(13)(2010年,一)设总体X的分布为:-|||-X 1 2 3-|||-p https:/img.zuoyebang.cc/zyb_2a76612f05065171cccaed4e98b26d93.jpg-theta theta -(theta )^2 θ^2-|||-其中 theta in (0,1) 未知,以N1表示来自总体X的简单随机样本(容量为n)中等于i的-|||-个数 (i=1,2,3) ,试求常数a1,a2 ,a3使 =sum _(i=1)^3(a)_(i)(N)_(i), 为θ的无偏估计量,并求T-|||-的方差.

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

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

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

三、解答与证明题-|||-1.设总体X具有分布律:-|||-X 1 2 3-|||-p θ θ .https:/img.zuoyebang.cc/zyb_dfb

X 1 2 3-|||-p .-1 .https:/img.zuoyebang.cc/zyb_9e778ee622bfcbd85bc2aaa7e97331dd.

设矩阵A= (3,-2) ,B= 2 4 https:/img.zuoyebang.cc/zyb_7142fe6d884b795b75323081826723e

[题目]-|||-设 =x+-|||-A 1/2-|||-B 2-|||-C e-|||-D https:/img.zuoyebang.cc/zyb_e34c8

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

设线性方程组_(1)+(x)_(2)+(x)_(3)=0-|||-x https:/img.zuoyebang.cc/zyb_11f7ffe17b3d923f0

2.单选题-|||-设 backsim N(1,4), ϕ(x) 为标准正态分布的分布函数,则-|||-P lt xlt 2 __-|||-A https:/i