>>I think that in order for the Confidence level Calc to be reliable, you have to assume the sample was completely random. IOW, if the sample was skewed, i.e. just call households in Scarsdale, NY, that would definitely skew the results.
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>Just call at random and you get a random sample of those who still keep landlines. I know a few people who never bothered to get one, cell phone is their only phone. So these are out.
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>Next, there are people who never answer any surveys, who have their land line cut off (because they're unemployed and aren't paying their phone bill), those hiding from the law, those whose last phone line was in their repo'd home,... and you end up with a very random sample of people who aren't in any of these categories.

Most of the questions raised on this thread regarding these statistics and the way they are compiled are answered if anyone bothered to read the original link : http://www.bls.gov/cps/cps_htgm.htm#where
See: "Where do the statistics come from" and "Who is counted as employed/unemployed"
And, yes, some in the sample are interviewed by phone - but they are *not* in the sample because they have a phone......