1. Mean and Variance

Hi everybody,

I encountered this to me very confusing problem in the context of confidence intervals and pivotal quantities.

How can I compute the mean and the variance (marked yellow) with this information below...

Many thanks once more!

2. Re: Mean and Variance

Hello,

The only random stuff in $\hat\theta_2$ is $x_i$. So if you treat everything else as a constant, it's pretty easy to compute the mean and the variance !
After that, it's just a matter of computing double sums

Let's try it !

3. Re: Mean and Variance

Thanks, I think I found out now!