设总体,是来自总体X的样本，则的矩估计量为（ ）/ananas/latex/p/474646/ananas/latex/p/84069/ananas/latex/p/479

A .https://assets.asklib.com/images/image2/2017073016533931075.jpg B .https://assets.asklib.com/images/image2/2017073016534650114.jpg C .https://assets.asklib.com/images/image2/2017073016535238292.jpg

A . X B . S2 C . S D . 2

A．1/5 B．2/5 C．3/5 D．4/5

<img src='https://img2.soutiyun.com/ask/2020-11-24/975077556161539.jpg' />

设<img src='https://img2.soutiyun.com/ask/2020-11-18/974564391566801.png' />是来自总体X的简单随机样本，已知X~E(λ),其中λ＞0是未知参数,试求 (I)λ的矩估计量<img src='https://img2.soutiyun.com/ask/2020-11-18/974564415083146.png' /> (II)λ的最大似然估计量<img src='https://img2.soutiyun.com/ask/2020-11-18/974564423164609.png' />

设总体X服从均匀分布<img src='https://img2.soutiyun.com/ask/2020-07-30/964966697678453.png' />取容量为6的样本值: <img src='https://img2.soutiyun.com/ask/2020-07-30/964966707200997.png' /> 则θ的矩估计为(); 最大似然估计为

A．<img src='https://img2.soutiyun.com/latex/latex.action' /> B．<img src='https://img2.soutiyun.com/latex/latex.action' /> C．<img src='https://img2.soutiyun.com/latex/latex.action' /> D．<img src='https://img2.soutiyun.com/latex/latex.action' />

<img src='https://img2.soutiyun.com/ask/2020-08-04/965404827120282.png' />

设总体X服从[-θ,θ]上的均匀分布,其中θ(θ>0)为未知参数，<img src='https://img2.soutiyun.com/ask/2020-07-27/964695089964574.png' />是来自总体的简单随机样本. (1)求θ的矩估计量<img src='https://img2.soutiyun.com/ask/2020-07-27/964695055661612.png' />;(2)求θ的最大似然估计量<img src='https://img2.soutiyun.com/ask/2020-07-27/964695070951486.png' />.

设<img src='https://img2.soutiyun.com/ask/2020-10-04/970677075262129.png' />是取白总体X的一个样本，总体X的密度函数为<img src='https://img2.soutiyun.com/ask/2020-10-04/970677090889023.png' /> 求a的矩估计量.

<img src='https://img2.soutiyun.com/ask/2020-07-30/964967903391416.png' />

设总体X~U<0.θ).其中未知参数θ>0。<img src='https://img2.soutiyun.com/ask/2020-07-27/964695041852822.png' />为来自总体X的一个简单随机样本,求θ的矩估计量<img src='https://img2.soutiyun.com/ask/2020-07-27/964695055661612.png' />和最大似然估计量<img src='https://img2.soutiyun.com/ask/2020-07-27/964695070951486.png' />.

设<img src='https://img2.soutiyun.com/ask/2020-11-18/974563944699242.png' />是来自区间[-a,a].上均匀分布的总体X的简单随机样本，则参数a的矩估计量<img src='https://img2.soutiyun.com/ask/2020-11-18/974563958950057.png' />=____.

B、θ的极大似然估计值是0.7 C、θ的矩估计值是0.6 D、θ的极大似然估计值是0.5 E、θ的矩估计值是0 F、θ的极大似然估计值是0.6

设总体X的一个样本为(X₁,X₂,...,X_n),X的分布密度为 <img src='https://img2.soutiyun.com/ask/2020-10-06/970839014948484.jpg' /> 参数θ＞0未知.(1)求0的矩估计量;(2)求矩估计量的方差;(3)求0的最大似然估计量.