Sizu Riatto
Statistics Didn’t Have to Be This Hard · Chapter 12

Is It Just Luck?

Sixty heads in a hundred flips. Twenty-five sixes in a hundred rolls. How often would pure luck do that? Enter the counts and the chance if nothing were going on, and get the exact answer.

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Enter the counts, then press Calculate.
From the book, Chapter 12. The p-value is the chance of a result at least this extreme if only luck were at work. Sixty or more heads from a fair coin: 2.8% one-sided, 5.7% two-sided. Decide the direction before you look at the data. A small p-value is evidence, not proof; a large one means “not proven”, not “no effect”.

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