Ok if anyone is reading this old thread I'd love some clarification. In thislink above from JohnM I am getting lost at the step underlined in red in the attached image. Very similarly, I get lost following this thread when someone provides the explanation that "We know in general that Var(kY)=k^2Var(Y)". Sorry, but I don't know that, in general Can anyone explain why there is all of a sudden a squared (1/n) term in the math? i.e. can you elaborate on why "Var(kY)=k^2Var(Y)" and not"Var(kY)=kVar(Y)"?
Hi Dason, thanks. I've attached something that I think makes sense and explains the answer to my question, but I don't have formal training in this and am not certain. Can you take a look? Where can I read and intro to the "properties of the expectation operator".