问题如下：
Suppose the payoff from a merger arbitrage operation is $5 million if successful, —$20 million if not. The probability of success is 83%. The expected payoff on the operation is
选项：
A.$5 million
B.$0.75 million
C.$0 since markets are efficient
D.Symmetrically distributed
解释：
B is correct. The expected payoff is the sum of probabilities times the payoff in each state of the world, or 83% x $5 + 17% x (—$20) = $4.15 — $3.40 = $0.75. Note that the distribution is highly asymmetric, with a small probability of a large loss.
3.40是在哪找到的……
