Random Walk Tests for the Lisbon Stock Market
This paper reports the results of tests on the weak-form market efficiency applied to the PSI-20 index prices of the Lisbon Stock Market from January 1993 to December 2006. As an emerging stock market, it is unlikely that it is fully information-efficient, but we show that the level of weak-form efficiency has increased in recent years. We use a serial correlation test, a runs test, an augmented Dickey-Fuller test and the multiple variance ratio test proposed by Lo and MacKinlay (1988) for the hypothesis that the stock market index follows a random walk. Non-trading or infrequent trading is not an issue because the PSI-20 only includes the 20 most traded shares. The tests are performed using daily, weekly and monthly returns for the whole period and for five sub-periods which reflect different trends in the market. We find mixed evidence, but on the whole, our results show that the Portuguese stock market index has been approaching a random walk behavior since year 2000, with a decrease in the serial dependence of returns.
|Date of creation:||2007|
|Date of revision:|
|Contact details of provider:|| Postal: Department of Economics, ISEG - School of Economics and Management, University of Lisbon, Rua do Quelhas 6, 1200-781 LISBON, PORTUGAL|
Web page: https://aquila1.iseg.ulisboa.pt/aquila/departamentos/EC
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:
- James G. MacKinnon, 1992.
"Approximate Asymptotic Distribution Functions for Unit Roots and Cointegration Tests,"
861, Queen's University, Department of Economics.
- MacKinnon, James G, 1994. "Approximate Asymptotic Distribution Functions for Unit-Root and Cointegration Tests," Journal of Business & Economic Statistics, American Statistical Association, vol. 12(2), pages 167-76, April.
- Nicolaas Groenewold & Mohamed Ariff, 1998. "The Effects of De-Regulation on Share-Market Efficiency in the Asia-Pacific," International Economic Journal, Taylor & Francis Journals, vol. 12(4), pages 23-47.
- Graham Smith & Keith Jefferis & Hyun-Jung Ryoo, 2002. "African stock markets: multiple variance ratio tests of random walks," Applied Financial Economics, Taylor & Francis Journals, vol. 12(7), pages 475-484.
- Abraham Abraham, 2002. "Testing the Random Walk Behavior and Efficiency of the Gulf Stock Markets," The Financial Review, Eastern Finance Association, vol. 37(3), pages 469-480, 08.
- José Carlos Dias & Luís Lopes & Vitor Martins & José Manuel Benzinho, 2004. "Efficiency tests in the Iberian stock markets," Finance 0406001, EconWPA.
- Fama, Eugene F & French, Kenneth R, 1988. "Permanent and Temporary Components of Stock Prices," Journal of Political Economy, University of Chicago Press, vol. 96(2), pages 246-73, April.
- M. Magnusson & B. Wydick, 2002. "How Efficient are Africa's Emerging Stock Markets?," Journal of Development Studies, Taylor & Francis Journals, vol. 38(4), pages 141-156.
- Fama, Eugene F, 1970. "Efficient Capital Markets: A Review of Theory and Empirical Work," Journal of Finance, American Finance Association, vol. 25(2), pages 383-417, May.
- Jorge L. Urrutia, 1995. "Tests Of Random Walk And Market Efficiency For Latin American Emerging Equity Markets," Journal of Financial Research, Southern Finance Association;Southwestern Finance Association, vol. 18(3), pages 299-309, 09.
- Graham Smith & Hyun-Jung Ryoo, 2003. "Variance ratio tests of the random walk hypothesis for European emerging stock markets," The European Journal of Finance, Taylor & Francis Journals, vol. 9(3), pages 290-300.
When requesting a correction, please mention this item's handle: RePEc:ise:isegwp:wp142007. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Vitor Escaria)
If references are entirely missing, you can add them using this form.