Which of the following most appears to contradict the proposition that the stock market is
weakly efficient? Explain.
a. Over 25% of mutual funds outperform the market on average.
b. Stocks that had positive returns over the past six months tend to have positive returns
over the following six months.
c. Stocks announcing positive earnings have positive abnormal returns over the 3
months following the earnings announcement.
d. Insiders earn abnormal trading profits.