Ahem, the probability and statistics exam is coming, so hurry up and review. This course is not easy (I'm sweating like a pig before I review it)

Haha, I can do this problem now.

Firstly, the expectation of X-band @ (instead of sei tower) is calculated by probability density formula: the result is (2@+ 1)/4, that is, u=(2@+ 1)/4.

If 4X (pull) 2 is an unbiased estimate of @ 2, then there is En(4X (pull) 2) = @ 2. Because en (4x (pull) 2) = en (4x (pull)) 2 = 4 * u 2 = (2 @+1) 2/4 is not equal to @ 2, it is not an unbiased estimation of @ 2.