What is the Efficient Markets Hypothesis (EMH),and what are its three forms? What evidence supports the EMH? What evidence casts doubt onthe EMH?

Definition Definition Degree to which financial markets incorporate all available information into the prices of assets. In a more efficient market, the prices reflect the available information more than that in a weak efficient market. It is difficult for investors to outperform the market in a strong efficient market. This is because all the available information is already discounted in the asset's price. However, in a weak-form efficiency, the market does not reflect all information in the asset's price. As a result, it becomes easier to generate better returns in a weak form or an inefficient market.