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Modelling Asymmetric Cointegration and Dynamic Multipliers in a Nonlinear ARDL Framework

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Abstract

We develop a cointegrating nonlinear autoregressive distributed lag (NARDL) model in which short- and long-run nonlinearities are introduced via positive and negative partial sum decompositions of the explanatory variables. We demonstrate that the model is estimable by OLS and that reliable long-run inference can be achieved by bounds-testing regardless of the integration orders of the variables. Furthermore, we derive asymmetric dynamic multipliers that graphically depict the traverse between the short- and the long-run. The salient features of the model are illustrated using the example of the nonlinear unemployment-output relationship in the US, Canada and Japan.

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Notes

  1. 1.

    The present version of the paper is a substantially revised version of Shin and Yu (2004), which has benefited greatly from a sequence of incremental improvements and additions arising from the constructive comments of conference and seminar participants and from editorial feedback. Earlier versions of the paper circulated under the titles “An ARDL Approach to an Analysis of Asymmetric Long-run Cointegrating Relationships” and “Modelling Asymmetric Cointegration and Dynamic Multipliers in an ARDL Framework”. By virtue of its wide circulation and prolonged availability as a working paper, our research has informed the development of a subsequent literature that we now discuss. In all cases, however, the development of the NARDL model is properly credited.

  2. 2.

    The presence of long-run asymmetry will induce a ratchet mechanism if the respective positive and negative regime probabilities are approximately equal and the shocks under each regime are of comparable magnitude. In the more general case in which these conditions are not satisfied, no such simple conclusion may be drawn.

  3. 3.

    Consider the threshold ECM as an example, in which case the choice of the transition variable is of importance both theoretically and empirically. In general, the asymptotic distribution of the test statistic for the null of linearity or symmetry is not only non-standard but also depends on these transition variables.

  4. 4.

    The concept of asymmetric cointegration is easily conceptualised by use of a simple example. Consider the output-unemployment relationship. In a standard cointegrating regression, one models y t and x t subject to a common stochastic trend. As this relationship is assumed to hold in the long-run, it represents the equilibrium to which the system returns after a perturbation (i.e. it acts as a global attractor). However, in our framework, the long-run relationship between y t and x t is modelled as piecewise linear subject to the decomposition of x t . Suppose that \({\vert \beta }^{+}\vert < {\vert \beta }^{-}\vert \) in (9.1). This suggests that the long-run effect of a unit negative change in output will increase unemployment by a greater amount than a unit positive change would reduce it. Thus, our model includes a regime-switching cointegrating relationship in which regime transitions are governed by the sign of \(\Delta x_{t}\). The economic implication of this line of reasoning is that equilibrium need not be unique in a globally linear sense. The link to the path dependency literature is apparent.

  5. 5.

    In the special case where v t is normally distributed with zero mean and constant variance \(\sigma _{v}^{2}\), it is well-established that the censored normal variates, \(v_{t}^{+} =\max \left [0,v_{t}\right ]\) and \(v_{t}^{-} =\min \left [0,v_{t}\right ]\), will have \(E\left (v_{t}^{+}\right ) = \frac{\sigma _{v}} {\sqrt{2\pi }}\), \(E\left (v_{t}^{-}\right ) = - \frac{\sigma _{v}} {\sqrt{2\pi }}\), and \(V ar\left (v_{t}^{+}\right ) = V ar\left (v_{t}^{-}\right ) = \frac{\sigma _{v}^{2}} {2} \frac{\pi -1} {\pi }\). We are grateful to Jinseo Cho for pointing this issue out and encouraging us to provide a more general result in Theorem 1.

  6. 6.

    Notice that the analysis of short-run dynamic asymmetries is not straightforward in the context of the static regression model employing the semiparametric approach.

  7. 7.

    In some cases, most notably where the growth rates of the series in \(\boldsymbol{x}_{t}\) are predominantly positive (negative), the use of a zero threshold may result in one regime containing an undesirably low number of effective observations. In such situations, an obvious candidate for an alternative threshold is the mean growth rate. We discuss such issues further in a separate paper (Greenwood-Nimmo et al. 2012).

  8. 8.

