Sources of economic fluctuations in France: A structural VAR model European Journal of Government and Economics Volume 1, Number 1 (June 2012) ISSN: 2254-7088 66 Sources of economic fluctuations in France: A structural VAR model Nabil Ben-Arfa, University of Nice Sophia Antipolis, France* Abstract This paper studies the economic fluctuations of an open economy such as the French economy. A system of variables containing output, price level, trade balance, real exchange rate and oil prices is analyzed by applying the structural vector autoregressive (SVAR) methodology initiated by Sims (1980). This set of variables allows to evaluate the main sources of impulses of the French economy fluctuations. The results show that five structural shocks are identified using the long-run constraints implemented by Blanchard and Quah (1989). From the SVAR dynamic properties, impulse response functions and variance decomposition, the French economy is shown to be particularly vulnerable to supply and oil price shocks, where these two shocks respectively contribute to 40% and 35% of the economic disturbance. France is also hit by important external shocks which damage its trade balance position. Finally, it is found that shocks related to economic policy (demand shocks) have a quite limited impact on the economic activity. JEL Classification E32; F41; C22 Keywords economic fluctuations; external shocks; internal shocks; oil price shock; SVAR model * Address for correspondence: Nabil Ben Arfa, CEMAFI, University of Nice Sophia-Antipolis, Résidence les Imperators, immeuble le Constantin A, Chemin de la Lauve, 83700 Saint Raphaël, France. E-mail : nabil_ar@yahoo.fr. DOI: https://doi.org/10.17979/ejge.2012.1.1.4277 European Journal of Government and Economics 1(1) 67 Introduction The 1980s have operated a methodological and a theoretical revival on the economic fluctuations analysis. The aim of this paper is to deal with empirical treatment of economic disturbances. Sims (1980) was the pioneer of the fluctuations analysis within the vectorial autoregressive model, where impulses are apprehended as innovations in a statistical term. These VAR models were introduced as an alternative to the traditional econometric models. Sims proposed a new form of modeling based on no a priori and where no distinction is made between exogenous and endogenous variables. Since pioneer work of Sims (1980), the main empirical work dealing with the sources of economic fluctuations lay on autoregressive vectorial model. These canonical VAR models however posed some problems related to the shocks identification, they faced a lot of criticisms, qualifying them as “atheoretical” models. These criticisms lead to the birth of structural VAR models, models in which shocks identification is conducted by the imposition of constraints drawn from economic theory. It is this methodology of structural VAR which will be applied to the French economy. We will apply a structural VAR model to the French economy in order to identify the main shocks which are the origin of the economic activity fluctuations. In the second section we will reconsider the theoretical and the methodological revival of fluctuations analysis. In the third and the fourth part of the paper we explore the data used and estimate the structural VAR model. Finally, we interpret the results. The methodological and theoretical revival of the fluctuation analysis: The 1980s has operated a methodological and a theoretical revival on the analysis of economic fluctuations. The methodological revival was initiated by Sims (1980); it was inscribed on the line of the impulse-propagation approach suggested by Frisch (1933) and Slutsky (1927). On a theoretical level, real business cycle theory constitutes a true theoretical revival on the fluctuations analysis: it proposes to explain the main part of the economic fluctuations within the neo-classic growth model disturbed only by shocks affecting the total factor productivity. This marks the abandonment of the debate on the relative importance of monetary versus fiscal shocks. The debate on the relative importance of supply and demand shocks emerges. Real Business cycle theory At the beginning of the eighties, the relevance of the equilibrium monetary theory was rejected in a theoretical as in an empirical level. It is in this context that appears the real business cycles theory, or RBC1, with the pioneers’ models of Kydland and Prescott (1982) and Long and Plosser (1983) in closed economy. The real business cycle theory considers economic fluctuations as the optimal response of economic agents to shocks on the total factor productivity. The