IDEAS home Printed from
   My bibliography  Save this paper

Panel Data Tests of PPP. A Critical Overview


  • Caporale, Guglielmo Maria

    (London South Bank University)

  • Cerrato, Mario

    (London Metropolitan University)


This paper reviews panel unit root and cointegration tests in the context of PPP. It highlights various drawbacks of existing methods. First, unit root tests suffer from severe size distortions in the presence of negative moving average errors. Second, the common demeaning procedure to correct for the bias resulting from homogeneous cross-sectional dependence is not effective; more worryingly, it introduces cross-correlation when it is not already present. Third, standard corrections for the case of heterogeneous cross-sectional dependence do not generally produce consistent estimators. Fourth, if there is between-group correlation in the innovations, the SURE estimator is affected by similar problems to FGLS methods, and does not necessarily outperform OLS. Finally, cointegration between different groups in the panel could also be a source of size distortions. We offer some empirical guidelines to deal with these problems, but conclude that panel methods are unlikely to solve the PPP puzzle.

Suggested Citation

  • Caporale, Guglielmo Maria & Cerrato, Mario, 2004. "Panel Data Tests of PPP. A Critical Overview," Economics Series 159, Institute for Advanced Studies.
  • Handle: RePEc:ihs:ihsesp:159

    Download full text from publisher

    File URL:
    File Function: First version, 2004
    Download Restriction: no

    Other versions of this item:

