate Silver’s Lessons for Big Data from the Unpredicted Trump Victory - DataDiva
http://thenewstack.io/lessons-big-data-unpredictability-trump-win/
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NumberSix
The USC Dornsife/LA Times Daybreak Election Poll

[http://www.latimes.com/politics/la-na-pol-usc-latimes-
poll-2...](http://www.latimes.com/politics/la-na-pol-usc-latimes-
poll-20161108-story.html)

did a significantly better job than Nate Silver and 538 in estimating the
level of Donald Trump support.

~~~
ZeroGravitas
No it didn't, it overestimated the popular vote too much in his direction and
was off by about 5 points. Most polls were better than that.

[http://thehill.com/blogs/pundits-blog/campaign/315145-one-
la...](http://thehill.com/blogs/pundits-blog/campaign/315145-one-last-
look-2016-polls-actually-got-a-lot-right)

Since the 538 stuff is mostly a summary of all of those other, better polls,
they got the popular vote pretty much bang on. Their modal of how that
translated to the electoral college was better than any other model too.

Except for the "Donald Trump will win the popular vote, therefore he'll
definitely win the electoral college, oops he didn't win the popular vote, but
let's just pretend we're polling the electoral college instead" model.

~~~
NumberSix
USC Dornsife picked the winner. Other polls did not.

Trump got 46.1 percent of the popular vote:

[http://www.cnn.com/2016/12/21/politics/donald-trump-
hillary-...](http://www.cnn.com/2016/12/21/politics/donald-trump-hillary-
clinton-popular-vote-final-count/)

That is almost the same as the 46.8 percent of the popular vote for Trump that
USC Dornsife predicted. Pretty close to spot on.

The other polls, including 538, underestimated the size of Trump's support.

~~~
ZeroGravitas
It had Clinton a) losing the popular vote, and b) at 43.6%, a prediction of
-3.2 points behind Trump versus a reality of +2.1 to Clinton, giving a total
miss of 5.3% when other polls got much closer and got the popular vote winner
correct.

538 did not conduct polls, only aggregate other people's. And as I said, those
polls, and 538's aggregate of them correctly predicted Trump's support,
including the fact that it was less than Clinton's.

~~~
jakeogh
"only aggregate other people"... and apply a "weight" to each. Not that he
shouldn't, most of the polls were push polls. I got a real kick (and a nice
check from predictit) out of the AZ polls showing H ahead by using a ~20% dem
over-sample.

~~~
ZeroGravitas
Yes, they weight the polls, and in doing so got a very accurate results for
the popular vote.

Individual state polls had more variance than the national polls, but those
were wrong in both directions, both over and understating Trump's support,
mostly depending on the number of less educated white people in the state, who
were apparently hard to poll, or to estimate their likelihood to actually
vote.

Both you and the other poster seem to be trying to create a narrative that
Trump's popular support was underestimated, when really it's just the
interaction of where his support was and the electoral college system that
fooled most models, though notably not the 538 model, which gave Trump a
decent shot at winning. Btw, you almost certainly don't know what an
"oversample" is, you should read up on that, as you use the phrase as if it is
some devious way to skew the polls in one direction. Actually, while I'm on
the topic, you seem to have got the wrong end of the stick about what a push
poll is too. Those are devious, but do the really apply here. Just a Wikipedia
summary should be enough to set you on the right path.

~~~
jakeogh
"accurate results for the popular vote" is irrelevant for good reasons.

~~~
ZeroGravitas
I think you're in the wrong thread, this one is about who "did a significantly
better job than Nate Silver and 538 in estimating the level of Donald Trump
support", not who would win the electoral college.

~~~
jakeogh
Funny, because that's the only level of support that matters. 538 got it wrong
where it counts.

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DefaultUserHN
The biggest problem with Nate Silver was that he was a victim of fake news. He
got caught up in the fake news, believing that Trump have no chance.

Anybody who actually went to a Trump rally would see with their own eyes, that
what Trump said was totally different from what the TVs claimed he said. They
could see that the whole media was lying about Trump.

If Nate Silver had went to just one Trump rally, he would have seen that too,
and he would have known that Trump was going to win. Would have been able to
tweak his data set, and would have made a better prediction.

