Is 99% a reasonable probability?
http://election.princeton.edu/2016/11/06/is-99-a-reasonable-probability/#more-18522
Three sets of data point in the same direction:
- The state poll-based Meta-Margin is Clinton +2.6%.
- National polls give a median of Clinton +3.0 +/- 0.9% (10 polls with a start date of November 1st or later).
- Early voting patterns approximately match 2012, a year when the popular vote was Obama +3.9%.
Based on this evidence, if Hillary Clinton does not win on Tuesday it will be a giant surprise.
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An obvious contrast with PECs calculation is the FiveThirtyEight win probability, which has been in the 60-70% range. As a prominent outlier this season, FiveThirtyEight has come under fire for their lack of certainty. Its founder, Nate Silver, has fired back.
Let me start by pointing out that FiveThirtyEight and the Princeton Election Consortium have different goals. One site has the goal of being correct in an academic sense, i.e. mulling over many alternatives and discussing them. The other site is driven by monetary and resource considerations. However, which is which? Its opposite to what you may think.
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With all that prelude (whew!), let me explain how the Princeton Election Consortium achieves such a high level of confidence.
Much more at the link.