Monday, November 03, 2008

PUMA Power

Paul Marston takes a look at how the PUMA factor is affecting the polling.

The results of the polls for President are all over the map. If the polls are supposed to be correct to a 95% degree of certainly give or take 2 or 3 percent, how can the polls be that much different for the same candidates when taken at the same time? The simple answer is that they should not be that far apart. If you take a look at the polls making up the average at on October 23rd, you will see a range from Senator Obama being up over McCain from 1 to 14 percent. Now there is such a thing called an outlier poll. That is where that other 5% comes into play and statistics says that the result could be outside of that normal sampling error of 2 to 3 percent. So let’s say that happened with both the 1% and 14% results and throw those away. That still leaves a range of 2 to 11% and that is way outside the margin of error on both polls. How come?

Take a look at the polling results for the 2004 election. Here you do not see the wild differences between the various polling firms. In the same time period in October of 2004, the range was from a 1 to 6 point lead for Bush. That is a five point spread and within the margin of error. That is a big difference between the current 13 point spread that is way outside the margin of error. To have this kind of spread indicates that something unusual is happening that is causing problems with the adjustments polling companies have to make to get the sample of voters to properly represent all of the voters. No random sample of voters perfectly represents all voters and polling firms have to weight their results to force them into being representative of all voters.
Of course they could reduce this adjustment by increasing the sample size by a factor of 10X. But then the polls start to cost real money. About 500 to 1,000 responses is considered a reasonable rate. Fairly good accuracy at a reasonable cost.
If their weighting algorithms are not correct, this would skew the results. Still, major national polling firms have a lot of experience and they have learned how to fine tune these algorithms pretty well. What is far more likely is that the sample simply does not accurately represent the voters in the area being polled as a whole due to some new factor. Obviously, when the polling companies look at the results from other polling firms and they see results different from their own outside the margin of error; they know something is amiss just like I do. This has caused them to try and tweak their weighting algorithms during the election season. Departing from tried and true weighting algorithms is a risky thing to do, but what choice do they have?

The fact of the matter is that instead of properly correcting for this unknown factor, they have only made things worse. I know of nothing else that could cause such wildly different results. This problem in turn has resulted in totally different headlines about what is happening in this election. Some say that the race is tightening considerably and others saying that the gap is widening to the point of being a landslide. The Drudge Report for October 22nd showed both of these claims. If you believe the Zogby results, then we are heading for a blowout. If you believe the Associated Press result, we are headed for another squeaker election. Obviously, they both cannot be right so which one is correct? That is precisely why the folks at prefer to average all the polls hoping that the various sampling errors will balance each other out.
Well that was a real hoot. The race is tightening/widening depending on who you believe.

What does McCain believe?
Meantime, back at the McCain camp, their strategy makes no sense. They have practically conceded Iowa, Colorado and New Mexico and are still pursuing some blue states. They are not overly worried about Ohio and Virginia either. Neither do they seem very worried about all of those toss up states. So what is going on here? Clearly, the McCain campaign thinks the narrowing algorithms are correct, but isn't that just wishful thinking? They pulled out of Michigan when the Democratic Rossman Group/MIRS poll had them down by only 5 points. Yet they persist in Pennsylvania when the RCP average has them down by 10.5 points. No one has them closer than 8 points right now and no one has had them closer than a tie in the last six months. They sent Palin to New Hampshire where they are behind from 8 to 13 points. Why would they do this? They cannot be that stupid unless they think they are on to something.

Remember that the McCain camp has their own polling firm and are running their own private polls. The only answer that makes sense is that the McCain folks are convinced that their own polling firm has figured out what factor is causing all those wildly differing results from the other polling firms. Whatever this factor is, it is something that the tried and true weighting algorithms are not handling properly. In a previous article, I speculated that it could be that the Bradley Factor is alive and well in this election. Since this is the first presidential election with a black candidate, the weighting algorithms are just not equipped to handle the race factor. The fact that the race card has been repeatedly played in this election could be causing the Bradley Factor to be much more prominent than it ordinarily would be.

Yet Gallup Polling claims that the Bradley Factor is a wash at best and could actually be adding an extra 3 points to Obama's total in a kind of reverse Bradley Effect. Looking at where the McCain folks are competing when they would seem to have no chance, they all have one thing in common. They were carried by Hillary Clinton and in some cases even after it was obvious that Obama had it locked up. McCain was bound to pick up some of Hillary's supporters anyway after the way Hillary was treated by the Obama campaign. These are the so-called PUMA (Party Unity My Ass) folks. Clearly the McCain folks think that there is a P.U.M.A. Factor in play which is a variation of the Bradley Factor. The results that Hillary got simply cannot be explained by race alone. It was the positions that she took that were different than Obama's that resonated with these voters. Because Obama has such an extremely liberal voting record, there were some issues where even Hillary agreed with McCain more than she did with Obama.
There is way more and you should read it all for it is good.

And then you should read his quantification of the PUMA factor at The McCain-Palin Landslide and How Big is the P.U.M.A. Factor?.

Cross Posted at Classical Values

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