The Mathematics of Poll Skewing: By: Joe Wallace

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Joe Wallace, Coachella Valley iHub

The Mathematics of Poll Skewing:

The vast differences in polls that are being reported both nationwide and in toss-up states have drawn significant attention from both sides of the political fence. In past elections polls have seldom been accused of being skewed to change people’s votes but this year such allegations have been tossed from both sides.

Today’s Real Clear Politics average uses polls that show a 7% difference in the national presidential election with Rasmussen calling the race a tie and the National Journal having President Obama leading by 7%. It is clearly impossible for both of these polls to be correct and the margin by which they vary makes it clear that their sampling patterns or their voter turnout models are dramatically different.

The term voter turnout models for those new to poll skewing is the assumption of what the turnout of voters will be by party on election day. The purpose of this article is to take a real world example and show how the same data with different assumptions leads to quite different results. All of the data chosen for this article comes from the highly respected polling firm Gallup.

Current Gallup data from the trailing 3 weeks indicates that 93% of Democrats will be voting for President Obama and 4% will be voting for Mitt Romney leaving only 4% undecided. Similarly with Republicans 92% express support for Mitt Romney, 5% support the President, and 3% are undecided. Among those describing themselves as Independent 44% support Romney, 43% are in the President’s camp, leaving 13% who have not yet decided.

Gallup is still using registered voters in the polls they report but they do keep a separate accounting of likely voters and typically change their reporting as the election gets closer. Just prior to the 2012 election the registered voter turnout model for Gallup was 32% Democrats, 31% Republicans, and 33% Independents. When looking at the average for likely voters on the very same day according to Gallup the numbers were 30% Democrats, 37% Republicans, and 30.5% Independents.

If one does the math using the registered voter turnout model for Gallup in 2010, President Obama leads Mitt Romney by a margin of 45.5% to 44.5%. When the average of likely voter turnout model is used the tables are turned and Mitt Romney has a lead of 48.7% to 42.9%. Amazingly the change in the poll just by going from registered voters to likely voters with Gallup’s turnout models is a full 7%.

Of course the undecided are still at 6.2% and the overwhelming majority of those are Independents.

The importance of this analysis is simply that by making small variations in the assumptions used in the voter turnout model pollsters can essentially get the answer they are looking for. The Rasmussen poll always uses likely voters and bases its assumptions on previous turnouts and voter indications. Gallup uses registered voters until Election Day approaches and then shifts to likely voters. Other polls use registered voters which tend to oversample Democrats by roughly 4%. Still others make up their own models seemingly from the thin air with some recognized names oversampling Democrats by as much as 11% which is 4% higher than even the 2008 Presidential election when then candidate Obama turned out more Democrats than any election in history.

The only real conclusions that one can draw right now is that pollsters have agendas and are hiding behind the legacy of legitimacy that their organizations claim to have. With the variance in assumptions of the turnout models and the over 6% that are undecided the current election is not in the bag for either candidate.

Gallup Voter Turnout Model: October 4, 2010

http://www.gallup.com/poll/143363/gop-positioned-among-likely-midterm-voters.aspx

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8 COMMENTS

  1. Yes, I know the polls are skewed. I know that Mitt Romney is really ahead by a gazillion percent in every poll, once you “unskew” the polls.

    And, yes, I know the liberal media is at it again, conspiring to depress GOP turnout by concocting polls that put Obama ahead nationally and in swing states.

    And, yes, I know that Obama’s Justice Department and David Axelrod have put the squeeze on Gallup, and that’s why the Gallup tracker has suddenly shot up to Obama +6.

    And, yes, I know that somehow, Rupert Murdoch has joined the conspiracy, either because he is a traitor to the conservative cause, or, more likely, because he has been threatened by Eric Holder over the phone hacking scandal, and that’s why the latest Fox News poll and the most recent Wall Street Journal poll both have Obama +5.

    And, yes, I know that the conservative powerhouses on Fox News like Sean Hannity, Bill O’Reilly, paid consultant Karl Rove, Brett Baier and the wholesome crew from “Fox and Friends” have been heroically calling out these biased and skewed polls, exposing them for the frauds they truly are. (And how wise of these heroes to avoid charging their own boss with participation in the conspiracy, knowing full well that Rupert Murdoch “has a gun to his head” from Obama’s nefarious DOJ!)

    So, yes, I will admit that Romney is on the verge of an enormous, sweeping win that will shock Democrats who believe in statistical science like poll aggregates and in historical polling trends in presidential races.