    References listed on IDEAS

    1. John Y. Campbell & Pierre Perron, 1991. "Pitfalls and Opportunities: What Macroeconomists Should Know About Unit Roots," NBER Chapters,in: NBER Macroeconomics Annual 1991, Volume 6, pages 141-220 National Bureau of Economic Research, Inc.
    2. Kenneth Rogoff, 1996. "The Purchasing Power Parity Puzzle," Journal of Economic Literature, American Economic Association, vol. 34(2), pages 647-668, June.
    3. Jushan Bai & Serena Ng, 2002. "Determining the Number of Factors in Approximate Factor Models," Econometrica, Econometric Society, vol. 70(1), pages 191-221, January.
    4. Wu, Yangru, 1996. "Are Real Exchange Rates Nonstationary? Evidence from a Panel-Data Test," Journal of Money, Credit and Banking, Blackwell Publishing, vol. 28(1), pages 54-63, February.
    5. Caner, M. & Kilian, L., 2001. "Size distortions of tests of the null hypothesis of stationarity: evidence and implications for the PPP debate," Journal of International Money and Finance, Elsevier, vol. 20(5), pages 639-657, October.
    6. Lyhagen, Johan, 2000. "Why not use standard panel unit root test for testing PPP," SSE/EFI Working Paper Series in Economics and Finance 413, Stockholm School of Economics.
    7. Papell, David H., 1997. "Searching for stationarity: Purchasing power parity under the current float," Journal of International Economics, Elsevier, vol. 43(3-4), pages 313-332, November.
    8. Canzoneri, Matthew B. & Cumby, Robert E. & Diba, Behzad, 1999. "Relative labor productivity and the real exchange rate in the long run: evidence for a panel of OECD countries," Journal of International Economics, Elsevier, vol. 47(2), pages 245-266, April.
    9. Froot, Kenneth A. & Rogoff, Kenneth, 1995. "Perspectives on PPP and long-run real exchange rates," Handbook of International Economics,in: G. M. Grossman & K. Rogoff (ed.), Handbook of International Economics, edition 1, volume 3, chapter 32, pages 1647-1688 Elsevier.
    10. Lopez, Claude & Murray, Christian J & Papell, David H, 2005. "State of the Art Unit Root Tests and Purchasing Power Parity," Journal of Money, Credit and Banking, Blackwell Publishing, vol. 37(2), pages 361-369, April.
    11. Im, Kyung So & Pesaran, M. Hashem & Shin, Yongcheol, 2003. "Testing for unit roots in heterogeneous panels," Journal of Econometrics, Elsevier, vol. 115(1), pages 53-74, July.
    12. Karlsson, Sune & Lothgren, Mickael, 2000. "On the power and interpretation of panel unit root tests," Economics Letters, Elsevier, vol. 66(3), pages 249-255, March.
    13. Koedijk, Kees G. & Schotman, Peter, 1990. "How to beat the random walk : An empirical model of real exchange rates," Journal of International Economics, Elsevier, vol. 29(3-4), pages 311-332, November.
    14. Coakley, Jerry & Fuertes, Ana Maria, 1997. "New panel unit root tests of PPP," Economics Letters, Elsevier, vol. 57(1), pages 17-22, November.
    15. Peter Phillips & Hyungsik Moon, 2000. "Nonstationary panel data analysis: an overview of some recent developments," Econometric Reviews, Taylor & Francis Journals, vol. 19(3), pages 263-286.
    16. Murray, Christian J. & Papell, David H., 2002. "The purchasing power parity persistence paradigm," Journal of International Economics, Elsevier, vol. 56(1), pages 1-19, January.
    17. Paul Hallwood & Ronald MacDonald, 2008. "International Money and Finance," Working papers 2008-02, University of Connecticut, Department of Economics.
    18. Anindya Banerjee & Massimiliano Marcellino & Chiara Osbat, 2005. "Testing for PPP: Should we use panel methods?," Empirical Economics, Springer, vol. 30(1), pages 77-91, January.
    19. Suzanne McCoskey & Chihwa Kao, 1998. "A residual-based test of the null of cointegration in panel data," Econometric Reviews, Taylor & Francis Journals, vol. 17(1), pages 57-84.
    20. Engle, Robert & Granger, Clive, 2015. "Co-integration and error correction: Representation, estimation, and testing," Applied Econometrics, Publishing House "SINERGIA PRESS", vol. 39(3), pages 106-135.
    21. Larsson, Rolf & Lyhagen, Johan, 1999. "Likelihood-Based Inference in Multivariate Panel Cointegration Models," SSE/EFI Working Paper Series in Economics and Finance 331, Stockholm School of Economics.
    22. Serena Ng & Pierre Perron, 2001. "LAG Length Selection and the Construction of Unit Root Tests with Good Size and Power," Econometrica, Econometric Society, vol. 69(6), pages 1519-1554, November.
    23. Peter C. B. Phillips & Hyungsik R. Moon, 1999. "Linear Regression Limit Theory for Nonstationary Panel Data," Econometrica, Econometric Society, vol. 67(5), pages 1057-1112, September.
    24. Sargan, J D & Bhargava, Alok, 1983. "Maximum Likelihood Estimation of Regression Models with First Order Moving Average Errors When the Root Lies on the Unit Circle," Econometrica, Econometric Society, vol. 51(3), pages 799-820, May.
    25. Mark, Nelson C., 1990. "Real and nominal exchange rates in the long run: An empirical investigation," Journal of International Economics, Elsevier, vol. 28(1-2), pages 115-136, February.
    26. Coakley, Jerry & Fuertes, Ana-Marie, 2000. "Is There a Base Currency Effect in Long-Run PPP?," International Journal of Finance & Economics, John Wiley & Sons, Ltd., vol. 5(4), pages 253-263, October.
    27. Peter C. B. Phillips & Donggyu Sul, 2003. "Dynamic panel estimation and homogeneity testing under cross section dependence *," Econometrics Journal, Royal Economic Society, vol. 6(1), pages 217-259, June.
    28. Larsson, Rolf & Lyhagen, Johan, 2000. "Testing for common cointegrating rank in dynamic panels," SSE/EFI Working Paper Series in Economics and Finance 378, Stockholm School of Economics.
    29. MacDonald, Ronald, 1996. "Panel unit root tests and real exchange rates," Economics Letters, Elsevier, vol. 50(1), pages 7-11, January.
    30. S. Illeris & G. Akehurst, 2002. "Introduction," The Service Industries Journal, Taylor & Francis Journals, vol. 22(1), pages 1-3, January.
    31. Leybourne, S J & McCabe, B P M, 1994. "A Consistent Test for a Unit Root," Journal of Business & Economic Statistics, American Statistical Association, vol. 12(2), pages 157-166, April.
    32. O'Connell, Paul G. J., 1998. "The overvaluation of purchasing power parity," Journal of International Economics, Elsevier, vol. 44(1), pages 1-19, February.
    33. Oh, Keun-Yeob, 1996. "Purchasing power parity and unit root tests using panel data," Journal of International Money and Finance, Elsevier, vol. 15(3), pages 405-418, June.
    34. Enders, Walter & Falk, Barry, 1998. "Threshold-autoregressive, median-unbiased, and cointegration tests of purchasing power parity," International Journal of Forecasting, Elsevier, vol. 14(2), pages 171-186, June.
    35. Jerry Coakley & Ana-Maria Fuertes & Ron Smith, 2002. "A Principal Components Approach to Cross-Section Dependence in Panels," 10th International Conference on Panel Data, Berlin, July 5-6, 2002 B5-3, International Conferences on Panel Data.
    36. Johansen, Soren, 1988. "Statistical analysis of cointegration vectors," Journal of Economic Dynamics and Control, Elsevier, vol. 12(2-3), pages 231-254.
    37. Banerjee, Anindya, 1999. " Panel Data Unit Roots and Cointegration: An Overview," Oxford Bulletin of Economics and Statistics, Department of Economics, University of Oxford, vol. 61(0), pages 607-629, Special I.
    Full references (including those not matched with items on IDEAS)


