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Structural VAR and Applications
Jean-Paul Renne
Banque de France
ENSTA, 22 January 2010
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Overview of the presentation
1 Vector Auto-Regressions
DefinitionEstimationTests
2 Impulse responsesGeneral conceptApplication to Structural VAR
3 Applications
1 Blanchard and Quah (1989)2 Smets and Tsatsaronis (1997)3 Dedola and Lippi (2005)
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Structural VARVector Auto-Regressions: Short introduction
The VAR are widely used in economic analysis.
While simple and easy to estimate, they make it possible toconveniently capture the dynamics of multivariate systems.
VAR popularity is mainly due to Sims (1980) influential work.
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Structural VARVector Auto-Regressions: Notations
let yt denote an (n 1) vector of random variables. yt follows a pth
order Gaussian VAR if, for all t, we have
yt = c + 1yt1 + . . .pytp + t
where t N(0,).
Consequentlyyt | yt1,yt2, . . . ,yp+1 N(c +1yt1 + . . .pytp,).
Denoting with the matrix
c 1 2 . . . p
and with xt the
vector 1 yt1 yt2 . . . ytp , the log-likelihood is given byL(YT; ) = (Tn/2) log(2) + (T/2) log
1
1
2
T
t=1 yt
xt
1
yt
xt
.
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
The MLE of, denoted with is given by
= Tt=1
ytx
t T
t=1xtx
t1
. (1)
Exercise 1
After having computed the jth rows of , find an easy way to
estimate .
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
Proof of equation (1)Lets rewrite the last term of the log-likelihood
T
t=1yt
xt
1
yt xt =
Tt=1
yt
xt + xt
xt
1yt
xt + xt
xt
=
Tt=1
t + (
)
xt1
t + (
)
xt
where the jth element of the (n 1) vector t is the sample residual forobservation t from an OLS regression of yjt on xt.
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
T
t=1yt
xt
1
yt xt =
Tt=1
t1t + 2
Tt=1
t1( )xt
+
Tt=1
x
t( )1
( )
xt
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
Lets apply the trace operator on the second term (that is a scalar):
T
t=1
t1( )xt = trace
T
t=1
t1( )xt
= trace
Tt=1
1( )xtt
= trace1
( )
Tt=1
xt
t
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
Given that, by construction, the sample residuals are orthogonal to theexplanatory variables, this term is equal to zero.If xt = ( )
xt, we have
Tt=1
yt
xt
1yt
xt
=
T
t=1
t1t +
T
t=1
xt1xt
Since is a positive definite matrix, 1 is as well. Consequently, thesmallest value that the last term can take is obtained when xt = 0,ie when
= .
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Structural VARVector Auto-Regressions: Maximum Likelihood Estimation (MLE)
Assume that we have computed , the MLE of is the matrix that
maximizes L(YT; ,).
Denoting with t the estimated residual yt xt, we have
L(YT; ,) = (Tn/2) log(2) + (T/2) log 1
12
Tt=1
t
1t
.
is a symmetric positive definite matrix. Fortunately, it turns out
that that the unrestricted matrix that maximizes the latter expressionis a symmetric postive definite matrix. Indeed,
()
=
T
2
1
2
T
t=1t
t = =
1
T
T
t=1t
t.
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Structural VARVector Auto-Regressions: Likelihood-Ratio test
The simplicity of the VAR framework and the tractability of its MLEcontribute to convenience of various econometric tests. We illustratethis here with the likelihhod ratio test.
The maximum value achieved by the MLE is
L(YT; ,) = (Tn/2) log(2) + (T/2) log1
1
2
Tt=1
t1
t
.
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Structural VARVector Auto-Regressions: Likelihood-Ratio test
The last term isTt=1
t1t = trace
Tt=1
t1t
= trace Tt=1
1tt
= trace1
Tt=1
tt
= trace1
T
= Tn.
Therefore
L(YT; ,) = (Tn/2) log(2) + (T/2) log1 Tn/2.
which is easy to calculate.
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Structural VARVector Auto-Regressions: Likelihood-Ratio test
For instance, assume that we want to test the null hypothesis that aset of variable follows a VAR(p0) against the alternative specificationof p1 lags (with p1 > p0).
