Friday, October 26, 2012

Sam Wang as the Perfect Antidote for Romomentum

 By Evil Sax/Diary of a Republican Hater

It's funny because Nate Silver has gotten a reputation among conservatives as being biased towards Obama. For those of you who read Nate regularly that may be news for. Indeed, I would not call him very bullish for the President. Even now when there is plenty of data to make the case-based on his own model-that Romney's bounce has been over since October 12, the most he could say is that it seems to have stopped.

   I think it's safe to say that he's been very conservative this cycle as other poll analysts argue:

   "From this perspective, it’s a bit odd to see commentary out there suggesting that Romney should be favored, or that quantitative, poll-based analyses showing Obama ahead are somehow flawed, or biased, or not to be believed. It’s especially amusing to see the target of this criticism be the New York Times’ Nate Silver, whose FiveThirtyEight blog has been, if anything, unusually generous to Romney’s chances all along. Right now, his model gives Romney as much as a 30% probability of winning, even if the election were held today. Nevertheless, The Daily Caller, Commentary Magazine, and especially the National Review Online have all run articles lately accusing Silver of being in the tank for the president. Of all the possible objections to Silver’s modeling approach, this certainly isn’t one that comes to my mind. I can only hope those guys don’t stumble across my little corner of the Internet."

    For some sense of centering, or reality, you might want to give Sam Wang's Princeton Consortium-or for that matter, of course, Votomatic. Here is a great post where Wang takes on the mightiest analyst around: you guess it, David Brooks. It seems Brooks has spent hours poring over polls trying to get to what they are saying. Wang, however, is less than overwhelmed by his conclusion:

    "It was fun to learn of David Brooks’s addiction to polling data. He spends countless hours on them, looking at aggregators, examining individual polls, and sniffing poll internals. From all of this, what has he learned?

  1. Today, President Obama would be a bit more likely to win.
  2. There seems to be a whiff of momentum toward Mitt Romney.
    (Emphasis mine.)

     "I am having a sad. All of that effort, and his two conclusions still have two major errors. Evidently he does not read the Princeton Election Consortium."

       More than evidently, I suspect it's all but a surety he doesn't. Wang corrects number 1. Obama is not "a bit more likely to win"; he's actually much more likely to. See what I mean about Nate: he's actually something of an outlier among the poll geeks:

       "This is false – he’s a lot more likely to win."

       "In a race today, President Obama would win with about 90% probability. The true probability is even higher, since the Meta-Analysis does not correct for individual pollster errors. We could – but the political blowback from unskewing polls is too large."

        Next he calls out Romomentum:

        "Ro-mentum ended around October 11th, the date of the VP Biden-Ryan debate and reversed around October 16th, Debate #2. Now the median EV expectation is at a plateau around Obama 293 EV, Romney 245 EV. Viewed through the all-important Electoral College, Obama has a Popular Vote Meta-Margin lead of 1.5%. This measure is precise to within <0 .5=".5" a="a" any="any" anything="anything" better="better" bit="bit" br="br" far="far" if="if" is="is" look="look" poll.="poll." race="race" single="single" starting="starting" static.="static." than="than" the="the" to="to">
         "In President Obama’s favor, he (a) won debate #3, and (b) has had a Meta-Margin lead of +3.3+/- 1.3% this year. Movement is more likely toward this mean than away from it. The red strike zone in our history graph reflects this, and gives a re-elect probability of 89%."

          Finally, Wang finishes with this advice: Don't be like David Brooks. I'd say that if you follow that rule when you do any kind of political analysis you can't go wrong. This advice is a general principle to always keep in mind.

          "Don’t be like David Brooks. Finally, a word on examining individual polls. In the comments section, I am seeing breathless statements like how the TIME poll shows Obama +5% in Ohio, and won’t that move the Meta-Margin, and so on. Hey…relax. In case you haven’t noticed, the Meta-Margin’s not moving that much. Try to avoid caressing those individual polls too much!"

           So next time you are reading some banal post about Romentum or even tired of Nate Silver's ultra careful predictions you might want to give him a try.
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