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P-Values: The Infamous Coin Toss
Defined.
The p-value is a number. It tells you how likely something were to be true, given nothing "special" is going on.
Example.
That definition was pretty vague, so here's an example claim: "I can always flip a coin and get heads." After flipping 10 times, the coin lands on heads 8 times.
Analysis.
In our coin-flipping example, the p-value (~0.03) would represent the chance you'd get 8 or more heads purely out of luck. This small value implies that this outcome is pretty unlikely to happen by chance, so the coin toss might be unfair.
Ramifications.
In actuality, the toss indeed wasn't fair-the coin was marginally heavier on one side causing the final outcome to result in heads more frequently. Thus, the p-value served as a valuable metric explaining why the outcome was biased.
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