In just about any discussion of a poll about the very close presidential race between Vice President Kamala Harris and former President Donald Trump, you’ll hear ...

Wondering how many people in the United States have a smartphone? If you poll 20 people on the street, your survey won’t be representative of the entire American population. But if you just want to ...

Oct. 8, 2008— -- Surveys based on a random sample of respondents are subject to sampling error – a calculation of how closely the results reflect the attitudes ...

If a tax impact study, derived from observations on income tax returns, is to provide tax estimates with the same margin of error and significance level for each ...

In presidential elections, even the smallest changes in horse-race poll results seem to become imbued with deep meaning. But they are often overstated. Pollsters ...

Andrew Gelman, a professor in the departments of statistics and political science at Columbia University, explains. A "3 percent margin of error" means that there is a 95 percent chance that the ...