Chapter 7: Stocks and Other Assets 66
and transactions costs may have a higher return after taxes and
transactions costs if it has less trading and less capital gain
3. Historical Returns and Stock Prices
a) Data beginning in 1875 on the S&P index show that real stock prices
change dramatically over time, with huge losses over some periods
B. Data Bank: The Explosion of Tech Stocks in the Late 1990s and Their
Implosion in the Early 2000s
1. The NASDAQ stock index tripled in value from October 1998 to March
2000 because of investor excitement over tech stocks that was not
justi”ed
2. Without the pro”ts to back up such high stock prices, investors realized
that the prices were not justi”ed, and stock prices plummeted in 2000;
see Figure 7.A
C. How Can an Investor Pro”t in the Stock Market?
1. If there are many buyers and sellers, the stock market conforms to the
stock prices follow a random walk
3. Are Stock Prices Unpredictable?
a) Research shows that stock prices are somewhat predictable:
relationships exist between stock prices at different times
b) So either markets are ine9cient or investors care about risk
4. Are Stock Returns Predictable Only Because of Risk?
a) Anomalies exist even after researchers carefully account for risk
b) Can an investor pro”t from an anomaly?
c) Models of risk may not be accurate (CAPM, APT)