Let us respectively denote with L0 and L1 the maximum log-likelihoodsobtained withp0 and p1 lags. Under the null hypothesis, we have
2
L1 L0
= T
log11
log
10
which asymptotically has a 2
distribution with degrees of freedomequal to the number of restrictions imposed under H0 (compared withH1), ie n
2(p1 p0).
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Structural VARVector Auto-Regressions: Unconditional variance
The unconditional matrix of variance-covariance of yt is
Var(y) = limt
E0((yt yt)(yt yt))
where yt denotes the unconditional mean of y.
Let denote with yt the vector
yt y
t1 . . . y
tp
, we have
y
t =
c0
...0
+
1 2 p1 0 0
0 . . . 0 00 0 1 0
yt1 +
t0
...0
yt = c + yt1 +
t
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Structural VARVector Auto-Regressions: Unconditional variance
It is then easy to get the Wolds decomposition of yt :
yt = c + c + yt2 + t1+ t
= c + t +(c + t1) + . . . +
k(c + tk) + . . .
The ts being iid, we have
Var(y) = +
+ . . . + k
k + . . .
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Structural VARVector Auto-Regressions: Criteria
In a VAR, adding lags quickly consume degrees of freedom. If laglength is p, each of the n equations contains n p coefficients plusthe intercept term.
Adding lengths improve in-sample fit, but is likely to result inover-parameterization and affect the out-of-sample prediction
performance.To select appropriate lag length, some criteria can be used (they haveto be minimized)
AIC = log
+
2
TN
SBIC = log+ log T
TN
where N = n p2 + p.
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Structural VARVector Auto-Regressions: Granger Causality
Granger (1969) developed a method to analyze the causal relationshipamong variables systematically.
The approach consists in determining whether the past values of y1,tcan help to explain the current y2,t.
Let us denote three information sets
I1,t = {y1,t,y1,t1, . . .}
I2,t = {y2,t,y2,t1, . . .}
It = {y1,t,y1,t1, . . .y2,t,y2,t1, . . .} .
We say that y1,t Granger-causes y2,t if
E [y2,t | I2,t1] = E [y2,t | It1] .
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Structural VARVector Auto-Regressions: Unconditional variance
To get the intuition behind the testing procedure, consider thefollowing bivariate VAR(p) process:
y1,t = 10 + pi=111(i)y1,ti +
pi=112(i)y2,ti + u1,t
y2,t = 20 + pi=121(i)y1,ti +
pi=122(i)y2,ti + u2,t.
Then,y1,t does not Granger-cause y2,t if
21(1) = 21(2) = . . . = 21(p) = 0.
Therefore the hypothesis testing isH0 : 21(1) = 21(2) = . . . = 21(p) = 0
HA : 21(1) = 0 or 21(1) = 0 or . . .21(p) = 0.
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Structural VARVector Auto-Regressions: Unconditional variance
Rejection of H0 implies that some of the coefficients on the laggedy1,ts are statistically significant.
This can be tested using the F-test or asymptotic chi-square test.The F-statistic is F = (RSSUSS)/p
USS/(T2p1) (where RSS: restricted residual
sum of squares, USS: unrestriced residual sum of squares)Under H0, the F-statistic is distributed as F(p, T 2p 1)In addition, pF 2(p).
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Structural VARVector Auto-Regressions: Impulse responses
Objective: analyzing the effect of a given shock on the endogenousvariables.
Let us consider a random variable yt that presents the followingWolds decomposition:
yt =k=0
ktk.
The impulse response function of the shock t on yt,yt+1, . . . is givenby the matrices
k.
Formally, the impulse response of the shock t on the variable y isdefined as
yt+kt
= k.
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Structural VARVector Auto-Regressions: Impulse responses
Dynamics of yt,yt+1,yt+2, . . . when t = 1, t+1 = 0, t+2 = 0, . . .
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Structural VARVector Auto-Regressions: Impulse responses
Exercise 2
Consider the process
yt = 1 + 0.9yt1 + t.
Compute the unconditional mean and variance of yt.
Exercise 2
Consider the process
yt = 1 + 0.5yt1 + 0.4yt2 + t.
