Minimum sample size = 30 and the 10% rule for independence of trials

Agent Smith

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Oct 18, 2023
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Desmos graph

In the graph above, y\displaystyle y = Sample size and p\displaystyle p = population size.

1. The 10% rule for ensuring the independence of trials
y0.1p\displaystyle y \leq 0.1p. Required for accuracy of the standard deviation (?)

2. The minimum sample size = 30\displaystyle 30 so that we can have a normal sampling distribution
y30\displaystyle y \geq 30. Required to ensure the sampling distribution is a normal distribution)

So ...

0.1p30    p300\displaystyle 0.1p \geq 30 \implies p \geq 300

To satisfy both conditions (which as far as I can tell is required in sampling distributions), the minimum size of the population p300\displaystyle p \geq 300.

Am I supposed to interpret this as statistical questions are meaningless for populations < 300? That is to say to do statistics we need a population of at least 300?
 
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