    For convenience we employ the same lag order, q. One may also allow for feedback effects from the lagged \(\Delta y\)’s on \(\Delta x_{t}\) in (9.8).

  9. 9.

    While the associated critical values can be tabulated easily using stochastic simulation, it is impractical to provide a meaningful set of critical values covering all possible combinations. It is generally straightforward, however, to compute the appropriate p-values by means of standard bootstrap techniques.

  10. 10.

    It is straightforward to extend similar reasoning to the more general case with multiple regressors decomposed into partial sum processes.

  11. 11.

    The level parameters are obtained as follows:

    $$\displaystyle{ \phi _{1} =\rho +1 +\varphi _{1};\ \phi _{i} =\varphi _{i} -\varphi _{i-1},\ i = 2,\ldots,p - 1;\ \phi _{p} = -\varphi _{p-1}; }$$
    $$\displaystyle{ \boldsymbol{\theta }_{0}^{\ell} =\boldsymbol{\pi }_{ 0}^{\ell};\ \boldsymbol{\theta }_{ 1}^{\ell} {=\boldsymbol{\theta } }^{\ell} -\boldsymbol{\pi }_{ 0}^{\ell} +\boldsymbol{\pi }_{ 1}^{\ell};\ \boldsymbol{\theta }_{ i}^{\ell} =\boldsymbol{\pi }_{ i}^{\ell} -\boldsymbol{\pi }_{ i-1}^{\ell},\ i = 2,\ldots,q - 1;\ \boldsymbol{\theta }_{ q}^{\ell} = -\boldsymbol{\pi }_{ q-1}^{\ell},\ \ell = +,-. }$$
  12. 12.

    The dynamic multipliers, \(\boldsymbol{\lambda }_{j}^{+}\) and \(\boldsymbol{\lambda }_{j}^{-}\) for j = 0, 1, , can be evaluated using the following recursive relationships in which \(\boldsymbol{\lambda }_{0}^{\ell} =\boldsymbol{\theta }_{ 0}^{\ell}\), ϕ j  = 0 for j < 1 and \(\boldsymbol{\lambda }_{j}^{\ell} =\boldsymbol{ 0}\) for j < 0:

    $$\displaystyle{ \boldsymbol{\lambda }_{j}^{\ell} =\phi _{ 1}\boldsymbol{\lambda }_{j-1}^{\ell} +\phi _{ 2}\boldsymbol{\lambda }_{j-2}^{\ell} +\ldots +\phi _{ j-1}\boldsymbol{\lambda }_{1}^{\ell} +\phi _{ j}\boldsymbol{\lambda }_{0}^{\ell} +\boldsymbol{\theta }_{ j}^{\ell},\ \ell = +,-,\ j = 1, 2,\ldots, }$$
  13. 13.

    The final specification in Borenstein et al. (1997) differs slightly from (9.14) as the lagged \(\Delta y_{t}\)’s on the right hand side are also decomposed into positive and negative changes. However, their derivation is rather ad hoc.

  14. 14.

    Short-run symmetry restrictions (especially the pair-wise restrictions) may be excessively restrictive in many applications although they may be useful in providing more precise estimation results, particularly when estimating a long-run asymmetric relationship in small samples. The additive symmetry restrictions are somewhat weaker and have been discussed in the literature in terms of assessing the validity of the liquidity constraint where \(\sum _{i=0}^{q-1}\boldsymbol{\pi }_{i}^{+} <\sum _{ i=0}^{q-1}\boldsymbol{\pi }_{i}^{-}\) (e.g. Van Treeck 2008).

  15. 15.

    Webber (2000) utilises a similar approach in his analysis of the asymmetric pass-through from exchange rates, decomposed as the partial sum processes of appreciations and depreciations, to import prices.

  16. 16.

    Full results are available on request.

  17. 17.

    We employ a non-parametric bootstrapping routine and use 50,000 replications after rejecting those for which \(\rho > -1 \times 1{0}^{-4}\). Full details are available on request.

  18. 18.