Draw the impulse response of yt to t (up to yt+3). What is thecumulated impact of a shock (t = 1, t+1 = 0, t+2 = 0, . . .) onyt?
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Structural VARVector Auto-Regressions: Causal mechanisms
Assume that the GDP growth gt is affected by some real shocks ur,tfollowing
gt = 0.3(it1 t) + ur,t
where it denotes the nominal interest rate and t denotes the inflationrate.
Besides, assume that we have
it = 0.9it1 + 1.5t + ump,t
t = 0.9t1 + 0.2gt1 + un,t
where ump,t and un,t are respectively some monetary-policy andcost-push shocks.
The strucural shocks ut are uncorrelated (i.e., the covariance matrix ofut, denoted with u is diagonal) and ut is serially uncorrelated (i.e.Cov(utk, ut) = 0 for any t and k > 0).
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Structural VARVector Auto-Regressions: Causal mechanisms
The structural model reads
gt = 0.3(it1 t) + ur,t
it = 0.9it1 + 1.5t + ump,t
t = 0.9t1 + 0.2gt1 + un,
t.
To get it in a reduced-form, let us substitute t in the right-handsides of the first two equations:
gt = 0.06gt1 0.3it1 + 0.27t1 + 0.3un,
t + ur,
t
it = 0.9it1 + 1.35t1 + 0.3gt1 + ump,t + 1.5un,t
t = 0.9t1 + 0.2gt1 + un,t.
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Structural VARVector Auto-Regressions: Causal mechanisms
Exercise 3
Write the model in matrix form.
Is this economy stationary?
Propose a way of estimating the model.
How to recover the structural shocks ut?
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Structural VARVector Auto-Regressions:Impulse responses
In matrix form
gtitt
=
0.06 0.3 0.270.3 0.9 1.350.2 0 0.9
gt1it1t1
+
g,ti,t,t
with
g,ti,t
,t
=
1 0 0.30 1 1.5
0 0 1
ur,tump,t
un,t
= B
ur,tump,t
un,t
.
With the procedure described above, one only gets an estimate of
where
= Var
g,ti,t
,t
.
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Structural VARVector Auto-Regressions:Impulse responses
Note however that we must have
= BuB
where u is diagonal positive.
In addition, given the structural framework, one knows that B is anupper-triangular matrix.
The Choleshy decomposition can therefore be used to get the Bmatrix.
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Structural VARVector Auto-Regressions:Impulse responses
Whereas the VAR model is able to capture efficiently the interactionsbetween the different variables, it does not allow to reveal theunderlying causal mecanisms since two different causal schemes cancorrespond to the same reduced forms.
By taking into account certain economic relationships, a StructuralVAR model (SVAR) makes it possible to identify structural shockswhile letting play the interactions between the different variables (seeGali, 1992 or Gerlach and Smets 1995).
Formally, let assume that the residuals t are some linear combinations
of the structural shocks ut, that is:
t = But.
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Structural VARVector Auto-Regressions:Impulse responses
How it has been shown previously, a SVAR is based on a structuralmodel that draws from a theoretical framework.
As a starting point, we always have = BuB that provides us with
n(n + 1)/2 restrictions to recover the B matrix.
Consequently, to get the B matrix, one have to impose n(n 1)/2additional restrictions.
There exist two kinds of restrictions that can be easily implemented ina SVAR: short-run and long-run restrictions:
a short-run restriction prevents a structural shock from affecting anendogenous variable contemporaneously;a long-run restriction prevents a structural shock from affecting anendogenous variable in a cumulative way.
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Structural VARVector Auto-Regressions:Impulse responses
Concretely, the short-run restrictions consists in setting to zero some
entries of B.
The long-run restrictions require additional computations to beapplied. More precisely, one needs to implement the computation ofthe cumulative effect of one of the structural shocks ut on one of the
endogenous variable.Assume that we have the (reduced-form) VAR
yt = c +1yt1 + . . .pytp + t.
As was shown previously, one can always write a VAR(p) as a VAR(1),by stacking yt,yt1, . . .ytp+1 in a vector y
t . Consequently, let usconsider only the VAR(1) case:
yt = c + yt1 + t.
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Structural VARVector Auto-Regressions:Impulse responses
Once more, let us consider the Wolds form of yt:
yt = c + t + (c + t1) + . . . + k (c + tk) + . . .
