As Americans await election results, many are looking to the polls for clues. From the margins of error to methodology, here’s what to know about presidential polls.

As Americans await election results, many are looking to the polls for clues. From the margins of error to methodology, here’s what to know about presidential polls.

Sampling error, however, is oversimplified when presented as a single number in reports that may include subgroups, poll-to-poll changes, lopsided margins and results measured on the difference.

You can’t get into an argument about polls without some wise guy whipping out the “margin of error” to shut down the other side. But what is the margin of error, exactly?

Detailed information on Pew Research Center international survey meethodology, such as mode of interview, sampling design, margin of error, and design effect, for each country we survey, organized by ...