    Earlier drafts of the paper include an additional illustration which has subsequently been removed to conserve space. Previously, the NARDL model was used to investigate to the so-called ‘rockets-and-feathers’ hypothesis associated with Bacon (1991), which describes how retail gasoline prices tend to react asymmetrically to changes in the price of crude oil (an exhaustive survey is provided by Grasso and Manera 2007). Working with Korean data spanning the period 1991q1–2007q2, our results confirm that gasoline prices respond more rapidly to increases in the price of crude oil than to decreases. Furthermore, our results suggest that the gasoline price is more sensitive to exchange rate depreciations than to appreciations and that gasoline price adjustments are approximately symmetric in the long-run. A complete discussion is available from the authors on request.

  19. 19.

    Further examples of the use of positive/negative decompositions in the modelling of asymmetry in the unemployment-output relationship include Lee (2000) and Virén (2001).

  20. 20.

    Seasonally-adjusted monthly data for unemployment and industrial production covering the range 1982m2–2003m11 were collected from the OECD’s Main Economic Indicators. Although not presented here, ADF testing lends overwhelming support to the hypothesis that all variates are I(1).

References

  • Altissimo F, Violante G (2001) The nonlinear dynamics of output and unemployment in the U.S.J Appl Econom 16:461–486

    Google Scholar 

  • Apergis N, Miller S (2006) Consumption asymmetry and the stock market: empirical evidence. Econ Lett 93:337–342

    Article  Google Scholar 

  • Attfield CLF, Silverstone B (1998) Okun’s law, cointegration and gap variables. J Macroecon 20: 625-637

    Article  Google Scholar 

  • Bachmeier LJ, Griffin JM (2003) New evidence on asymmetric gasoline price responses. Rev Econ Stat 85:772–776

    Article  Google Scholar 

  • Bacon RW (1991) Rockets and feathers: the asymmetric speed of adjustment of UK retail gasoline prices to cost changes. Energy Econ 13:211–218

    Article  Google Scholar 

  • Bae Y, de Jong RM (2007) Money demand function estimation by nonlinear cointegration. J Appl Econom 22:767–793

    Article  Google Scholar 

  • Balke NS, Fomby TB (1997) Threshold cointegration. Int Econ Rev 38:627–645

    Article  Google Scholar 

  • Banerjee A, Dolado J, Mestre R (1998) Error-correction mechanism tests for cointegration in a single-equation framework. J Time Ser Anal 19:267–283

    Article  Google Scholar 

  • Blanchard OJ, Summers LH (1987) Hysteresis and the European unemployment problem. Working paper no. 1950, NBER, Cambridge

    Google Scholar 

  • Borenstein S, Cameron C, Gilbert R (1997) Do gasoline prices respond asymmetrically to crude oil price changes? Q J Econ 112:305–339

    Article  Google Scholar 

  • Crespo Cuaresma J (2003) Okun’s law revisited. Oxf Bull Econ Stat 65:439–451

    Article  Google Scholar 

  • Delatte AL, Lopez-Villavicencio A (2012) Asymmetric exchange rate pass-through: Evidence from major countries. J Macroecon 34:833–844

    Article  Google Scholar 

  • Dickey DA, Fuller WA (1979) Distribution of the estimators for autoregressive time series with a unit root. J Am Stat Assoc 74:427–431

    Google Scholar 

  • Engle RF, Granger CWJ (1987) Co-integration and error correction: representation, estimation and testing. Econometrica 55:251–276

    Article  Google Scholar 

  • Escribano A, Sipols AE, Aparicio FM (2006) Nonlinear cointegration and nonlinear error correction: record counting cointegration tests. Commun Stat Simul Comput 35:939–956

    Article  Google Scholar 

  • Granger CWJ, Yoon G (2002) Hidden cointegration. University of California, Mimeo, San Diego

    Google Scholar 

  • Grasso M, Manera M (2007) Asymmetric error correction models for the oil-gasoline price relationship. Energy Policy 35:156–177

    Article  Google Scholar 

  • Greenwood-Nimmo MJ, Shin Y, Van Treeck T, Yu B (2013) The great moderation and the decoupling of monetary policy from long-term rates in the U.S. during the Great Moderation. University of Melbourne, Mimeo

    Google Scholar 

  • Greenwood-Nimmo MJ, Shin Y, Van Treeck T (2012) The nonlinear ARDL model with multiple unknown threshold decompositions: An application to the Phillips curve in Canada. University of Melbourne, Mimeo

