文档介绍：填空题
(1) If P(AB)=0, then =
(2) Suppose , then E(3X2-6)=
(3) A sample X1,X2,…,Xn drawn from population , and , then , .
(4)Suppose===,=,=0,=.then =
(5)The area under the standard normal curve between 0 and is
(6) A sampledrawn from population.
, then ,
(7) The correlation coefficient of X and Y is defined by=
(8) If, then the moment estimator of parameter p is
(9) If P(A)=.8, P(AB)=.4, then =
(10)The area under the standard normal curve between - and 0 is
(11) A sampledrawn from population.
, then ,
(12) The correlation coefficient of X and Y is defined by=
(13)Suppose ===,=,=0,=.
then =
(14) A sample drawn from population.
, then ,
(15)设A,B互斥,已知P(A)=α,P(B)=β,则
(16)设随机变量X的密度函为,则a=
(17)设DX=4,DY=9,ρXY=,则D(2X-3Y)=
(18)设随机变量X数学期望EX=μ,方差DX=σ2,则由切比雪夫不等式
P{|X-μ|2σ}
(19)设X1,X2,…X10为来自正态总体N(μ,σ2)的一个样本,为这样本的样本均值,则随机变量
~
(20)设总体X~P(λ)(泊松分布),则=
(21)已知总体X~N(μ1,),Y~N(μ2,),(X1,…,Xm)是来自X的样本,其样本修正方差为,()是来自Y的样本,其样本修正方差为。当μ1,μ2未知时,对假设H0,,H1:>进行检验,这时构造的统计量为,其拒绝域为
选择题
(1) If X, Y are independent random variables, and ,then ( )
a. X=Y b. P(X=Y)=1 c. P(X=Y)= d. P(X=Y)=0
(2) For a discrete random variable X, and EX=1,Var(X)=3, then ( )
a. b.
c. d.
(3) If , then ( )
a. b. c. d.
(4) If , X1, X2, X3 are , and is a sample from population X, then the best estimators of μis ( )
a. X1 b. c. d.
(5) Let X be a random variable with