I need to do the proof for the second condition but I'm not getting the right answer.
} is a martingale if
1) E[| |]<
2) E[ ] =
Suppose E[| |] < and E[ ]=1
Prove that } is a martingale
I can prove the first condition but for the second one I keep getting E[ ] = which is wrong. Can anyone shine a light on this problem? Thanks
(ps sorry for any bad use of LaTex, this is the first time I have used it!)