    Google Scholar 

  • Hamanda K, Kurosaka Y (1984) The relationship between production and unemployment in Japan: Okun’s Law in a comparative perspective. Eur Econ Rev 25:71–94

    Article  Google Scholar 

  • Hamilton JD (1994) Time series analysis. Princeton University Press, Princeton

    Google Scholar 

  • Hamermesh DS, Pfann GA (1996) Adjustment costs in factor demand. J Econ Lit 34:1264–1292

    Google Scholar 

  • Hansen BE (1995) Rethinking the univariate approach to unit root tests: how to use covariates to increase power. Econom Theory 11:1148–1171

    Article  Google Scholar 

  • Hansen BE (2000) Sample splitting and threshold estimation. Econometrica 68:575–603

    Article  Google Scholar 

  • Johansen S (1988) Statistical analysis of cointegration vectors. J Econ Dyn Control 12:231–254

    Article  Google Scholar 

  • Kahneman D, Tversky A (1979) Prospect theory: an analysis of decisions under risk. Econometrica 47:263–291

    Article  Google Scholar 

  • Kapetanios G, Shin Y, Snell A (2006) Testing for cointegration in nonlinear smooth transition error correction models. Econom Theory 22:279–303

    Article  Google Scholar 

  • Keynes JM (1936) The general theory of employment, interest and money. Macmillan, London

    Google Scholar 

  • Kremers JJM, Ericsson KR, Dolado JJ (1992) The power of cointegration tests. Oxf Bull Econ Stat 54:325–348

    Article  Google Scholar 

  • Kwiatkowski D, Phillips PCB, Schmidt P, Shin Y (1992) Testing the null hypothesis of stationarity against the alternative of a unit root. J Econom 54:159–178

    Article  Google Scholar 

  • Lang D, de Peretti C (2009) A strong hysteretic model for Okun’s law: theory and preliminary investigation. Int Rev Appl Econ 23:445–462

    Article  Google Scholar 

  • Lardic S, Mignon V (2008) Oil prices and economic activity: an asymmetric cointegration approach. Energy Econ 30:847–855

    Article  Google Scholar 

  • Lee J (2000) The robustness of Okun’s Law: evidence from OECD countries. J Macroecon 22: 331–56

    Article  Google Scholar 

  • Neftci SN (1984) Are economic time series asymmetric over the business cycle? J Pol Econ 92:307–328

    Article  Google Scholar 

  • Nguyen VH, Shin Y (2010) Asymmetric price impacts of order flow on exchange rate dynamics. Leeds University Business School, Mimeo

    Google Scholar 

  • Park JY, Phillips PCB (2001) Nonlinear regressions with integrated time series. Econometrica 69:117–161

    Article  Google Scholar 

  • Pesaran MH, Shin Y (1998) An autoregressive distributed lag modelling approach to cointegration analysis. In: Strom S (ed) Econometrics and economic theory: the Ragnar Frisch centennial symposium. Cambridge University Press, Cambridge

    Google Scholar 

  • Pesaran MH, Shin Y, Smith RJ (1999) Pooled mean group estimation of dynamic heterogenous panels. J Am Stat Assoc 94:621–634

    Article  Google Scholar 

  • Pesaran MH, Shin Y, Smith RJ (2001) Bounds testing approaches to the analysis of level relationships. J Appl Econom 16:289–326

    Article  Google Scholar 

  • Phillips PCB, Hansen B (1990) Statistical inference in instrumental variables regression with I(1) processes. Rev Econ Stud 57:99–125

    Article  Google Scholar 

  • Psaradakis Z, Sola M, Spagnolo F (2004) On Markov error-correction models with an application to stock prices and dividends. J Appl Econom 19:69–88

    Article  Google Scholar 

  • Saikkonen P (1991) Asymptotically efficient estimation of cointegrating regressions. Econom Theory 7:1–21

    Article  Google Scholar 

  • Saikkonen P (2008) Stability of regime switching error correction models under linear cointegration. Econom Theory 24:294–318

    Article  Google Scholar 

  • Saikkonen P, Choi I (2004) Cointegrating smooth transition regressions. Econom Theory 20:301–340

