Explanation : In an inefficient market, investors might be able to earn superior risk
adjusted returns since opportunities for it exist in the market e.g. due to
mispricing. However, in an efficient market a passive investment strategy
would be preferred to an active strategy for its lower costs and because
opportunities for earning superior risk adjusted returns in an efficient
market are negligible.
Explanation : The first two statements are correct as momentum anomalies relate to
short-term price patterns, typically resulting from investor overreaction in
response to the release of unexpected public information.
Explanation : A contradiction to weak-form efficiency occurs when securities that have
experienced high returns in the short term tend to continue to generate
higher returns in subsequent periods. If investors can trade on the basis of
momentum and earn abnormal profits, then this anomaly contradicts the
weak form of the efficient market hypothesis because it represents a
pattern in prices that can be exploited by simply using historical price
information.