    But to my conservative friends who know that all of the above statements are stone, cold facts, I have a few, simple questions:

    If all that is true, why are so many in GOP leadership in full panic mode regarding Romney’s campaign?

    Why are some top GOP officials (unnamed, of course) calling Wednesday night’s first presidential debate in Denver “do or die” for Mitt Romney?

    Why has the Romney campaign been in “retooling mode” for weeks now, with one attempted makeover after another?

    We all agree, the polls are skewed! Romney is sailing to victory!

    Is all of this angst among your leadership just part of an incredibly shrewd and diabolical plot to make Democrats overconfident and to set them up for crushing disappointment on election night?

    And are all of you in on this plot, too, with your foaming-at-the-mouth rants on message boards every time a new poll is announced showing Obama surging to a measurable lead, nationally and in swing states?

    Is this all one, giant set-up?

    Damn! I knew it! I knew you were all brilliant strategists. Every last one of you.

    The one thing that puzzles me… How do you keep the memos secret?

    • You have an imagination that is even more vivid than the foaming at the mouth talking heads on TV named Hannity and Maddow. Try the sensitivity analysis yourself. You will see how easy skewing a poll is using the same raw polling data. It is a simple first derivative of the turnout algorithm.

      • +2 for naming Hannity in the group. I watch Bill O’Reilly on a regular basis so I can see alternate points of view. But I cannot stand Hannity. His voice sends me over the edge

  2. Right-wingers need ‘skewed polls’ conspiracy theory for Romney to win (and even more if he loses)

    Listening to you and other right-wing zealots, you want readers to believe the entire political science establishment, in cahoots with mainstream media, are circling their wagons around their favored candidate, and obscuring either the inevitability of his failure or a more sinister outcome behind a font of false information. The current polling numbers that show President Barack Obama pulling ahead of Republican presidential candidate Mitt Romney are cooked, you say.

    It’s a laughable premise. The media are hardly kind to liberals or Democrats, but this is no random theory dreamed up by an unhinged wing nut. It’s you and the rest of the right wing carefully crafting a narrative, and one that may hold the only hope Republicans have of winning the 2012 presidential race. Why? Because with an increasingly shrinking slice of the electorate undecided on its presidential candidate, the outcome of election 2012 will likely hinge almost entirely on which candidate gets to the polls all the voters who lean his way. Polls that depress the spirits of right-wing voters could easily depress their turnout, as well.

    In the alternate universe occupied by the right, there’s a dark conspiracy afoot, one in which the steadfast conservative exists in an world that conspires to confound him with unwelcome information. To those like you with the paranoid, xenophobic mindset it’s hardly a stretch to believe it when you’re told that the very polls that are used by media to assess the state of political contests are skewed to favor the liberal candidate, especially when the candidate is a black man named Obama.

    Although you have now started hammering the bad-polling-model theme for weeks, you are just furthering your slide into disrepute by giving “credit” the whack-job website called UnskewedPolls.com, based on the notion that nearly all the national polling operations were including too high a percentage of self-described Democrats in the sample groups that pollsters use as their stand-ins for the total electorate when doing their surveys.

    If pollsters were including too many Democrats in their sample groups, goes your reasoning, then all those surveys by major polling operations showing Obama breaking ahead? Wrong, wrong, wrong. In fact, your flawed theory is that when you “unskew” those polls, Romney is winning big in the alternate universe.

    But your “theory” has a LOT of problems. Your determination of the percentages of Democrats and Republicans you believe should be reflected in a polling sample rest on a cherry-picked data point: the percentage of self-described Democrats and Republicans from a single day of a tracking poll conducted by Rasmussen, an organization whose polls traditionally skew Republican.

    The number one reason for the “skewed polls” narrative is your pathetic need to create a high level of right-wing turnout in early voting and on election day.

    Most chillingly, should Romney lose the election, the result of such a conspiracy theory will be to cast doubt on the outcome of the election itself, reinforcing the false notion, ever popular on the right, that the presidency of Barack Obama is not constitutionally legitimate. In the mind of the unhinged, that’s a license to violence.

  3. Had to fight this guy with one hand tied behind our back in 2008 because the PC crowd demanded it. The outcome was predictable.

    It was reasonable to surmise that after the majority of the country realized, by his failed performance on the job, that he was truly not ready to handle the office, we could dispense with all the PC crap this time around. Not to be though. He fights like a street thug, but is the first to start howling when the tables are turned.

    I am convinced of one thing, that he is no leader. I wouldn’t follow this guy anywhere. If the public is dumb enough to vote him in again, then I will know that affirmative action is still alive and well and extends to the highest office in the land.

    ___

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