    Article  Google Scholar 

  • Schorderet Y (2001) Revisiting Okun’s law: an hysteretic perspective. University of California, Mimeo, San Diego

    Google Scholar 

  • Schorderet Y (2003) Asymmetric cointegration. University of Geneva, Mimeo

    Google Scholar 

  • Shiller RJ (1993) Macro markets: creating institutions for managing society’s largest economic risks. Clarendon Press, Oxford

    Google Scholar 

  • Shiller RJ (2005) Irrational exuberance, 2nd edn. Princeton University Press, Princeton

    Google Scholar 

  • Shin Y, Yu B (2004) An ARDL approach to an analysis of asymmetric long-run cointegrating relationships. Leeds University Business School, Mimeo

    Google Scholar 

  • Shirvani H, Wilbratte B (2000) Does consumption respond more strongly to stock market declines than to increase? Int Econ J 14:41–49

    Google Scholar 

  • Tanaka Y (2001) Employment tenure, job expectancy and earnings profile in Japan. Appl Econ 33:365–374

    Article  Google Scholar 

  • Van Treeck T (2008) Asymmetric income and wealth effects in a non-linear error correction model of US consumer spending. Working paper no. 6/2008, Macroeconomic Policy Institute in the Hans-Böckler Foundation, Düsseldorf

    Google Scholar 

  • Virén M (2001) The Okun curve is non-linear. Econ Lett 70:253–57

    Article  Google Scholar 

  • Webber AG (2000) Newton’s gravity law and import prices in the Asia Pacific. Jpn World Econ 12:71–87

    Article  Google Scholar 

Download references

Acknowledgements

This is a substantially revised version of an earlier working paper by Shin and Yu (2004). Earlier versions circulated under the titles “An ARDL Approach to an Analysis of Asymmetric Long-Run Cointegrating Relationships” and “Modelling Asymmetric Cointegration and Dynamic Multipliers in an ARDL Framework”. We are grateful to Badi Baltagi, Jinseo Cho, Ana-Maria Fuertes, Liang Hu, John Hunter, Minjoo Kim, Soyoung Kim, Gary Koop, Kevin Lee, Camilla Mastromarco, Emi Mise, Viet Nguyen, Neville Norman, Hashem Pesaran, Kevin Reilly, Laura Serlenga, Ron Smith, Till van Treeck and participants at the ESEM conference (Vienna 2006), the ICAETE conference (Hyderabad 2009), and research seminars at the IMK, the Bank of Korea, and the Universities of Bari, Lecce, Leeds, Leicester, Korea and Yonsei for their helpful comments. This paper has been widely circulated and the methodology adopted by a number of authors – we are pleased to acknowledge their valuable feedback, comments and discussion. Shin acknowledges partial financial support from the ESRC (Grant No. RES-000-22-3161). Yu is grateful for the hospitality of Leeds University Business School during his visit. The usual disclaimer applies.

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Appendix

Appendix

9.1.1 Proof of Theorem 1

The OLS estimator, \(\hat{\boldsymbol{\beta }}:= {{(\hat{\beta }}^{+}{,\hat{\beta }}^{-})}^{{\prime}}\), in (9.1) is obtained by

$$\displaystyle{ \hat{\boldsymbol{\beta }}={ \left [\begin{array}{cc} \sum _{t=1}^{T}{\left (x_{t}^{+}\right )}^{2} & \sum _{t=1}^{T}x_{t}^{+}x_{t}^{-} \\ \sum _{t=1}^{T}x_{t}^{+}x_{t}^{-}& \sum _{t=1}^{T}{\left (x_{t}^{-}\right )}^{2} \end{array} \right ]}^{-1}\left [\begin{array}{c} \begin{array}{c} \sum _{t=1}^{T}x_{ t}^{+}y_{ t} \\ \sum _{t=1}^{T}x_{t}^{-}y_{t} \end{array} \end{array} \right ], }$$

