Testing Semi-strong Form Efficiency of Stock Market
AbstractThe efficient market hypothesis suggests that stock markets are “informationally efficient”. That is, any new information relevant to the market is spontaneously reflected in the stock prices. A consequence of this hypothesis is that past prices cannot have any predictive power for future prices once the current prices have been used as an explanatory variable. In other words the change in future prices depends only on arrival of new information that was unpredictable today hence it is based on surprise information. Another consequence of this hypothesis is that arbitrage opportunities are wiped out instantaneously. Empirical tests of the efficient market hypothesis actually test for these consequences in various ways. Some of them have been summarised in earlier chapters. These tests generally could not conclusively accept the random-walk hypothesis of stock returns even when GARCH effects were accounted for. Many studies have found empirical regularities that are contrary to the efficient market hypothesis. For example, the monthly, weekly and daily returns on stocks tend to exhibit discernable patterns, such as seasonal affects, month of the year affect, day of the week affect, hourly affect etc. In case of Pakistan’s stock markets too such affects are identified. Such as the Ramadan affect [see Hussain and Uppal (1999)], seasonal effects and day of the week affect. Further, the wide spread use of “technical analysis” among stock traders and their ability to predict to some extent the direction of movements in the prices of individual stocks over medium term testifies to the existence of patterns and seasonal trends.
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Bibliographic InfoArticle provided by Pakistan Institute of Development Economics in its journal The Pakistan Development Review.
Volume (Year): 40 (2001)
Issue (Month): 4 ()
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- Schwert, G William, 1981. "The Adjustment of Stock Prices to Information about Inflation," Journal of Finance, American Finance Association, vol. 36(1), pages 15-29, March.
- Leland, Hayne E, 1992.
"Insider Trading: Should It Be Prohibited?,"
Journal of Political Economy,
University of Chicago Press, vol. 100(4), pages 859-87, August.
- Rozeff, Michael S. & Kinney, William Jr., 1976. "Capital market seasonality: The case of stock returns," Journal of Financial Economics, Elsevier, vol. 3(4), pages 379-402, October.
- Jaffe, Jeffrey F, 1974. "Special Information and Insider Trading," The Journal of Business, University of Chicago Press, vol. 47(3), pages 410-28, July.
- Aslam Farid & Javed Ashraf, 1995. "Volatility at Karachi Stock Exchange," The Pakistan Development Review, Pakistan Institute of Development Economics, vol. 34(4), pages 651-657.
- Fazal Husain, 1997.
"The Random Walk Model in the Pakistani Equity Market: An Examination,"
The Pakistan Development Review,
Pakistan Institute of Development Economics, vol. 36(3), pages 221-240.
- Husain, Fazal, 1997. "The Random Walk Model in the Pakistani Equity market: An Examination," MPRA Paper 5034, University Library of Munich, Germany.
- David M. Cutler & James M. Poterba & Lawrence H. Summers, 1988.
"What Moves Stock Prices?,"
NBER Working Papers
2538, National Bureau of Economic Research, Inc.
- Penman, Stephen H., 1987. "The distribution of earnings news over time and seasonalities in aggregate stock returns," Journal of Financial Economics, Elsevier, vol. 18(2), pages 199-228, June.
- Fama, Eugene F, et al, 1969. "The Adjustment of Stock Prices to New Information," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 10(1), pages 1-21, February.
- Husain, Fazal, 1998.
"A Seasonality in the Pakistani Equity Market: The Ramadhan Effect,"
5032, University Library of Munich, Germany.
- Fazal Husain, 1998. "A Seasonality in the Pakistani Equity Market: The Ramadhan Effect," The Pakistan Development Review, Pakistan Institute of Development Economics, vol. 37(1), pages 77-81.
- French, Kenneth R. & Roll, Richard, 1986. "Stock return variances : The arrival of information and the reaction of traders," Journal of Financial Economics, Elsevier, vol. 17(1), pages 5-26, September.
- Niederhoffer, Victor, 1971. "The Analysis of World Events and Stock Prices," The Journal of Business, University of Chicago Press, vol. 44(2), pages 193-219, April.
- Ehsan Ahmed & J. Barkley Rosser, Jr., 1995. "Non-linear Speculative Bubbles in the Pakistani Stock Market," The Pakistan Development Review, Pakistan Institute of Development Economics, vol. 34(1), pages 25-41.
- Mitchell, Mark L & Mulherin, J Harold, 1994. " The Impact of Public Information on the Stock Market," Journal of Finance, American Finance Association, vol. 49(3), pages 923-50, July.
- Abid Hameed & Hammad Ashraf, 2006. "Stock Market Volatility and Weak-form Efficiency: Evidence from an Emerging Market," The Pakistan Development Review, Pakistan Institute of Development Economics, vol. 45(4), pages 1029-1040.
- Muhammad Akbar & Humayun Habib Baig, 2010. "Reaction of Stock Prices to Dividend Announcements and Market Efficiency in Pakistan," Lahore Journal of Economics, Department of Economics, The Lahore School of Economics, vol. 15(1), pages 103-125, Jan-Jun.
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