This survey was conducted by
Harris Interactive by telephone within the United States between June 16
and 19, 2006 among a nationwide cross section of 1,007 adults (aged 18 and
over). Figures for age, sex, race, and region were weighted where
necessary to bring them into line with their actual proportions in the
In theory, with probability samples of this size, one could say with 95 percent certainty that the results for the overall sample have a sampling error of plus or minus 3 percentage points. Unfortunately, there are several other possible sources of error in all polls or surveys that are probably more serious than theoretical calculations of sampling error. They include refusals to be interviewed (e.g., non-response), question wording and question order, and weighting. It is impossible to quantify the errors that may result from these factors.