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Conditioned on the result of an unbiased coin flip, the random variables T1 , T2, . . . , T7, are independent and identically distributed, each drawn from a common normal distribution with mean zero. If the result of the coin flip is Heads, this normal distribution has variance 1; otherwise, it has variance 4. Based on the observed values 1,132, . . . ,tn, we use the MAP rule to decide whether the normal distribution from which they were drawn has variance 1 or variance 4. The MAP rule decides that the underlying normal distribution has variance 1 if and only if n 71 Cl 21534-62 Zti