The Volokh Conspiracy - How Exit Polling Works in 2006 at Pollster.com.--

There is a great description of exit polling at Pollster.com:

A quick summary of how exit polls work: The exit pollster begins by drawing a random sample of precincts within a state, selected so that the odds of any precinct being selected are proportionate to the number that typically vote in that precinct. The National Election Pool (NEP) consortium, which is conducting the exit polling for the six major networks, will send exit pollsters to more than 1,000 precincts across the country today. . . .

The selected voters receive a one-page paper questionnaire to fill out. In the past, the questionnaire included approximately 25 questions (see an example from the 2004 exit polls), although this year the exit pollsters have worked to prepare a shorter questionnaire. Respondents fill out the survey privately then place it in a clearly marked "ballot box" so they know their identities cannot be tracked and their answers remain confidential.

The logistics of transmitting all the results to a central location quickly and accurately provides the biggest challenge. To facilitate the process, interviewers will take a 10 minute break during the day to tabulate responses. Interviewers have typically stopped to call in their tabulations at three approximate times during the day: 9:00 a.m., 3:00 p.m. and shortly before the polls close. . . .

After the polls close, the network analysts also begin to look at estimates based on larger samples of approximately 2,000 randomly selected precincts where NEP personnel obtain official vote tallies as they become available. The networks typically use this larger system of tabulations and estimates — rather than the exit polls alone — to call close contests after the polls close. But when the vote is really close, as it is likely to be tonight in states like Missouri and Virginia, even the larger samples of hard returns will be inadequate. The analysts will have to watch the complete vote count, just like the rest of us.

In years past, hundreds of producers, editors and reporters would have access to the mid-day estimates starting at about noon, and preliminary exit poll cross-tabulations (like this one) would inevitably leak out. This year the networks have taken steps to prevent such leaks, creating a "Quarantine Room" where, as the Washington Post's Howard Kurtz reports, "two people from each of the networks and the Associated Press" will be allowed "entree to a windowless room in New York [where] all cellphones, laptops and BlackBerrys will be confiscated. The designated staffers will pore over the exit polls but will not be allowed to communicate with their offices until 5 p.m."

So there you have it folks. At 5:00 p.m. the data will be flowing to newsrooms as it always does and the usual leaks will presumably commence shortly thereafter. One rationale for the delay is that the data available at that hour will be more representative and not just based on those who vote in the morning.

So if this process is so sophisticated and the late afternoon numbers are better, why can't we rely on the leaked "numbers" that will undoubtedly leak after 5:00 p.m. today?

1) It is still just a survey . . . .
2) Early or absentee voting . . . .
3) Past Errors favored Democrats . . . .
4) Limited Data on the House elections . . . .

Expect heavy hinting by the networks after 5pm ET today.

	[Jim Lindgren, November 7, 2006 at 2:43pm] Trackbacks How Exit Polling Works in 2006 at Pollster.com.-- There is a great description of exit polling at Pollster.com: A quick summary of how exit polls work: The exit pollster begins by drawing a random sample of precincts within a state, selected so that the odds of any precinct being selected are proportionate to the number that typically vote in that precinct. The National Election Pool (NEP) consortium, which is conducting the exit polling for the six major networks, will send exit pollsters to more than 1,000 precincts across the country today. . . . The selected voters receive a one-page paper questionnaire to fill out. In the past, the questionnaire included approximately 25 questions (see an example from the 2004 exit polls), although this year the exit pollsters have worked to prepare a shorter questionnaire. Respondents fill out the survey privately then place it in a clearly marked "ballot box" so they know their identities cannot be tracked and their answers remain confidential. The logistics of transmitting all the results to a central location quickly and accurately provides the biggest challenge. To facilitate the process, interviewers will take a 10 minute break during the day to tabulate responses. Interviewers have typically stopped to call in their tabulations at three approximate times during the day: 9:00 a.m., 3:00 p.m. and shortly before the polls close. . . . After the polls close, the network analysts also begin to look at estimates based on larger samples of approximately 2,000 randomly selected precincts where NEP personnel obtain official vote tallies as they become available. The networks typically use this larger system of tabulations and estimates — rather than the exit polls alone — to call close contests after the polls close. But when the vote is really close, as it is likely to be tonight in states like Missouri and Virginia, even the larger samples of hard returns will be inadequate. The analysts will have to watch the complete vote count, just like the rest of us. In years past, hundreds of producers, editors and reporters would have access to the mid-day estimates starting at about noon, and preliminary exit poll cross-tabulations (like this one) would inevitably leak out. This year the networks have taken steps to prevent such leaks, creating a "Quarantine Room" where, as the Washington Post's Howard Kurtz reports, "two people from each of the networks and the Associated Press" will be allowed "entree to a windowless room in New York [where] all cellphones, laptops and BlackBerrys will be confiscated. The designated staffers will pore over the exit polls but will not be allowed to communicate with their offices until 5 p.m." So there you have it folks. At 5:00 p.m. the data will be flowing to newsrooms as it always does and the usual leaks will presumably commence shortly thereafter. One rationale for the delay is that the data available at that hour will be more representative and not just based on those who vote in the morning. So if this process is so sophisticated and the late afternoon numbers are better, why can't we rely on the leaked "numbers" that will undoubtedly leak after 5:00 p.m. today? 1) It is still just a survey . . . . 2) Early or absentee voting . . . . 3) Past Errors favored Democrats . . . . 4) Limited Data on the House elections . . . . Expect heavy hinting by the networks after 5pm ET today.