Structural Breaks, Long Memory, or Unit Roots in Stock Prices: Evidence from Emerging Markets

Year 2015, Volume: 7 Issue: 1, 13 - 33, 01.04.2015

Mehmet Balcilar Esin Cakan Zeynel Abidin Ozdemir

https://doi.org/10.33818/ier.278038

Cited By: 5

Abstract

This paper investigates whether daily stock price indices from fourteen emerging markets are random walk (unit root) or mean reverting long memory processes. We use an efficient statistical framework that tests for random walks in the presence of multiple structural breaks at unknown dates. This approach allows us to investigate a broader range of persistence than that allowed by the I(0)/I(1) paradigm about the order of integration, which is usually implemented for testing the random walk hypothesis in stock market indices. Our approach extends Robinson’s (1994) efficient test of unit root against fractional integration to allow for multiple endogenously determined structural breaks. For almost all countries, we find support for the random walk hypothesis, with the exception of four stock markets, where weak evidence of mean reverting long memory exist. Structural breaks have impact on the unit root behavior only for Mexico; for all other 11 markets unit roots exist even when structural breaks are not taken into account. In order to check the robustness of our results, we use the two-step feasible exact local Whittle (FELW2ST) estimator of Shimotsu (2010), which allows for polynomial trends, non-normal distributions, and non-stationarity. The results from the semi-parametric FELW2ST approach shows that, except for Mexico, stock price indices of 13 emerging markets are not mean reverting.

Keywords

Emerging Markets, Random Walk, Structural Breaks, Market Liberalization.

References

• Bai, J. and P. Perron (1998). Estimating and Testing Linear Models with Multiple Structural Changes. Econometrica 66, 47-78.
• Bekaert, G. and C.R. Harvey (2000). Foreign speculators and emerging equity markets. Journal of Finance, 55, 565-613.
• Bekaert, G., C.R. Harvey and R.L. Lumsdaine (2002a). Dating the integration of world equity markets. Journal of Financial Economics, 65, 203-247.
• Bekaert, G., C.R. Harvey, R.L. Lumsdaine and L. Robin (2002b). The dynamics of emerging market equity flows. Journal of International Money and Finance, 21, 295-350.
• Beran, J., R.J. Bhansali and D. Ocker (1998). On unified model selection for stationary and non-stationary short- and long-memory autoregressive processes. Biometrika, 85, 921- 934.
• Campbell, J.Y. and P. Perron (1991). Pitfalls and Opportunities: What Macroeconomists Should Know About Unit Roots. NBER Macroeconomics Annual 1991, 6, 141-220.
• Chaudhuri, K. and Y. Wu (2003). Random walk versus breaking trend in stock prices: Evidence from emerging markets. Journal of Banking & Finance, 27, 575-592.
• DeJong, D.N., J. C. Nankervis, N.E. Savin and C.H. Whiteman (1992). The power problems of unit root test in time series with autoregressive errors. Journal of Econometrics, 53, 323-343.
• Dickey, D. and W.A. Fuller (1979). Distributions of the Estimators for Autoregressive Time Series with a Unit Root. Journal of the American Statistical Association, 74, 427-431.
• Dickey, D. and W.A. Fuller (1981). Likelihood ratio statistics for autoregressive time series with a unit root. Econometrica, 49, 1057-1071.
• Diebold, F.X. and G.D. Rudebusch (1991). On the power of Dickey-Fuller tests against fractional alternatives. Economics Letters, 35, 155-160.
• Errunza, V., E. Losq and P. Padmanabhan (1992). Tests of integration, mild segmentation and segmentation hypotheses. Journal of Banking and Finance, 16, 949-972.
• Fama, E.F. (1965). The Behavior of Stock Market Prices. Journal of Business Finance and Accounting, 38, 34-105.
• Fama, E.F. (1970). Multiperiod consumption-investment decisions. American Economic Review, 60, 163-174.
• Gil-Alana, L.A. and P.M. Robinson (1997). Testing of Unit Roots and Other Nonstationary Hypotheses in Macroeconomic Time Series. Journal of Econometrics, 80, 241-268.
• Gil-Alana, L.A. (1999). Testing of Fractional Integration with Monthly Data. Economic Modelling, 16, 613-629.
• Gil-Alana, L.A. (2000). A Fractionally Integrated Model with a Mean Shift for the US and the UK Real Oil Prices. Economic Modelling, 18, 643-658.
• Gil-Alana, L.A. (2001). Testing of Stochastic Cycles in Macroeconomic Time Series. Journal of Time Series Analysis, 22, 411-430.
• Gil-Alana, L.A. (2002). Structural Breaks and Fractional Integration in the US Output and Unemployment Rate. Economics Letters, 77, 79-84.
• Gil-Alana, L.A. (2003). Testing of unit roots and other fractionally integrated hypothesis in the presence of structural breaks. Empirical Economics, 28, 101–13.
• Gil-Alana, L.A. (2008). Fractional Integration and Structural Breaks at Unknown Periods of Time. Journal of Time Series Analysis, 29, 163-185.
• Granger, C.W.J. and R. Joyeux (1980). An Introduction to Long Memory Time Series Models and Fractional Differencing. Journal of Time Series Analysis, 1, 15 29.
• Hassler, U. and J. Wolters (1994). On the power of unit root tests against fractional alternatives. Economics Letters, 1-5.
• Henry, P.B. (2000). Stock market liberalization, economic reform, and emerging market equity prices. Journal of Finance, 55, 529-564.
• Hosking, J. (1981). Fractional Differencing. Biometrika, 68, 165-176.
• Kawakatsu, H. and M. Morey (1999). Stock market opening and return predictability in emerging stock markets. Mimeo: Fordham University.
• Lee, D. and P. Schmidt (1996). On the Power of the KPSS Test of Stationarity Against Fractionally-Integrated Alternatives. Journal of Econometrics, 73, 285-302.
• Newey, W. and K. West (1994). Automatic Lag Selection in Covariance Matrix Estimation. Review of Economic Studies, 61, 631-653.
• Ozdemir, Z.A. (2008). Efficient market hypothesis: evidence from a small open-economy. Applied Economics, 40, 633–641.
• Perron, P. (1989). The Great Crash, the Oil-Price Shock, and the Unit Root Hypothesis. Econometrica, 57, 361-1401.
• Phillips, P.C.B. and P. Perron (1988). Testing for a Unit Root in a Time Series Regression. Biometrika, 75, 335-346.
• Phillips, P.C.B. and V. Solo (1992). Asymptotics for Linear Processes. Annals of Statistics, 20, 971–1001.
• Robinson, P.M. (1994). Efficient Tests of Nonstationary Hypotheses. Journal of the American Statistical Association, 89, 1420-1437.
• Said, S.E. and D.A. Dickey (1984). Testing for unit roots in autoregressive moving average models of unknown order. Biometrika, 71, 599–607.
• Schwarz, G. (1978). Estimating the dimension of a model. Annals of Statistics, 6, 461–4.
• Shimotsu, K. (2010). Exact Local Whittle Estimation of Fractional Integration with Unknown Mean and Time Trend. Econometric Theory, 26, 501-540.
• Stulz, R.M. and W. Wasserfallen (1995). Foreign equity investment restrictions, capital flight, and shareholder wealth maximization: Theory and evidence. Review of Financial Studies, 8, 1019–1057.
• Zivot, E. and D.W.K. Andrews (1992). Further evidence on the great crash, the oil price shock, and the unit root hypothesis. Journal of Business and Economic Statistics, 10, 251-270.