= c + But + (c + But1) + . . . + k (c + Butk) + . . .
Consequently, the cumulated effect of the first structural shock u1,t onthe endogenous variables is obtained by computing
(B +
B + . . . +k
B + . . .)
0
...0
if the initial shock of u1,t is of magnitude .
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Vector Auto-Regressions:Impulse responses
In this context, consider the following long-run restriction: the jth
structural shock does not affect,in a cumulative way, the ith
endogenous variable.
Then, denoting with the matrix (I ++ . . . +k + . . .)B, it comesthat the entry (i,j) of must be equal to zero.
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A simple SVAR
It can be noted that short-run restrictions are simpler to implementthan long-run one.
There are particular cases in which some well-known matrixdecompostion can be used to easily estimate some specific SVAR.
Imagine a context in which you can argue that there exists an
ordering of the shocks:A first shock (say, 1,t) can affect instantaneously (i.e., in t) only oneof the endogenous variable (say, y1,t);A second shock (say, 2,t) can affect instantaneously (i.e., in t) thefirst two endogenous variables (say, y1,t and y2,t);
...
Exercise 4
In such a context, what is the form of the matrix B?
Suggest a methodology to estimate such a SVAR.
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Cholesky decomposition: Illustration
Dedola and Lippi (The Monetary Transmission Mechanism: Evidencefrom the Industries of Five OECD Countries, 2005) estimate 5structural VAR for the US, the UK, Germany, France and Italy toanalyse the monetary-policy transmission mechanisms.
They estimate an SVAR over the period 1975-1997, using 5 lags in
VAR.
The shock-identification scheme is based on Cholesky decompositions,the ordering of the endogenous variables being: the industrialproduction, the consumer price index, a commodity price index, the
short-term rate, a monetary aggregate and (except for the US).This ordering implies that monetary policy reacts to the shocksaffecting the first three variables but that the latter react to monetarypolicy with a one-period lag.
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Responses of Macro-variables to a monetary policy shock
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Responses of Macro-variables to a monetary policy shock
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Illustration: Blanchard and Quah (1989)
The article The Dynamics Effects of Aggregate Demand and SupplyDisturbances (AER, 1989) implements long-run restrictions in asmall-sized VAR.
Two variables are considered GDP and unemployment.
Consequently, the VAR is affected by two types of shocks.
The authors want to identify supply shocks (that xan have apermanent effect on output) and demand shocks (that can not have a
permanent effect on output).
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Illustration: Blanchard and Quah (1989)
The motivation of the authors regarding their long-run restrictions can
be obtained from a traditional Keynesian view of fluctuations.The authors propose a variant of a model from Stanly and Fisher(1977)
Yt = Mt Pt + a.t (2)
Yt = Nt + t (3)
Pt = Wt t (4)
Wt = W |
Et1Nt = N
(5)
To close the model, the aithors assume the following dynamics for themoney supply and the productivity
Mt = Mt1 + dt
t = t1 + st
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Illustration: Blanchard and Quah (1989)
In this context, it can be shown that
gnpt = dt
dt1 + a.(
st
st1) +
st
ut = dt a
st
Then, it appears that the demand shocks have no long-run impact onoutput. Besides, neither shocks have a long-run impact onunemployment.
The endogenous variable is ( gnpt ut) where gdpt denotes thelogarithm of GNP.
It is assumed to be stationary. Therefore, neither disturbances has along-run effect on unemployment or the rate of change in output.
The long-run restriction implies that the demand shocks also have nolong-run effect on the output level gnp itself.
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Illustration: Blanchard and Quah (1989)
Estimation data: quarterly, from 1950:2 to 1987:4.8 lags.
