[PJ-Comix]

Does it skew the poll or just take them out of the sample?

When you take a group out of a sample it definitely skews a poll.

[deport]

But how do you know they are out of the sample? Of a 1000 sample how many do you think will not answere just because they have ID? The sample taken still is representative of the populace surveyed. The real question is is that populace representative of the whole populace? Just because you don't answer doesn't mean you have a different opinion than someone who took you place on the call list..... or does it?