Statistics · Statistical sampling
Chapter 1 · 3
The idea
Sampling distributions of a statistic
A statistic such as the total, mean, median or range of a sample changes from sample to sample, so it has a probability distribution of its own: list the samples, price each one, collect them by the value of the statistic, then use the table for probabilities, expected values and the smallest number of samples that makes an outcome likely.
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Statistics · Statistical sampling
Sampling distributions of a statistic
A statistic such as the total, mean, median or range of a sample changes from sample to sample, so it has a probability distribution of its own: list the samples, price each one, collect them by the value of the statistic, then use the table for probabilities, expected values and the smallest number of samples that makes an outcome likely.
Why it works
Different samples, different answers
At a school fair, a lucky-dip barrel holds thousands of tokens. Three in every four are worth point and the rest are worth points. You take three tokens and your prize depends on your total. Asha draws and scores . Ben draws and scores .Nobody knows your total until you draw, so it is a random variable, . This page answers one question: before anyone draws, which totals are possible, and how likely is each? That list is the sampling distribution of .
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