Paulos explains Freeman's work on the exit poll stats rather well. He begins -
"Why did the exit polls taken on election day in the battleground states differ so starkly from the final tallies in those states? As my crosstown colleague, Steven Freeman of the University of Pennsylvania has demonstrated in his paper, "The Unexplained Exit Poll Discrepancy," the pattern is unmistakable. In Ohio, Pennsylvania, and Florida, the differences between Bush's final tallies and his earlier exit poll percentages were, respectively, 6.7%, 6.5%, and 4.9%."
Here's the link to the rest of the article: Paulos on the Exit Polls