Before revision: If B is a mean-preserving spread of A, then B has a higher variance than A ; but the converse is not in general true, because the variance is a complete ordering while ordering by mean-preserving spreads is only partial.
After revision: and the expected value of A and B are identicalIf B is a mean-preserving spread of A, then B has a higher variance than A ; but the converse is not in general true, because the variance is a complete ordering while ordering by mean-preserving spreads is only partial.