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A/B testing 0:39
A 39-second explainer of A/B testing, narrated over the same demo you can try yourself.
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What this video covers
A/B testing shows two versions of something to two random groups and compares a metric - clicks, sign-ups, sales - to see which performs better. Done right it settles design arguments with evidence; done hastily it manufactures false winners from noise.
Early on, one version looked like a clear winner - and if you'd called it then, you'd have shipped a difference that was pure chance. Pour in more visitors and the gap melts into the noise, because the two were really the same all along. That gap between an early lead and a real result is the whole discipline of A/B testing.