models of real business cycle thus conceive the evolution of economic aggregates as the decision result of a great number of agents seeking to maximize their utility and only constrained by technological resource. The real business cycle theory attributes an insignificant role, even no role, to the monetary policy 1 For Real Business Cycles. European Journal of Government and Economics 1(1) 68 These basic models were followed by many extensions: extensions to open economies, with the international real business cycle of Backus, Kehoe and Kydland (1992, 1994, and 1995). Extensions to others shock in addition to the technological shock, by borrowing theoretical assumptions from the Keynesian theory. Criticisms addressed to the basic real business cycle models lead to the development of an abundant literature, with increasingly sophisticated models. Results of these developments were not always satisfactory especially concerning the reproduction of the stylized facts. The methodological contribution of the real business cycles theory is however admitted by a large part of economists. Parallel to this movement within the real business cycle theory, a new school of thought was emerging; it is the new Keynesian macroeconomics. The New Keynesian (NK) shares with the partisans of the real business cycle theory the fact that macroeconomic requires more microeconomic bases. However, NK economists believe that market imperfections are the key to understanding the real-world. The introduction of NK ideas into RBC models seems to make results definitely more satisfactory, in the sense that these models are accepted by economics profession and that their empirical results are more realistic. The introduction of the prices rigidity was sufficient to join again with the monetary policy, neutral and without effect in basic RBC models. Some economists saw in this “marriage” between RBC and Keynesian, the birth of “the New Neo-classical Synthesis” (Goodfriend and King 1997). Nowadays, macroeconomic models incorporate the principal theoretical elements of RBC models. They adopt their general structure; seek to identify the impulses response function of agent in a general equilibrium structure. On the other hand, the way in which the models define and identify the cycles is substantially different from the original contributions, various types of imperfections and rigidities are introduced. These imperfections proposed by New Keynesian are related to the imperfect nature of competition on goods market, the specificity of financial market exchange, etc. During last decades, RBC initials disappeared gradually and those of DSGE appear (dynamic stochastic general equilibrium). The methodological revival: VAR model Sims (1980) proposed a tool for fluctuations analysis based on impulses, defined as statistical innovations. Since Sims contribution of 1980, the mains empirical work on the economic fluctuations sources lay on autoregressive vectorial methodology. The purpose of Sims consists in evaluating the contribution of various innovations of a system to the dynamics of each variable. To distinguish the impulses response from the propagation mechanisms, he proposes the Choleski method of orthogonalization. Following criticisms and in particular those concerning the impossible interpretation of shocks economically through the Choleski decomposition, many authors suggest to base the orthogonalization of shocks on structural model of innovations, the structural VAR model. Shapiro and Watson (1988), Blanchard and Quah (1989) and Gali (1992), proposed to identify structural impulses, which are interpretable economically: supply shocks, demand, economic policy…Their methods of identification are based on restrictions drawn from the economic theory. From an econometric point of view the structural impulses are estimated as a function of the canonical innovations, obeying to constraints resulting from the economic theory. The imposed restrictions can be of different kind and their economic implications European Journal of Government and Economics 1(1) 69 diametrically opposite. One distinguishes two types of restrictions used in the recent literature: short term restrictions and long run restrictions. The short run constraints relate to the instantaneous answers of variable to shocks. Long run restrictions are related to the long term shocks responses. Those developments make the birth of the structural VAR model, i.e VAR models where it is possible to give economic definition to various shocks. Data characteristics and VAR model estimation The purpose of this section is to analyze the economic disturbances in an open