so that

$$\displaystyle{ \hat{\boldsymbol{\beta }}-\boldsymbol{\beta } = \frac{1} {D_{T}}\left [\begin{array}{cc} \sum _{t=1}^{T}{\left (x_{t}^{-}\right )}^{2} & -\sum _{t=1}^{T}x_{t}^{+}x_{t}^{-} \\ -\sum _{t=1}^{T}x_{t}^{+}x_{t}^{-}& \sum _{t=1}^{T}{\left (x_{t}^{+}\right )}^{2} \end{array} \right ]\left [\begin{array}{c} \begin{array}{c} \sum _{t=1}^{T}x_{t}^{+}u_{t} \\ \sum _{t=1}^{T}x_{t}^{-}u_{t} \end{array} \end{array} \right ] = \frac{1} {D_{T}}\left [\begin{array}{c} A_{T} \\ B_{T} \end{array} \right ], }$$

where \(D_{T}:=\sum _{ t=1}^{T}{\left (x_{t}^{+}\right )}^{2}\sum _{t=1}^{T}{\left (x_{t}^{-}\right )}^{2} -{\left (\sum _{t=1}^{T}x_{t}^{+}x_{t}^{-}\right )}^{2}\), \(A_{T}:=\sum _{ t=1}^{T}{\left (x_{t}^{-}\right )}^{2}\) \(\sum _{t=1}^{T}x_{t}^{+}u_{t} -\sum _{t=1}^{T}x_{t}^{+}x_{t}^{-}\sum _{t=1}^{T}x_{t}^{-}u_{t}\), and \(B_{T}:= -\sum _{t=1}^{T}x_{t}^{+}x_{t}^{-}\sum _{t=1}^{T}x_{t}^{+}u_{t} +\sum _{ t=1}^{T}{\left (x_{t}^{+}\right )}^{2}\sum _{t=1}^{T}x_{t}^{-}u_{t}\). We now let

$$\displaystyle{ w_{t}^{+}:=\max [0,v_{ t}] {-\mu }^{+},\;\;\;\;w_{ t}^{-}:=\min [0,v_{ t}] {-\mu }^{-}, }$$

where \({\mu }^{+}:= E\left [\max [0,v_{t}]\right ]\) and \({\mu }^{-}:= E\left [\min [0,v_{t}]\right ]\), so that

$$\displaystyle{ x_{t}^{+} \equiv {t\mu }^{+} +\sum _{ j=1}^{t}w_{ j}^{+},\;\;\;\;x_{ t}^{-}\equiv {t\mu }^{-} +\sum _{ j=1}^{t}w_{ j}^{-} }$$

Hence, we obtain:

$$\displaystyle\begin{array}{rcl} D_{T}& =& \left \{\sum _{t=1}^{T}{t}^{2}\right \}\left \{\sum _{ t=1}^{T}\left [{\mu }^{+2}{\left (\sum _{ j=1}^{t}w_{ j}^{-}\right )}^{2} {+\mu }^{-2}{\left (\sum _{ j=1}^{t}w_{ j}^{+}\right )}^{2}\right.\right. {}\\ & & -\,{2\mu }^{+}\left.\left.{\mu }^{-}\left (\sum _{ j=1}^{t}w_{ j}^{-}\right )\left (\sum _{ j=1}^{t}w_{ j}^{+}\right )\right ]\right \} {}\\ & & -\left \{{\mu }^{+2}{\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{-}\right )}^{2}\right. {}\\ & & +\,\left.{\mu }^{-2}{\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{+}\right )}^{2} - {2\mu {}^{+}\mu }^{-}\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{-}\right )\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{+}\right )\right \} {}\\ & & +\,o_{P}({T}^{5}). {}\\ \end{array}$$

Here, o P (T 6) terms are canceled off, and the remaining next-order terms are stated as above. We now note that

$$\displaystyle{ \frac{1} {{T}^{3}}\sum\limits_{t=1}^{T}{t}^{2} = \frac{1} {3} + o(1), }$$
$$\displaystyle{{ \mu }^{+2}{\left (\sum _{ j=1}^{t}w_{ j}^{-}\right )}^{2} {+\mu }^{-2}{\left (\sum _{ j=1}^{t}w_{ j}^{+}\right )}^{2} - {2\mu {}^{+}\mu }^{-}\left (\sum _{ j=1}^{t}w_{ j}^{-}\right )\left (\sum _{ j=1}^{t}w_{ j}^{+}\right ) ={ \left (\sum _{ j=1}^{t}s_{ j}\right )}^{2} }$$

