Variance of bootstrap sample of size n

AI Thread Summary
The discussion focuses on calculating the bias of the bootstrap sample variance estimator, specifically \(\hat{\theta^*}\). The user initially finds the bias to be \(\frac{\theta}{n}\) but struggles to proceed with the calculations. There is confusion regarding whether the results in their notes pertain to the sample mean or the population variance, as the question specifically asks for the bias in \(\hat{\theta^*}\). The user attempts to manipulate the expression for bias but encounters difficulties when taking expectations. The conversation highlights the complexities of understanding bias in different statistical estimators.
ghostyc
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http://img138.imageshack.us/img138/6060/98259799.jpg

I have done part one and found that the bias is \frac{\theta}{n}

then i don't know how to proceed.

in my notes, have the following result,

http://img189.imageshack.us/img189/9699/resultc.jpg

i am thinking, this time i have to find the bias in \hat{\theta^*}
then, if i work through, i got it's unbiased...

am i doing something wrong?

I am confused with that, the result in my notes, is it for the mean of the sample?

but here, we are aksed for the population variance?

Thanks
 
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(ii) is asking about theta star HAT, not theta star BAR.
 
EnumaElish said:
(ii) is asking about theta star HAT, not theta star BAR.

i will look into it again
sometimes, i really get confused what i am looking for
 
EnumaElish said:
(ii) is asking about theta star HAT, not theta star BAR.

I am now working on the bias is

<br /> \bar{\theta}^{*} - \hat{\theta} = \frac{1}{n} \sum_{i=1}^n (y_i^* - \bar{y} )^2 - \frac{1}{n} \sum_{i=1}^n (y_i - \bar{y} )^2<br />
after some munipulation , i got to

<br /> <br /> \frac{1}{n} \sum_{i=1}^n \left( {y_i^*}^2 - y_i^2 -2\bar{y} (y_i^*+y_i) \right)<br /> <br />

then i take expectation, i got stuck again...
 
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