对于总体的被估计指标X，找出样本的两个估计量x1和x2，使X落在区间（x1，x2）内的概率为已知。这就是区间估计。

A .https://assets.asklib.com/psource/2015102915530155953.jpg B .https://assets.asklib.com/psource/2015102915531942539.jpg C .https://assets.asklib.com/psource/2015102915532911179.jpg D .https://assets.asklib.com/psource/2015102915534171578.jpg

A .https://assets.asklib.com/psource/2015102915515648810.jpg B .https://assets.asklib.com/psource/2015102915521272593.jpg C .https://assets.asklib.com/psource/201510291552233937.jpg D .https://assets.asklib.com/psource/2015102915523584859.jpg

A . ['['https://assets.asklib.com/psource/2015102914501741849.jpg B .https://assets.asklib.com/psource/2015102914503351857.jpg C .https://assets.asklib.com/psource/2015102914504519297.jpg D . X1

A . ['x5B .https://assets.asklib.com/psource/2015103009361331257.jpg C . nD .https://assets.asklib.com/psource/2015103009362870429.jpg

A .https://assets.asklib.com/psource/2015102914494644051.jpg B . S2C . 0.4X1+0.6XD . -X1

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

<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<img src='https://img2.soutiyun.com/ask/2020-10-04/970677629200813.png' />是取自总体X的一个样本，X的分布函数为<img src='https://img2.soutiyun.com/ask/2020-10-04/970677646302791.png' />，其中θ未知，θ＞0.试求θ的极大似然估计量.

A．<img src='https://img2.soutiyun.com/ask/uploadfile/5730001-5733000/083bcb3c0123c977d3b9f837f23eeaff.jpg' />B．<img src='https://img2.soutiyun.com/ask/uploadfile/5730001-5733000/fd1704f3fa44fefc4b940c8641ecdba5.jpg' />C．<img src='https://img2.soutiyun.com/ask/uploadfile/5730001-5733000/8e37ad5b6e73b883501a81bf5c8b7d1e.jpg' />D．<img src='https://img2.soutiyun.com/ask/uploadfile/5730001-5733000/918c0dfbd770405c7b4389607fde7feb.jpg' />E．以上均不正确

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.

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' />.

<img src='https://img2.soutiyun.com/ask/2020-08-04/965403794587224.png' />

设<img src='https://img2.soutiyun.com/ask/2020-10-04/97067783598264.png' />是取自总体X的一个样本，总体X的密度两数为<img src='https://img2.soutiyun.com/ask/2020-10-04/970677902197427.png' />，其中-∞＜μ＜+∞，μ未知，易知μ的极大似然估计量，问： (1)<img src='https://img2.soutiyun.com/ask/2020-10-04/970677922640596.png' />是μ的无偏估计吗？若不是，请修正. (2)μ的矩估计量<img src='https://img2.soutiyun.com/ask/2020-10-04/970677942041706.png' />是μ的无偏估计吗？是相合估计吗？

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' />=____.

设总体X有数学期望μ=E(X)，(x.x,)为样本，则下列哪个估计量是μ的无偏估计量()。 <img src='https://img2.soutiyun.com/ask/2020-09-10/968583547233787.png' />