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A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaProbability or paradox

This theorem updates a probability using prior beliefs and new evidence.

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Math & LogicOne small aha
Your new ahaBayes' Theorem

Bayes' Theorem: Updates the probability of an event as new evidence arrives. Source: Bayes' theorem ↗

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More from Chance & Paradoxes

A few more worth knowing.

  1. 08In this three-door game-show puzzle, switching wins with probability 2/3 when an informed host always reveals a goat and offers a switch.RECALL
    The Monty Hall Problem

    The Monty Hall problem shows that switching doors, though counterintuitive, actually improves your odds of winning.

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  2. 09This birthday-sharing puzzle reaches just over a 50% match probability with 23 people under the usual equal-day assumptions.RECALL
    The Birthday Paradox

    The birthday paradox shows that just 23 people give roughly even odds that two share a birthday.

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  3. 10In this statistical paradox, a trend in separate groups reverses when the groups are combined.RECALL
    Simpson's Paradox

    Simpson's paradox shows a data trend can reverse once separate groups are combined, a caution for statistics.

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