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Dynamic effects of demand disturbancesHE AMERICAN ECONOMIC REVIEW SEPTEMBER 1989
positions onlymic effects ofces.d and Supply
and and sup-in Figures 1gures 1 and 2of output andthe horizontal. Figures 3-6but now withs around thehump-shaped
oyment. Their
1.401.201.00-0.80 --0.60-0.400.200.00 ,,,
-0.20 0 10 20 30 40-0.40-0.60 -
FIGURE 1. RESPONSE TO DEMAND,-= OUTPUT,- = UNEMPLOYMENT
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Structural VAR
but now withs around the
- . -FIGURE 1. RESPONSE TO DEMAND,-= OUTPUT,
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Dynamic effects of supply disturbanceshump-shapedoyment. Theirquarters. Theine to vanishThe responsesare mirror im-to this aspectussing the ef-llest when thellowing for anemploymentcays the mostchange in theis allowed, thehanges in un-ively unimpor-mand distur-onsistent withmic effects of
- = UNEMPLOYMENT
1.000.800.60 -/0.40-0.20 -0.00 l+q ii i0 10 20 3 0 40-0.20 -
-0.40-0.60-
FIGURE 2. RESPONSE TO SUPPLY, OUTPUT,- = UNEMPLOYMENT
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Structural VARV A R i I l
In the interveningnd output devia- 7.607.40
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Vector Auto-Regressions:Impulse responses
Uutput-gap deifnition
The output gap is the component of GNP that is explained only by demandshocks.
. At the peak re-s an implied coef-four, higher in ab-coefficient. Thatoefficient is higherthan for demandat we expect. Sup-to affect the rela-employment, andtle or no change in
sof Demand andbances.mic effects of eachext step is to assessto fluctuations innt. We do this inrmal, and entails arical time-series ofof output to thesiness cycles. Thedecompositions ofnt in demand and components of unemployment are station-
7.207.001950 1960 1970 1980
FIGURE 7. OUTPUT FLUCTUATIONSABSENTDEMAND
0.100.080.060.040.02 v0.007
-0.04-0.06-0.08-0.101950 1960 1970 1980
FIGURE 8. OUTPUT FLUCTUATIONSDUE TODEMAND
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Variance decomposition
The k quarter-ahead forecast error in output is defined as thedifference between the actual value of output and its VAR-basedforecast.
Variance decompositionConsider the VAR(1): yt = c + yt1 + t where the residuals aresome linear combinations of structural shocks ut (t = But).
Compute k = yt+k Et (yt+k) with respect to ut+1, ut+2, . . . ut+k.
How to compute the contribution of the ith
structural shock on the jth
endogenous variable?
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Vector Auto-Regressions:Impulse responses
66 THE AMERICAN ECONOMIC RE VIEW SEPTEMBER 1989TABLE 2-VARIANCE DECOMPOSITION OF OUTPUT ND UNEMPLOYMENT
(CHANGE IN OUTPUT GROWTH AT 1973/1974; UNEMPLOYMENT DETRENDED)Percentage of Variance Due to Demand:Horizon(Quarters) Output Unemployment
1 99.0 51.9(76.9,99.7) (35.8,77.6)2 99.6 63.9(78.4,99.9) (41.8,80.3)3 99.0 73.8(76.0,99.6) (46.2,85.6)4 97.9 80.2(71.0,98.9) (49.7,89.5)8 81.7 87.3(46.3,87.0) (53.6,92.9)12 67.6 86.2(30.9,73.9) (52.9,92.1)40 39.3 85.6(7.5,39.3) (52.6,91.6)
TABLE 2A-VARIANCE DECOMPOSITION OF OUTPUT AND UNEMPLOYMENT(No DUMMY BREAK, TIME TREND IN UNEMPLOYMENT)Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 45 / 55
Structural VARSmets and Tsatsaronis (1997)
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Smets and Tsatsaronis (1997)
Why does the yield curve predict economic activity? BIS WorkingPaper No.49.
Objective: Investigating why the slope of the yield curve predictsfuture economic activity in Germany and the United States.
Methodology: A structural VAR is used to identify aggregate supply,aggregate demand, monetary policy and inflation scare shocks and toanalyse their effects on the real, nominal and term premiumcomponents of the term spread and on output.
Findings: In both countries demand and monetary-policy shockscontribute to the covariance between output growth and the laggedterm spread, while inflation scares do not.
