320.Which Die Am I Holding
★★★conditional probabilityIMC Trading
There are two dice, one numbered 1 to 6 and the other numbered 1 to 4. One is chosen at random and rolled twice. The first roll shows a 2. What is the expected value of the second roll?
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The first roll is evidence about which die you are holding. Update, then average the two dice's means with the posterior weights.
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