Friday, April 01, 2005

Analysis of 2004 US Election Exit Polls

I couldn't let this one slide on by without comment. That shady quadrennial event called the US election seems to be at odds with the exit polling results. I've written about it before for the Gateway.

Several methods have been used to estimate the probability that the national exit poll results would be as different as they were from the national popular vote by random chance. These estimates range from 1 in 959,000 to 1 in 1,240.3 No matter how one calculates it, the discrepancy cannot be attributed to chance.

The report states that:

There are Three Primary Explanations for the Discrepancies:

1. Statistical Sampling Error – or Chance
We agree with Edison/Mitofsky that the first possible cause, random statistical sampling error, can be ruled out.

2. Inaccurate Exit Polls
This is the theory that Edison/Mitofsky put forth. They hypothesize that the reason the exit polls were so biased towards Kerry was because Bush voters were more reluctant to respond to exit polls than Kerry voters. Edison/Mitofsky did not come close to justifying this position, however, even though they have access to the raw, unadjusted, precinct-specific data set. The data that Edison/Mitofsky did offer in their report show how implausible this theory is.

3. Inaccurate Election Results
Edison/Mitofsky did not even consider this hypothesis, and thus made no effort to contradict it. Some of Edison/Mitofsky's exit poll data may be construed as affirmative evidence for inaccurate election results. We conclude that the hypothesis that the voters’ intent was not accurately recorded or counted cannot be ruled out and needs further investigation.