Decreased Sample size.

• With 100 coin tosses (a polling sample of 100), the statistical error is 5% -- too big to be comfortable. There is a simple rule for such errors

  • If you want to halve error, you must quadruple the sample size. Thus with 400 coin tosses the error is 2.5% which is half the result for 100 coin tosses.

100 Coin Tosses

400 Coin Tosses

Error 5%

Error 2.5%

Shape is still aGaussian

1000 Coin Toss Errora factor of Sqrt(10)Smaller than 100 Tosses

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