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 46 / 55
Structural VARYield curve slope (10yr 3mth) vs Output gap Euro area data Source: OECD
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Yield-curve slope (10yr-3mth) vs. Output gap, Euro area data, Source: OECD
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Underlying theoretical model
The authors argue that their model and in particular the restrictionsthey use is consistent with a semi-structural model that reads:
yt = yt + st (Aggregate supply)
yt = 1yt1 + 2yt2 + (1 1 2)yt3 4t1 + st(IS)
it t = 1 (it1 t1) + 2t + 3 (yt yt) + it(Taylor rule)
Rt = t +1
N
Ni=1
Ett+i + t(Fisher equation)
t = 1t + (1 1)Ett+
1 + 2(yt1 yt1)(Phillips curve)
Rt = Et
Ni=1
it+i
(expectation hypothesis)
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 48 / 55
Structural VARVector Auto-Regressions:Impulse responses
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Vector Auto-Regressions:Impulse responses
The identification suggested by the model calls for a mixture of shortand long-run zero restrictions.
The assumption of a vertical long-run Phillips curve implies thatdemand shocks and nominal shocks (which include monetary-policyand inflation-scare shocks) have no long-run impact on the level of
real output.Supply innovations are thus the source of all permanent shocks tooutput.
Demand shocks are distinguished from nominal shocks by the
assumption that the latter do not contemporaneously aff
ect realoutput.
Finally, the authors assume that monetary authorities do not respondcontemporaneously (i.e. within the quarter) to inflation scares.
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 49 / 55
Structural VARThe effect of a supply shock
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The effect of a supply shock
1.6
0.8
0
0.8
1.6
1.0
0.5
0
0.5
1.0
0.8
0.4
0
0.4
0.8
0.8
0.4
0
0.4
0.8
Germany GermanyUnited States United States
Output
Inflation
Term spread
Real component
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 50 / 55
Structural VARThe effect of a supply shock
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The effect of a supply shock
1.0
0.5
0
0.5
1.0
1.0
0.5
0
0.5
1.0
0.8
0.4
0
0.4
0.8
0.8
0.4
0
0.4
0.8
Short rate
Long rate
Inflation component
Term premium
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 51 / 55
Structural VARThe effect of a demand shock
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1.6
0.8
0
0.8
1.6
1.0
0.5
0
0.5
1.0
0.8
0.4
0
0.4
0.8
0.8
0.4
0
0.4
0.8
Germany GermanyUnited States United States
Output
Inflation
Term spread
Real component
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 52 / 55
Structural VARThe effect of a demand shock
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1.0
0.5
0
0.5
1.0
1.0
0.5
0
0.5
1.0
0.8
0.4
0
0.4
0.8
0.8
0.4
0
0.4
0.8
Short rate
Long rate
Inflation component
Term premium
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 53 / 55
Structural VARDecomposition of term-spread/output-growth covariance
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p p / p g
0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0 1 2 3 4 5 6 7 8 9 0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0 1 2 3 4 5 6 7 8 9
Covarianceof which:
SupplyDemand
PolicyInflation scare
Lags (in quarters)
Note: The unconditional covariance between the current output growth and lagged term spread (solid line) is decomposed tothe contributions of the four structural shocks identified in the VAR.
Germany United States
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 54 / 55
References
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Bhar, R. and Hamori, S. (2005). Empirical Techniques in Finance. Ed. SpringerFinance.
Blanchard, O. and Quah, D. (1989). The Dynamic Effects of Aggregate Demandand Supply Disturbances. American Economic Review, vol. 79.
Dedola, L. and Lippi, F. (2005). The monetary transmission mechanism: Evidencefrom the industries of five OECD countries. European Economic Review, vol. 49(6).
Gal, J. (1992). How well does the IS-LM model fit postwar US data? QuarterlyJournal of Economics.
Gerlach, S. and F. Smets (1995). The monetary transmission mechanism: evidencefrom the G7 countries. CEPR Discussion Paper, no. 1219.
Granger, C. (1969). Prediction with a Generalized Cost of Error Function.Operational Research Quarterly, vol. 20.
Hamilton, J. (1994). Time Series Analysis. Princeton University Press.
Sims, C. (1980). Macroeconomics and Reality. Econometrica, vol. 48.
Smets, F. and Tsatsaronis, K. (1997). Why does the yield curve predict economicactivity? BIS Working Paper No. 49.
Jean-Paul Renne (Banque de France) Structural VAR and Applications ENSTA, 22 January 2010 55 / 55