X 1 2 3-|||-p .-1 .https:/img.zuoyebang.cc/zyb_9e778ee622bfcbd85bc2aaa7e97331dd.jpg-theta .https:/img.zuoyebang.cc/zyb_9e778ee622bfcbd85bc2aaa7e97331dd.jpg-20-|||-其中θ未知,现取得一组样本值:1,1,1,3,2,1,3,2,则θ的矩估计值为-|||-__-|||-(A) dfrac (31+sqrt {97)}(48)-|||-B ) dfrac (9)(20)-|||-(C) dfrac (31+sqrt {97)}(48) 或 dfrac (31-sqrt {97)}(48)-|||-(D) dfrac (31-sqrt {97)}(48)

设总体X的概率分布为X 0 1 2-|||-P (theta )^2 https:/img.zuoyebang.cc/zyb_9a4dc435e7d9078a6

.https:/img.zuoyebang.cc/zyb_39fb1dd0e2e3f867277e49a796f675bc.jpg-9 试画出图示各构件的受力图

2.设总体X的分布律为-|||-X 0 1 2 3-|||-p θ^2 (1-theta ) θ^2 https:/img.zuoyebang.cc/zyb_a

(2)已知 P(A)=1/2 (B)=1/3 (C)=1/5, P(AB)=1/10 (AC)=1/15 (BC)=-|||-https:/img.zuoyeb

*(CO)=0.678 . https:/img.zuoyebang.cc/zyb_d7bd9e4c4e6bf8bf7c5501cba60ee7e8.jpg(x

. https:/img.zuoyebang.cc/zyb_59b3de1062e243c0b1e32e8058920d73.jpg+({x)_(n)}^2

6.总体X的概率分布为-|||-x 0 1 2 3-|||-P θ^2 (1-0) θ^2 https:/img.zuoyebang.cc/zyb_d23f4d

(13)(2010年,一)设总体X的分布为:-|||-X 1 2 3-|||-p https:/img.zuoyebang.cc/zyb_2a76612f050

平面https:/img.zuoyebang.cc/zyb_443e7b4f4bf9228e9f1fec85132a95c9.jpg:2x+3y+4z+1=0

https:/img.zuoyebang.cc/zyb_e8bd054ef3dd65e8f324cadbf8b2d8a0.jpg-beta , 且β已知 E.