… There’s been a lot of news over the past two weeks — the conclusion to the FBI’s investigation into Clinton’s emails and the Dallas shootings of police officers, in particular — and it would be nice to see how the polls settled in after a couple of slow weeks on the campaign trail. However, we’re entering a period of rapidly moving political news. … The prospects definitely look better for Trump than they did a week or two ago, but the landscape also looks blurrier, and it may not be until mid-August that we have a chance to catch our breath.
So for the rest of this article, I’m going to focus mostly on the Quinnipiac polls — both to explain why our model reacted relatively strongly to them, when some of the other data wasn’t so bad for Clinton, and as an example of how you might think about “unexpected” polling results as they arise over the next few weeks. CONT.
Nate Silver, FiveThirtyEight