[SE Mom]

None known.

Speaking of strange polls- as Greta is talking about now- check this out:

http://www.realclearpolitics.com/horseraceblog/2008/10/more_on_the_polls_1.html

Pew is not the only poll behaving in this fashion. Today, the Gallup traditional model pegs McCain’s number significantly higher than the RCP average. It has done this several times over the last three weeks - and every day since it began it has shown McCain doing better than the RCP average. It is unlikely that random variation would produce these effects. Today’s Rasmussen poll shows McCain significantly higher than the RCP average, and it has consistently been higher than the RCP average for the last three weeks. IBD/TIPP frequently pegs Obama’s number significantly lower than the RCP average, and it has shown him lower than the RCP average every day since it began. The GWU/Battleground poll has shown McCain consistently higher than the RCP average for 10 of the last 10 release dates, frequently at significant levels.

None of this is consistent with what we would expect from random statistical variation. These considerations reinforce the point I made on Friday. In all likelihood, something else is going on here. The pollsters have different “visions” of what the electorate is, and these visions are inducing such divergent results.

This is why I would urge caution when interpreting all this polling data. We’re talking about disagreements among good pollsters. I take all of these firms seriously whenever they produce new numbers. They are disagreeing with one another in ways that can’t be chalked up to statistical “noise.” That gives me great pause.

[Right Wing Assault]

In all likelihood, something else is going on here.

It's called cooking the books. Or, in simpler terms, lying.

[muawiyah]

These are not disagreements among "good pollsters". Some of the pollsters are absolutely abominable and they know it.

If Bill Clinton hadn't killed off the call center business in the United States (in the dot.com bust) the pollsters would still have had access to professional telephone workers who could do proper screening of those being sampled by the pollsters.

Presently most of the pollsters have to rely on college kids taking part time seasonal work and doing the calling from less than ideal situations (rooms, not studios, no supervisors, etc.).

I don't believe it's possible to get valid data anymore.