Suggested Solution to Homework 4, part 1 and part 2
Chapter 11 7.(20 points) The following effects seem to suggest predictability within equity markets and thus disprove the Efficient Market Hypothesis. However, consider the following: a. Multiple studies suggest that “value” stocks (measured often by low P/E multiples) earn higher returns over time than “growth” stocks (high P/E multiples). This could suggest a strategy for earning higher returns over time. However, another rational argument may be that traditional forms of CAPM (such as Sharpe’s model) do not fully account for all risk factors which affect a firm’s price level. A firm viewed as riskier may have a lower price and thus P/E multiple. b. The book-to-market effect suggests that an investor can earn excess returns by investing in companies with high book value (the value of a firm’s assets minus its liabilities divided by the number of shares outstanding) to market value. A study by Fama and French 1 suggests that book-to-market value reflects a risk factor that is not accounted for by traditional one variable CAPM. For example, companies experiencing financial distress see the ratio of book to market value increase. Thus a more complex CAPM which includes book-to-market value as an explanatory variable should be used to test market anomalies. c. Stock price momentum can be positively correlated with past performance (short to intermediate horizon) or negatively correlated (long horizon). Historical data seem to imply statistical significance to these patterns. Explanations for this include a bandwagon effect or the behavioralists’ (see Chapter 12) explanation that there is a tendency for investors to underreact to new information, thus producing a positive serial correlation. However, statistical significance does not imply economic significance. Several studies which included transaction costs in the