Statistics and Probability Dictionary
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Statisticians use a confidence interval to express the degree of
uncertainty associated with a sample
A confidence interval is an
combined with a probability statement.
For example, suppose a statistician conducted a survey and computed an interval
estimate, based on survey data. The statistician might use a
to describe uncertainty associated with the interval estimate.
He/she might describe the interval estimate as a "95% confidence interval".
This means that if we used the same sampling method to select different samples and
computed an interval estimate for each sample,
we would expect the true population parameter to fall within the interval estimates
95% of the time.
Confidence intervals are preferred to
and to interval estimates, because only confidence
intervals indicate (a) the precision of the estimate and (b) the uncertainty of