economy, the French economy. Empirical study presented in this section is based on the VAR methodology incited by Sims (1980). These recent developments on time series econometrics are applied to a system of variable including output, prices, trade balance, real exchange rate and oil price. This system of variables makes possible the evaluation of the main source of disturbance in the French economy. So, in an autoregressive vectorial model including these variables, five structural shocks are identified with the help of the Blanchard and Quah (1989) method of decomposition. Long term characteristics of the data Before the model estimation, we must preliminary check the order of integration and test the possible presence of cointegration relationship between variables. We use quarterly data extending from 1978Q1 to 2007Q4:2 - y: GDP logarithm p: logarithm of consumer price index - se : logarithm of trade balance - tc: logarithm of the real effective exchange rate - pp: logarithm of the oil price Tests of stationarity To analyze the long-term properties of the data, we use three different methods: Augmented Dickey-Fuller test (1979), Phillips-Perron test (1988) and Kwiatkowski- Phillips-Schmidt-Shin test (1992). 2 Our Data comes from the INSEE (Institut National de la Statistique et des Etudes Economiques) database and the IFS (International Financial Statistics) from the IMF (International Monetary Fund). - Q for quarter. - All series are seasonally adjusted. The oil price is in US dollars. The real effective exchange rate is computed with ULCs. European Journal of Government and Economics 1(1) 70 Table 1. Unit root tests Augmented Dickey Fuller (ADF) Phillips-Perron (PP) Kwiatkowski-Phillips-Schmidt-Shin (KPSS) Variables Statistics of the test Critical value (5%) Statistics of the test Critical value (5%) Statistics of the test Critical value (5%) GDP 5.63 -1.95 13.17 -1.95 1.30 0.46 ∆ GDP -4.92 -2.89* -7.55 -2.89* 0.05 0.46 Trade balance -0.17 1.95 -0.03 1.95 0.60 0.46 ∆ (trade balance) -5.35 -1.95 -10.60 -1.95 0.19 0.46 Real foreign exchange rate -1.10 -1.95 -1.10 -1.95 1.20 0.46 ∆ (real foreign exchange rate) -9.66 -1.95 -9.66 -1.95 0.07 0.46 CPI -0.05 -1.95 -0.05 -1.95 0.54 0.46 ∆ (CPI) -8.72 -1.95 -8.72 -1.95 0.05 0.46 The oil price 1.05 -1.95 1.01 -1.95 0.87 0.46 ∆ (Of the oil price) -8.57 -1.95 -8.60 -1.95 0.15 0.46 Notes: - * This critical value is relating to the model with constant and without trend. - The character ∆, indicates the first difference of the variable. - All the variables are in logarithm. According to unit root tests, it appears that all the variables of the model are nonstationary; they are integrated of order one. Cointegration relationship To test the possible existence of cointegration between variables, we use the test implemented by Johansen (1991) and Johansen and Juselius (1990).3 So we suppose the vector X of dimension (5×1): X =  pptcsepy ,,,, The general representation of the model in VECM4 form is given by the following expression:  tX = C + ttptpt XXX   11111 ... Where matrices i  (I = 1,…, p) are of size (N×N). The method suggested by Johansen and Juselius is based on two assumptions: on one hand the vector X must be I (1) and in addition the vector of the residual  must be a white noise. The strategy of the test consists in analyzing the rank of 3 The advantage of this method is that it allows for the identification of multiple cointegrating vectors. The Engle-Granger cointegration methodology (Engle and Granger, 1987) is limited to testing only for one cointegrating vector. 4 VECM for Vector Error Correction Model. European Journal of Government and Economics 1(1) 71 the matrix  . If the rank of  is zero then there is no cointegration between the variables. If the rank of the matrix  is r, there exist two matrices of dimension (n×r),  and  as:  =  ' ' is a matrix which contains the r vectors of cointegration.  is a matrix which contains the weights associated to each vector of cointegration. To determine the number of vectors of cointegration r, Johansen proposes two statistics: the trace test and the maximum eigenvalue test. The trace statistic is the following: TR = - T )1log( 1     N qi i The Ho hypothesis is: r ≤ q, i.e. there are at least r vectors of cointegration. This test is equivalent to test the rank of the matrix  since testing the existence of r vectors is equivalent to test the following null assumption: Rg (  ) = r Three cases can be presented: Rg (  ) = 0, this means that r = 0: there is no cointegration, in other words tX is integrated of order 1 but not cointegrated. It is then possible to estimate a VAR model on  tX . Rg (  ) = r, with r