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Looking for Super Tuesday Exit Polls?

Topics: 2008 , Exit Polls

Looking for leaked exit poll results from the Super Tuesday states? As regular readers know, the leaks of exit poll we experienced in 2004 and prior years have been stopped, as the the network consortium that conducts the exit polls now restricts access to a small number of analysts in a "quarantine room" for most of the day and did not release the results to the networks and subscriber news organizations until 5:00 p.m. eastern time. While some of that information will leak a leak, that process will remain in place today (Tom Webster, an employee of Edison Research, has blogged some details about life inside the quarantine room).

What this means (and those of you who play the various election "futures" or predictions markets should listen closely) is that any "exit poll" numbers you hear about before 5:00 p.m. are bogus (or at least, not produced by the networks).

Here are a few tips for making sense of the exit poll data you will see tonight (a slightly edited version of tips I posted on the morning of the New Hampshire primary, with a few edits):

1) An exit poll is just a survey. Like other surveys, it is subject to random sampling error and, as those who follow exit polls now understand, occasional problems with non-response bias. In New Hampshire (in 1992) and Arizona (in 1996)* primary election exit polls overstated support for Patrick Buchanan, probably because his more enthusiastic supporters were more willing to be interviewed (and for those tempted to hit he comment button, yes, I know that some believe those past errors suggest massive vote fraud -- I have written about that subject at great length).

2) The networks rarely "call" an election on exit poll results alone. The decision desk analysts require a very high degree of statistical confidence (at least 99.5%) before they will consider calling a winner (the ordinary "margin of error" on pre-election polls typically uses a 95% confidence level). They will also wait for actual results if the exit poll is very different from pre-election poll trends. So a single-digit margin on an exit poll is almost never sufficient to say that a particular candidate will win.

3) Watch out for "The Composite." As they have for the earlier primaries, we expect the web sites of CNN, MSNBC and CBS to post exit poll tabulations shortly after the polls close that will update as the election night wears on (we will post links and commentary here, so we hope you'll plan to check back in later tonight). Those data are weighted to whatever estimate of the outcome the analysts have greatest confidence in at any moment. By the end of the night, the tabulations will be weighted to the official count. Typically, the first waves of exit poll tabulations (including most that leak before the polls close) are weighted to something called the "Composite Estimate," a combination of the exit poll data alone and a "Prior Estimate" that is based largely on pre-election poll results. So if you look to extrapolate from the initial tabulations posted on MSNBC or CNN (as we have done here at Pollster each primary night this year), just keep in mind that in the estimate of each candidate's standing in the initial reports will likely mix exit poll and the pre-election poll estimates (not unlike the kind we report here).

Finally, if you would like more information on how exit polls are conducted, you may want to revisit a Mystery Pollster classic: Exit Polls - What You Should Know. Happy Super Tuesday!

Update: We're live blogging tonight with overall candidate estimates derived from the public exit polls.

 

Comments
Korn:

Your site is excellent!! non-bias of course unlike the others

Great job everyone...

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KG2V:

Hi Mark,
Good luck to you guys over at NBC - going to be a LONG night

Charlie
(who runs some of the computers at one of the other NEP members)

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Alan:

OK, I'm serious here, why does anyone even care about exit polls? Just wait a few hours and find out the real results. This is truly a waste of time and effort that could be expended doing something useful.

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Jeff:

The real value of the exit polls comes from the internal data, which you can't deduce from the election results. Tells you what demographics voted for which candidate, why, and when they made up their minds. Very useful survey research, even if the "projected winner" numbers are quickly dismissed.

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I care about exit polls.

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June:

Exit is important data when voting machine was tampered. Given that there are many ways to hack a voting machine (see http://www.hackingdemocracy.com/), it is extremely important that we have exit poll as a verification.

In 2004, Ohio went to Kerry as predicted by exit poll. But voting results came out the opposite. It was then discovered that 80,000 votes for Kerry were counted instead for Bush. That alone is a swing of more than 160,000 votes -- enough to have put John Kerry in the White House.

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Mark Blumenthal:

Just a note: We're live blogging tonight with overall candidate estimates derived from the public exit polls. Ask your questions there and I'll try to answer...

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Jeff:

June, please read what Mark Blumenthal has written about exit polls and Ohio. You can click through from his post above. He knows an enormous amount about this subject, and can explian why an exit poll does not in any way "verify" the election returns.

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dan:

Has the Clinton Machine won yet?

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Onlooker:


As always very informative.

I notice that many analysts draw broad conclusions based on exit polls. As you say, it is a little murky to draw such conclusions especially when the numbers are close. Last night, the numbers for MO, NM, AZ, and CT were close. These numbers were used to journalists to state things that are questionable. Examples include, how MO was a great victory for Mr. Obama or how CA was a minor victory for Mrs. Clinton. Of course, both of them did quite well.
By the way, we have the answer to the CA polls (by Zogby).

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Don Smith:

This is all ridiculous. EXIT POLLING AND ELECTION PREDICTING SHOULD BE BANNED. NO RESULTS OF ELECTIONS SHOULD BE REPORTED UNTIL ALL POLLS AROUND THE COUNTRY HAVE CLOSED!!!! Even better, all voting results should be sent to a government voting office for tabulation and then distributed to the various media for reporting. WE NEED TO END THE MEDIA'S CONTROL OF OUR ELECTIONS!!!!

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JW:

Exit polling only provides a means for division. Instead of breaking voters down by race, why can't we all be people. Does it matter which age bracket voted for who? Instead of reaching out to a particular sect of voters, candidates should reach out to the country of voters as a whole.

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Anonymous:

where are the bar graphs?

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