Testing the joint stock market efficiency of OPEC countries

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Ebenezer Olubiyi
Eunice Oluganna
Segun K. Fakunmoju


The study investigates the joint market efficiency hypothesis of the OPEC countries by obtaining monthly stock price data from seven OPEC countries from January, 2005 to April, 2016.  The study confirms the risk-return tradeoff in the OPEC stock markets.  While most relationships are positive only a pair of country shows strong negative association   Results of both parametric and nonparametric tests indicate that all OPEC members’ monthly stock return, except Qatar, are not weak-efficient. This implies that not all OPEC stock markets are efficient.  Meanwhile, the study finds that current monthly stock return of one country member can be predicted using the historical monthly price movement of another OPEC member.  As a whole, the monthly stock price of OPEC countries are not jointly weak efficient.  Recommendations were offered based on these important discoveries.


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AFEGO, P. (2012) Weak form-efficiency of the Nigerian stock market: an empirical analysis (1984-2009). International Journal of Economics and Financial Issues, p. 340-347

ANDRIANTO, Y.; MIRZA, A. (2016) A testing of efficient markets hypothesis in Indonesia. Social and behvioural science, v. 219, p. 99-103.

AZAD, A. S. (2009) Random walk and efficiency tests in the Asia-Pacific foreign exchange markets: evidence from the post-Asian currency crisis data. Research in International Business and Finance, v. 23, n. 3, p. 322-338.

BROOKS, C. (2014) Introductory econometrics for finance, 3rd edition. Cambridge University Press, London.

CHARLES, A. I.; DAME, O. (2009) The random walk hypothesis for Chinese stock markets: evidence from variance ratio tests. Economic Systems, v. 33, n. 2, p. 117-126.

CHOW, K. V.; DENNING, K. C. (1993) A simple multiple variance ratio test. Journal of Econometrics, v. 58, p. 385-401.

DARRAT, A. F.; ZHONG, M. (2000) On testing the random walk hypothesis: a model-comparison approach. The Financial Review, v. 35, p. 105-124.

FAMA, E. F. (1970) Efficient capital markets: A review of theory and empirical Work. Journal of Finance, v. 25, n. 2, p. 383-417.

FAN, Y.; GENÇAY, R. (2010) Unit root tests with wavelet. Economic Theory, v. 26, p. 1305-1331.

GIMBA, V. K. (2012) Testing the weak-form efficiency market hypothesis: evidecne from Nigeria stock market. CBN Journal of Applied Statistics, v. 3, n. 1, p. 117-136.

GILMORE, C. G.,.; MCMANUS, G. M. (2003) Random-walk and efficiency tests of Central European equity markets. Managerial Finance, 2(4, p. 42 - 61.

GRAHAM, M., PELTOM¨AKI, J AND STURLUD ´OTTIR, H. (2015) Do market controls affect stock market efficiency? Lessons from Iceland. International Review of Financial Analysis, doi: 10.1016/j.irfa.2015.05.009.

GUIDI, F.; GUPTA, R. (2013) Are ASEAN stock market efficient? Evidence from univariate and multivariate variance ratio tests. Griffith Business Scholl Discussin Papers in Finance, p. 2011-13.

HUMPHREY, P.; LONT, D. (2005) A Variance-Ratio Test of the Random Walk Hypothesis for the New Zealand Share Market. Pacific Accounting Review, v. 17, n. 2, p. 53 - 71.

IM, K. S.; PERASAN, M. H.; SHIN, Y. (2003) Testing for unit roots in heterogenous panels. Journal of Econometrics, v. 115, n. 1, p. 53-74.

JAIN, P.; VYAS, V.; ROY, A. (2013) A study on weak form of market efficiency during the period of global financial crisis in the form of random walk on Indian capital market. Journal of Advances in Management Research, v. 10, n. 1, p. 122-138.

JAMAANIA, F.; ROCA, E. (2014) Are the regional Gulf stock markets weak-form efficient as single stock markets and as a regional stock market? Research in International Business and Finance, v. 33, p. 221-246

JARRETT, J. E. (2008) Random walk, capital market efficiency and predicting stock returns for Hong Kong Exchanges and Clearing Limited. Management Research News, v. 31, n. 2, p. 142-148.

KIM, J. H.; SAHMSUDDIN, A. (2008) Are Asian stock markets efficient? Evidence from new multiple variance ratio tests. Journal of Empirical Finance, v. 15, n. 3, p. 518-532.

LAGOARDE-SEGOT, T.; LUCEY, B. M. (2006) Efficiency in emerging markets—Evidence from the MENA region. International Financial Markets, Institutions and Money, v. 18, n. 1, p. 94-

LIU, C. Y.; HE, J. (1991) A Variance-Ratio Test of Random Walks in Foreign Exchange Rates. The Journal of Finance, v. 46, n. 2, p. 773-785.

LO, A. W.; MACKINLAY, A. C. (1988) Stock price do not follow random walks: evidence from specification test. Review of Financial Studies, v. 1, p. 41-66.

NNEJI, I. (2013) Efficiency of the Nigerian Capital Market; an Empirical Analysis. Research Journal of Finance and Accounting, v. 4, n. 4, p. 69-77.

NWODIBE, B. M. (2014) The random walk theory: an empirical test in the Nigerian capital market. Asian Economic and Financial Review, v. 4, n. 2, p. 1840-1848.

NWOSA, S.; OSENI, J. E. (2011) Efficient market hypothesis and Nigeria stock market. Research Journal in Finance and Accounting, v. 2, n. 12, p. 38-46.

OBAYAGBONA, J.; IGBINOSA, S. O. (2015) Test of random walk hypothesis in Nigeria stock market. Current Research Journal of Social Sciences, v. 7, n. 2, p. 27-36.

PANDEY, I. M. (2010) Financial management. New Delhi: Vikas Pubs.

PERASAN, M. H. (2007) A simple panel unit root test in the presence of cross sectional dependence. Journal of Applied Econometrics, v. 22, n. 2, p. 265-312.

SAMUELSON, P. A. (1965) Proof that properly anticipated prices fluctuate randomly. Industrial Management Review, v. 6, n. 2, p. 41-49

URQUHART, A.; MAGROARTY, F. (2016) Are stock markets really efficient? Evidence from adaptive market hypothesis. International Review of Financial Analysis, doi:10.1016/jirfa,.2016.06.011.

WRIGHT, J. H. (2000) Alternative variance-ratio tests using ranks and signs. Journal of Business and Economic Statistics, v. 18, n. 1, p. 1-9.

WORLD BANK (2018) Global Economic Prospect: Broad-based upturn, but for how long? The World Bank Group, Washington D.C.

TIWARI, A.; KYOPHILAVONG, P. (2014) New evidence from the random walk hypothesis for BRICs stock indices: a wavelet unit root test approach. Economic Modelling, v. 43, p. 38-41.

ZHANG, M.; CHENG, Q. (2005) An approach to VaR for capital markets with Gaussian mixture. Applied Mathematics and Computation, v. 168, n. 2, p. 1079-1085.