Higher or lower on a d100 paid the second value
Question
A fair die with faces to is rolled and you see the result . You then predict whether a second roll will be at least ("higher") or strictly below ("lower"). If your prediction is right you are paid dollars, otherwise nothing. Playing to maximise expected payout, what is the smallest first roll for which you should predict "lower"?
Short answer
. Predicting lower pays on average, while predicting higher pays . Lower wins when , which first happens at (the crossover is near ): at , , while at , .
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