where \(s_{j} {\equiv \mu }^{+}w_{j}^{-}{-\mu }^{-}w_{j}^{-}\) by the definitions of \(w_{j}^{-}\) and \(w_{j}^{+}\). Hence, by Donsker’s FCLT

$$\displaystyle{ {T}^{-1/2}\sum\limits_{ j=1}^{T(\cdot )}s_{ t}/\sigma _{s} \Rightarrow W_{\tilde{s}}(\cdot ), }$$

where \(\sigma _{s}^{2}:= V ar\left (s_{t}\right )\), ⇒ indicates weak convergence, and \(W_{\tilde{s}}(r)\) is the standard Brownian motions defined on \(r \in \left [0,1\right ]\). Therefore,

$$\displaystyle{ {T}^{-2}\sum\limits_{ t=1}^{T}{\left (\sum\limits_{ j=1}^{t}s_{ j}\right )}^{2} \Rightarrow \sigma _{ s}^{2}\int _{ 0}^{1}W_{\tilde{ s}}{(r)}^{2}dr }$$

by the CMT (e.g. Eq. (17.3.22) of Hamilton (1994), p. 486). Also notice that

$$\displaystyle\begin{array}{rcl} & & {\mu }^{+2}{\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{-}\right )}^{2} {+\mu }^{-2}{\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{+}\right )}^{2} {}\\ & & \quad - {2\mu {}^{+}\mu }^{-}\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{-}\right )\left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}w_{ j}^{+}\right ) {}\\ & =&{ \left (\sum _{t=1}^{T}t\sum _{ j=1}^{t}\left ({\mu }^{+}w_{ j}^{-}{-\mu }^{-}w_{ j}^{+}\right )\right )}^{2} ={ \left (\sum _{ t=1}^{T}t\sum _{ j=1}^{t}s_{ j}\right )}^{2}, {}\\ \end{array}$$

then it follows that

$$\displaystyle{ {T}^{-\frac{5} {2} }\sum\limits_{t=1}^{T}t\sum\limits_{j=1}^{t}s_{j} \Rightarrow \sigma _{s}\int _{0}^{1}rW_{\tilde{s}}(r)dr }$$

by the CMT. Collecting all these results we obtain:

$$\displaystyle{ {T}^{-5}D_{ T} \Rightarrow \sigma _{s}^{2}\left [\frac{1} {3}\int _{0}^{1}W_{\tilde{ s}}{(r)}^{2}dr -{\left (\int _{ 0}^{1}rW_{\tilde{ s}}(r)dr\right )}^{2}\right ]. }$$
(9.25)

Next, we consider the asymptotic weak limit of the numerator of \({\hat{\beta }}^{+} {-\beta }^{+}\). For this, we note that the O P (T 9∕2) terms cancel off and that the remaining next-order terms are O p (T 4) so that

$$\displaystyle\begin{array}{rcl} A_{T}&:=& \sum _{t=1}^{T}{\left (x_{ t}^{-}\right )}^{2}\sum _{ t=1}^{T}x_{ t}^{+}u_{ t} -\sum _{t=1}^{T}x_{ t}^{+}x_{ t}^{-}\sum _{ t=1}^{T}x_{ t}^{-}u_{ t} \\ & =& \left \{{\mu }^{-2}\sum _{ t=1}^{T}{t}^{2}\sum _{ t=1}^{T}u_{ t}\sum _{j=1}^{t}w_{ j}^{+} + {2\mu {}^{-}\mu }^{+}\sum _{ t=1}^{T}tu_{ t}\sum _{t=1}^{T}\sum _{ j=1}^{t}w_{ j}^{-}\right \} \\ & &-\left \{{\mu {}^{+}\mu }^{-}\sum _{ t=1}^{T}{t}^{2}\sum _{ t=1}^{T}u_{ t}\sum _{j=1}^{t}w_{ j}^{+} +\sum _{ t=1}^{T}t\sum _{ j=1}^{t}{{(\mu }^{+}w_{ j}^{-} {+\mu }^{-}w_{ j}^{+})\mu }^{-}\sum _{ t=1}^{T}tu_{ t}\right \} \\ & & \quad + o_{P}({T}^{4}) \\ & =& {\mu }^{-}\left \{-\left (\sum _{ t=1}^{T}{t}^{2}\right )\left (\sum _{ t=1}^{T}u_{ t}\sum _{j=1}^{t}s_{ j}\right ) + \left (\sum _{t=1}^{T}t\sum _{ j=1}^{t}s_{ j}\right )\left (\sum _{t=1}^{T}tu_{ t}\right )\right \} + o_{P}({T}^{4}){}\end{array}$$
(9.26)

