Learn how representative samples and random samples differ and why combining them minimizes sampling bias for accurate data.
Discover how to determine the ideal percentage of a population for a representative sample to ensure accurate data analysis with minimal sampling error.
Note: This report was updated on Dec. 30, 2015 to reflect the January-July 2015 National Health Interview Survey estimates released on December 1, 2015. Telephone surveys face numerous challenges, but ...
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