Statistics

I know how to do these questions, I was just wondering that I might have mixed some stuff up here:

The expected value of the statistic we are trying to find in part (a) is E(X1 + X2 + X3 + X4) = E(X1) + E(X2) + E(X3) + E(X4) = 4E(X).

The expected value of X-bar, is E(X) by definition since they are assumed to be independent and identically distributed random variables in a sample. So, is it correct to say E(X-bar) = 0.2 and E(sum in part(a)) = 0.8 because E(X) = 0.2 because the probability parameter is = 0.2 which is also the expected value of the random variable!

Thank you!

(edited 4 years ago)

Reply 1

ghostwalker

Original post by Chittesh14

I know how to do these questions, I was just wondering that I might have mixed some stuff up here:

Just to be clear - the given question has nothing to do with expectation.

The expected value of the statistic we are trying to find in part (a) is E(X1 + X2 + X3 + X4) = E(X1) + E(X2) + E(X3) + E(X4) = 4E(X).

Yes.

The expected value of X-bar, is E(X) by definition since they are assumed to be independent and identically distributed random variables in a sample. So, is it correct to say E(X-bar) = 0.2 and E(sum in part(a)) = 0.8 because E(X) = 0.2 because the probability parameter is = 0.2 which is also the expected value of the random variable!

Thank you!

Yes, though I'm not clear which "random variable" you're refering to at the end and how it differs, if at all, from what you've said already.

Reply 2

Chittesh14

Original post by ghostwalker

Just to be clear - the given question has nothing to do with expectation.

Yes.

Yes, though I'm not clear which "random variable" you're refering to at the end and how it differs, if at all, from what you've said already.