Let 0<q<1 suppose that
T=qx +(1-q)Y  and  Z=I*X+(1-I)Y
Where I~Bernoulli(q) (takes value 1 with probability q and 0 with prbability 1-q)
Comapre E[T^k] and E[Z^k] for k=1, 2

谢谢了