Survey facts & stats

Question 1

For a poll of about 1,000 people, what margin of error does that sample size typically produce?

Accepted Answer

about +/-3%. A sample of 1,000 respondents typically yields a margin of error around 3 percentage points at a 95% confidence level.

Question 2

To shrink a poll's margin of error down to about plus/minus 1%, roughly how many respondents are needed?

Accepted Answer

about 10,000. Cutting the margin of error to around 1% requires a sample roughly ten times larger than a typical 1,000-person poll.

Question 3

In the famous 1948 U.S. election polling failure, which candidate did polls wrongly predict would win?

Accepted Answer

Thomas Dewey. Polls confidently predicted a Dewey win, but Harry Truman won instead - one of the most famous polling errors in history.

Question 4

In 1938, Jean Stoetzel founded IFOP, described as the first survey institute of its kind, in which country?

Accepted Answer

France. IFOP, founded in Paris in 1938, is considered the first European survey research institute.

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