Page 196 - Statistics for Dummies

In this part . . .
nytime you’re given a statistic by itself, you haven’t
Areally gotten the full story. The statistic alone is
missing the most important part: by how much that statis-
tic is expected to vary. All good estimates of population
parameters contain not just a statistic but also a margin of
error. This combination of a statistic plus or minus a mar-
gin of error is called a confidence interval.
Now suppose you’re already given a claim, assumption, or
target value for the population parameter, and you want
to test that claim. You do it with a hypothesis test based
on sample statistics. Because sample statistics will vary,
you need techniques that take this into account.
This part gives you a general, intuitive look at margin of
error, confidence intervals, and hypothesis tests: their
function, formulas, calculations, influential factors, and
interpretation. You also get quick references and exam-
ples for the most commonly used confidence intervals
and hypothesis tests.

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