It recommended the use of probability sampling at all levels of respondent selection, and the elimination of quotas. There was, of course, another reason for this most famous of polling mistakes ...

If you have a true probability sample from a perfect sampling frame, with 100 percent availability and 100 percent response, and if your sampling probabilities don’t vary much, and if your data ...

The sampling frame is the listing of sample units, derived from the universe, from which the sample is selected. However, in some cases, ...

Defining the Universe, the Sampling Unit, and the Sampling Frame. The revised PIM puts a finer point on the identification of the claims universe. Specifically, “[t] ...

Sampling and data collection for most of these polls is conducted by TNS Intersearch of Horsham, Pa. TNSI and its predecessor, Chilton Research Services, have been ABC News' primary fieldwork ...