How is it possible? Last night, I was wondering why Clinton isn't ahead by 50 points, considering the way the press has been reporting lately. But the press is skewed, trying to shape what we do, and we're only entering the last phase when reputations are on the line and media risk looking like fools if something happens that seems to blindside them.
A mere 7 days ago, Bloomberg Politics had Clinton with a 9 point lead. And pollster J. Ann Selzer was saying: "This poll shows movement toward Clinton with all the right groups it takes to win—including men and those without a college degree. Their alignment with Clinton is a formidable change in the algebra."
Is Bloomberg Politics a screwy polling operation? I found an article by Nate Silver from last August, "Election Update: When One Poll Makes A Big Difference" — the one poll that made a big difference was Bloomberg Politics and it made a big difference because Silver's model weights the different polls based on their quality, and Bloomberg Politics is one of his high-quality polls:
By “high quality,” I mostly mean a poll with a high pollster rating — which are based on a pollster’s past accuracy and methodology — since the trend line adjustment puts more weight on better-rated polls. Selzer & Company (which also conducts the prestigious Des Moines Register Poll) more than qualifies: It’s one of just six polling firms with an A-plus rating from FiveThirtyEight.Silver added:
There’s another, more subtle dimension to this also, which is that Selzer hasn’t polled the general election very often this year. (Just the three national polls so far.) The trend-line adjustment is therefore designed to give a lot of weight to a Selzer poll whenever it weighs in. By contrast, it gives less weight to any given poll from a pollster that surveys the race frequently, such as by conducting a national tracking poll.Well, Selzer weighed in today, and the trend line is wild — an 11-point change in one week. [ADDED: Again, as noted above, I think I misread the text at Politico.]