where we also employ the definition of \(s_{j}:{=\mu }^{+}w_{j}^{-}{-\mu }^{-}w_{j}^{+}\). Then, by the CMT (e.g. Eqs. (f) on p. 548 and (17.3.19) on p. 486 of Hamilton (1994), respectively) we have:

$$\displaystyle{ {T}^{-1}\sum\limits_{ t=1}^{T}u_{ t}\sum\limits_{j=1}^{t}s_{ j} \Rightarrow \sigma _{s}\sigma _{u}\int _{0}^{1}W_{\tilde{ s}}(r)dW_{\tilde{u}}(r) }$$
(9.27)
$$\displaystyle{ {T}^{-\frac{3} {2} }\sum _{t=1}^{T}tu_{t} \Rightarrow \sigma _{u}\left (W_{\tilde{u}}(1) -\int _{0}^{1}W_{\tilde{u}}(r)dr\right ) }$$
(9.28)

where \(W_{\tilde{u}}(\cdot )\) is a standard Brownian motion independent of \(W_{\tilde{s}}(\cdot )\). Collecting all these results and (9.28) and plugging them into A T , we obtain by the CMT:

$$\displaystyle\begin{array}{rcl}{ T}^{-4}A_{ T}& \Rightarrow & {\mu }^{-}\sigma _{ s}\sigma _{u} \\ & & \times \left \{-\frac{1} {3}\int _{0}^{1}W_{\tilde{ s}}(r)dW_{\tilde{u}}(r) +\int _{ 0}^{1}rW_{\tilde{ s}}(r)dr\left (W_{\tilde{u}}(1) -\int _{0}^{1}W_{\tilde{ u}}(r)dr\right )\right \} \\ & & {}\end{array}$$
(9.29)

We now examine the numerator of \({(\hat{\beta }}^{-}{-\beta }^{-})\) in a similar manner. That is,

$$\displaystyle{ B_{T}:{=\mu }^{+}\sigma _{ s}\sigma _{u}\left \{\left (\sum\limits_{t=1}^{T}{t}^{2}\right )\left (\sum\limits_{ t=1}^{T}u_{ t}\sum\limits_{j=1}^{t}s_{ j}\right ) -\left (\sum\limits_{t=1}^{T}t\sum\limits_{ j=1}^{t}s_{ j}\right )\left (\sum\limits_{t=1}^{T}tu_{ t}\right )\right \} + o_{P}({T}^{4}),\qquad }$$
(9.30)

and

$$\displaystyle\begin{array}{rcl}{ T}^{-4}B_{ T}{\Rightarrow \mu }^{+}\sigma _{ s}\sigma _{u}\left \{\frac{1} {3}\int _{0}^{1}W_{\tilde{ s}}(r)dW_{\tilde{u}}(r)-\int _{0}^{1}rW_{\tilde{ s}}(r)dr\left (W_{\tilde{u}}(1)-\int _{0}^{1}W_{\tilde{ u}}(r)dr\right )\right \}& & \\ & &{}\end{array}$$
(9.31)

Combining (9.29) and (9.31) respectively with (9.25) we obtain the main results.

Next, from (9.26) and (9.30), it is easily seen that

$$\displaystyle{{ \mu }^{+}A_{ T} {+\mu }^{-}B_{ T} = o_{P}({T}^{4}), }$$

which proves the final result in Theorem 1.

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Shin, Y., Yu, B., Greenwood-Nimmo, M. (2014). Modelling Asymmetric Cointegration and Dynamic Multipliers in a Nonlinear ARDL Framework. In: Sickles, R., Horrace, W. (eds) Festschrift in Honor of Peter Schmidt. Springer, New York, NY. https://doi.org/10.1007/978-1-4899-8008-3_9

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