...Topic：Stock price momentum: Jegadeesh and Titman (1993) Momentum anomaly and EMH Anomaly is a stock return deviation that challenge efficient market hypothesis (EMH). Jegadeesh and Titman (1993) theorise price momentum anomaly in the stock market for the first time. It contradicted to efficient market hypothesis thereby is widely debated. EMH states that no consistent excess return can be achieved since security prices fully reflect all available information (Fama 1970). Therefore, future prices cannot be predicted through technical analysis of past prices. If the hypothesis is true, passive investment strategy ought to be taken, because it is impossible to get abnormal return by aggressive trading. However, Jegadeesh and Titman show that stocks performed well over the previous 3 to 12 months tend to continue to perform well over 3 to 12 months holding periods. Buy past winners and short past losers earned statistically significant positive return of averaging 12.01% per year. Predictable price patterns and excess returns contradict the efficient market hypothesis. Investors and fund managers perform actively in pursuing abnormal profits. Literature review and the reason of anomaly A large number of literatures illustrate that momentum anomaly exist. Some important literatures are Chan, Jegadeesh and Lakonishok (1996), Conrad and Kaul (1998) and Moskowitz and Grinblatt (1999). Lee and Swaminathan (2000) find high past turnover stocks exhibit larger magnitude of momentum but shorter...
Words: 1632 - Pages: 7
...price momentum: Jegadeesh and Titman (1993) Momentum anomaly and EMH Anomaly is a stock return deviation that challenge efficient market hypothesis (EMH). Jegadeesh and Titman (1993) theorise price momentum anomaly in the stock market for the first time. It contradicted to efficient market hypothesis thereby is widely debated. EMH states that no consistent excess return can be achieved since security prices fully reflect all available information (Fama 1970). Therefore, future prices cannot be predicted through technical analysis of past prices. If the hypothesis is true, passive investment strategy ought to be taken, because it is impossible to get abnormal return by aggressive trading. However, Jegadeesh and Titman show that stocks performed well over the previous 3 to 12 months tend to continue to perform well over 3 to 12 months holding periods. Buy past winners and short past losers earned statistically significant positive return of averaging 12.01% per year. Predictable price patterns and excess returns contradict the efficient market hypothesis. Investors and fund managers perform actively in pursuing abnormal profits. Literature review and the reason of anomaly A large number of literatures illustrate that momentum anomaly exist. Some important literatures are Chan, Jegadeesh and Lakonishok (1996), Conrad and Kaul (1998) and Moskowitz and Grinblatt (1999). Lee and Swaminathan (2000) find high past turnover stocks exhibit larger magnitude of momentum but shorter...
Words: 1631 - Pages: 7
...October 28, 2011 The Efficient-Market Hypothesis and the Financial Crisis Burton G. Malkiel* Abstract The world-wide financial crisis of 2008-2009 has left in its wake severely damaged economies in the United States and Europe. The crisis has also shaken the foundations of modern-day financial theory, which rested on the proposition that our financial markets were basically efficient. Critics have even suggested that the efficient--market–hypotheses (EMH) was in large part, responsible for the crises. This paper argues that the critics of EMH are using a far too restrictive interpretation of what EMH means. EMH does not imply that asset prices are always “correct.” Prices are always wrong, but no one knows for sure if they are too high or too low. EMH does not imply that bubbles in asset prices are impossible nor does it deny that environmental and behavioral factors cannot have profound influences on required rates of return and risk premiums. At its core, EMH implies that arbitrage opportunities for riskless gains do not exist in an *Princeton University. I am indebted to Alan Blinder and to the participants in the Russell Sage Conference on Economic Lessons From the Financial Crisis for extremely helpful comments. 2 efficiently functioning market and if they do appear from time to time that they do not persist. The evidence is clear that this version of EMH is strongly supported by the data. EMH can comfortably coexist with behavior finance, and the insights of Hyman...
Words: 11209 - Pages: 45
...consistent with each of the model’s five central predictions: (1) Since constrained investors bid up high-beta assets, high beta is associated with low alpha, as we find empirically for U.S. equities, 20 international equity markets, Treasury bonds, corporate bonds, and futures; (2) A betting-against-beta (BAB) factor, which is long leveraged lowbeta assets and short high-beta assets, produces significant positive risk-adjusted returns; (3) When funding constraints tighten, the return of the BAB factor is low; (4) Increased funding liquidity risk compresses betas toward one; (5) More constrained investors hold riskier assets. * Andrea Frazzini is at AQR Capital Management, Two Greenwich Plaza, Greenwich, CT 06830, e-mail: andrea.frazzini@aqr.com; web: http://www.econ.yale.edu/~af227/ . Lasse H. Pedersen is at New York University, AQR, NBER, and CEPR, 44 West Fourth Street, NY 10012-1126; e-mail: lpederse@stern.nyu.edu; web: http://www.stern.nyu.edu/~lpederse/. We thank Cliff Asness, Aaron Brown, John Campbell, Kent Daniel, Gene Fama, Nicolae Garleanu, John Heaton (discussant), Michael Katz, Owen Lamont, Michael Mendelson, Mark Mitchell, Matt Richardson, Tuomo Vuolteenaho and Robert Whitelaw for helpful comments and discussions as well as seminar participants at Columbia University, New York University, Yale University, Emory University, University of Chicago Booth, Kellogg School of Management, Harvard University, NBER Behavioral Economics 2010, the 2010 Annual Management Conference...
Words: 29988 - Pages: 120
