Although Fama and French (1992) and Lakonishok, Shleifer and Vishny (1994) show that a portfolio of high BM firms outperforms that of low BM firms, they provide two different explanations, namely, risk and mispricing explanations, respectively. Fama and French (1992) explain that the basic argument underlying risk-based concept is simply the fact that different types of stocks are exposed to different amount of systematic risk; and therefore, carry different expected returns. Specifically, they show that the variation of crosssectional stock returns can be explained by two different factors, namely BM ratio and firm size. They claim that bankruptcy risk or financial distress risk is represented by BM ratio, while firm size acts as a proxy of liquidity risks. High BM ratio means the market judges firm’s prospects to be poor relative to the entire market, so BM ratio may capture financial
distress effect. Thus, high BM firms are likely to have greater bankruptcy risks; and hence,
higher excess returns in compensation for higher additional risk. Nevertheless, this
explanation is less valid for low BM firms, since it is contrary to the fact that low BM stocks
are more risky than the stock market as a whole; and therefore, should generate high returns.
Alternatively, Lakonishok, Shielfer and Vishny (1994) argue that there is little
evidence that high BM stocks are fundamentally riskier. They claim that high BM stocks
produce superior returns because typical investors consistently overestimate future growth of
low BM stocks relative to high BM stocks. In other words, investors are extremely
pessimistic (optimistic) about high (low) BM stocks as they tie expectations of future growth
to past bad (good) growth/earnings; hence, they put excessive weight on the recent past for
prediction of future returns. They oversell the stocks that have recently performed poorly and
overbuy the stocks that have performed well. Therefore, these stocks are either underpriced
and have a high BM, or overpriced and have a low BM. This mispricing explanation implies
that typical investors make systematic errors in predicting future growth earnings of stocks;
therefore, one can exploit the mistakes of typical investors by purchasing high BM stocks and
shorting low BM stocks. This is a common judgment error and may explain the investor
preference of low BM stocks (growth stocks) over high BM stocks (value stocks). Their
empirical evidence also suggests that institutional investors prefer low BM stocks over high
BM stocks, and are willing to pay them at a premium price because they represent prudent
investments. LaPorta (1996) also supports this mispricing explanation.
Investors are often the victims of the mispricing effect. They often estimate firm’s
future prospect from past performance while ignoring the tendency of corporate profit growth
to revert to the mean. Fuller, Huberts, and Levinson (1993) explain that earnings growth
rates tend to revert to the mean quickly because of the nature of the capital markets. They
find that, although earnings per share (EPS) growth rate of high price-to-earnings (PE) group
substantially exceeds that of low PE group in the first year of portfolio formation, it
converges closely to the mean after only 4 years. Stated differently, investors are misled by
past growth and overlook the nature of business competition. Industries which are
experiencing the high growth tend to attract heavy competition by other firms. This
competitive process eventually results in lower growth rate and lower returns. Instead,
industries with low growth rate attract less capital from the market. Therefore, in order to
survive in the competition, management tries to achieve higher earnings by operating more
efficiently