問題詳情

十六. Consider the famous hat problem as in the previous problem. Let X, be a random variablethat takes value 1 if the ith person selects his/her own hat, and takes value O otherwise. Letcov(Y, Z) = [Y . Z] -E[Y] ㆍE[Z] be the covariance of two random variables Y and 2. Whichof the following statements is/are true?
(A) When n = 4, cov(X4, X4) is

.
(B)When n = 4,cov(X1,X2)=


(C) When n = 4, va

=2.
(D) When n = 4, Xi and Xz are statistically independent.
(E) For any two random variables Y and Z, cov(Y, Z) ≥0.

參考答案

答案：[無官方正解]
難度：計算中-1
書單：沒有書單，新增