CarnalK
November 17, 2016, 4:02am
11
I addressed the supposed “math” in an earlier thread:
http://boards.straightdope.com/sdmb/showthread.php?t=811092
From the linked article:
Exit polls have a much larger intrinsic margin for error than regular polls. This is because of what are known as cluster sampling techniques. Exit polls are not conducted at all precincts, but only at some fraction thereof.
[…]
Exit polls have consistently overstated the Democratic share of the vote. Many of you will recall this happening in 2004, when leaked exit polls suggested that John Kerry would have a much better day than he actually had. But this phenomenon was hardly unique to 2004. In 2000, for instance, exit polls had Al Gore winning states like Alabama and Georgia (!).
Exit polls may have problems calibrating results from early voting. Contrary to the conventional wisdom, exit polls will attempt account for people who voted before election day in most (although not all) states by means of a random telephone sample of such voters. However, this requires the polling firms to guess at the ratio of early voters to regular ones, and sometimes they do not guess correctly.
Saying “exit polls are historically much more accurate” than pre-election polls doesn’t seem to have any basis in reality. One might even describe that line as “a pile of bullshit” but I’m perfectly happy to be proven wrong by a cite that doesn’t require me to watch a video.