    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.

    Cited by:

    1. Herzer, Dierk, 2014. "Unions and income inequality: a heterogenous cointegration and causality analysis," Working Paper 146/2014, Helmut Schmidt University, Hamburg.
    2. Guglielmo Maria Caporale & Christoph Hanck, 2010. "Are PPP tests erratically behaved? Some panel evidence," International Review of Applied Economics, Taylor & Francis Journals, vol. 24(2), pages 203-221.
    3. Luis Alberiko Gil-Alaña & Guiglielmo Maria Caporale, 2012. "Testing the PPP Hypothesis in the Sub-Saharan Countries," NCID Working Papers 10/2012, Navarra Center for International Development, University of Navarra.
    4. Guglielmo Maria Caporale & Christoph Hanck, 2009. "Cointegration tests of PPP: do they also exhibit erratic behaviour?," Applied Economics Letters, Taylor & Francis Journals, vol. 16(1), pages 9-15.
    5. repec:bbz:fcpbbr:v:9:y:2012:i:4:p:51-86 is not listed on IDEAS
    6. Martin Wagner, 2008. "On PPP, unit roots and panels," Empirical Economics, Springer, vol. 35(2), pages 229-249, September.
    7. Herzer, Dierk, 2015. "The long-run effect of foreign direct investment on total factor productivity in developing countries: A panel cointegration analysis," Annual Conference 2015 (Muenster): Economic Development - Theory and Policy 112827, Verein für Socialpolitik / German Economic Association.
    8. Woo, Kai-Yin & Lee, Shu-Kam, 2009. "Detecting intra-national PPP model in China: A median-unbiased estimation approach," Economic Modelling, Elsevier, vol. 26(5), pages 1029-1032, September.
    9. Dierk Herzer & Holger Strulik, 2017. "Religiosity and income: a panel cointegration and causality analysis," Applied Economics, Taylor & Francis Journals, vol. 49(30), pages 2922-2938, June.
    10. Herzer, Dierk, 2014. "The long-run relationship between trade and population health: evidence from five decades," Annual Conference 2014 (Hamburg): Evidence-based Economic Policy 100441, Verein für Socialpolitik / German Economic Association.
    11. Bahram Adrangi & Mary E. Allender & Kambiz Raffiee, 2011. "Exchange Rates and Inflation Rates: Exploring Nonlinear Relationships," Review of Economics & Finance, Better Advances Press, Canada, vol. 1, pages 1-16, April.
    12. Cerrato, Mario & Sarantis, Nicholas, 2007. "A bootstrap panel unit root test under cross-sectional dependence, with an application to PPP," Computational Statistics & Data Analysis, Elsevier, vol. 51(8), pages 4028-4037, May.

    More about this item


    Purchasing Power Parity (PPP); Panel unit root and cointegration tests; Cross-sectional dependence;

    JEL classification:

    • C23 - Mathematical and Quantitative Methods - - Single Equation Models; Single Variables - - - Models with Panel Data; Spatio-temporal Models
    • F31 - International Economics - - International Finance - - - Foreign Exchange


    Access and download statistics


    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:ihs:ihsesp:159. 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: (Doris Szoncsitz). General contact details of provider: .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.