Logic / Unit 7 Logic 333 short lesson, about 20 seconds
Sample Size and Sample Bias
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The idea
Samples fail small — too few cases — or crooked: systematically unrepresentative. Bias is worse; no sample size cures it.
In practice
The 1936 Literary Digest poll: 2.4 million responses, a skewed sampling frame, and heavy nonresponse bias. Landslide predicted; landslide happened — the other way.
Where people slip
Big and biased beats small and biased only at being confidently wrong.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Builds on
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