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Econ 240C. Lecture 17. Part I. VAR. Does the Federal Funds Rate Affect Capacity Utilization?. The Federal Funds Rate is one of the principal monetary instruments of the Federal Reserve Does it affect the economy in “real terms”, as measured by capacity utilization. Preliminary Analysis.
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Econ 240C Lecture 17
Part I. VAR • Does the Federal Funds Rate Affect Capacity Utilization?
The Federal Funds Rate is one of the principal monetary instruments of the Federal Reserve • Does it affect the economy in “real terms”, as measured by capacity utilization
Estimation Results • OLS Estimation • each series is positively autocorrelated • lags 1 and 24 for dcapu • lags 1, 2, 7, 9, 13, 16 • each series depends on the other • dcapu on dffr: negatively at lags 10, 12, 17, 21 • dffr on dcapu: positively at lags 1, 2, 9, 10 and negatively at lag 12
We Have Mutual Causality, But We Already Knew That DCAPU DFFR
Interpretation • We need help • Rely on assumptions
What If • What if there were a pure shock to dcapu • as in the primitive VAR, a shock that only affects dcapu immediately
The Logic of What If • A shock, edffr , to dffr affects dffr immediately, but if dcapu depends contemporaneously on dffr, then this shock will affect it immediately too • so assume b1 iszero, then dcapu depends only on its own shock, edcapu , first period • But we are not dealing with the primitive, but have substituted out for the contemporaneous terms • Consequently, the errors are no longer pure but have to be assumed pure
DCAPU shock DFFR
Standard VAR • dcapu(t) = (a1 + b1 a2)/(1- b1 b2) +[ (g11+ b1 g21)/(1- b1 b2)] dcapu(t-1) + [ (g12+ b1 g22)/(1- b1 b2)] dffr(t-1) + [(d1+ b1 d2 )/(1- b1 b2)] x(t) + (edcapu(t) + b1 edffr(t))/(1- b1 b2) • But if we assume b1 =0, • thendcapu(t) = a1 +g11 dcapu(t-1) + g12 dffr(t-1) + d1 x(t) + edcapu(t) +
Note that dffr still depends on both shocks • dffr(t) = (b2 a1 + a2)/(1- b1 b2) +[(b2 g11+ g21)/(1- b1 b2)] dcapu(t-1) + [ (b2 g12+ g22)/(1- b1 b2)] dffr(t-1) + [(b2 d1+ d2 )/(1- b1 b2)] x(t) + (b2edcapu(t) + edffr(t))/(1- b1 b2) • dffr(t) = (b2 a1 + a2)+[(b2 g11+ g21) dcapu(t-1) + (b2 g12+ g22) dffr(t-1) + (b2 d1+ d2 ) x(t) + (b2edcapu(t) + edffr(t))
Reality edcapu(t) DCAPU shock DFFR edffr(t)
What If edcapu(t) DCAPU shock DFFR edffr(t)
Interpretations • Response of dcapu to a shock in dcapu • immediate and positive: autoregressive nature • Response of dffr to a shock in dffr • immediate and positive: autoregressive nature • Response of dcapu to a shock in dffr • starts at zero by assumption that b1 =0, • interpret as Fed having no impact on CAPU • Response of dffr to a shock in dcapu • positive and then damps out • interpret as Fed raising FFR if CAPU rises
What If edcapu(t) DCAPU shock DFFR edffr(t)
Standard VAR • dffr(t) = (b2 a1 + a2)/(1- b1 b2) +[(b2 g11+ g21)/(1- b1 b2)] dcapu(t-1) + [ (b2 g12+ g22)/(1- b1 b2)] dffr(t-1) + [(b2 d1+ d2 )/(1- b1 b2)] x(t) + (b2edcapu(t) + edffr(t))/(1- b1 b2) • if b2 = 0 • then, dffr(t) = a2 + g21 dcapu(t-1) + g22 dffr(t-1) + d2 x(t) + edffr(t)) • but, dcapu(t) = (a1 + b1 a2) + (g11+ b1 g21) dcapu(t-1) + [ (g12+ b1 g22) dffr(t-1) + [(d1+ b1 d2 ) x(t) + (edcapu(t) + b1 edffr(t))
Interpretations • Response of dcapu to a shock in dcapu • immediate and positive: autoregressive nature • Response of dffr to a shock in dffr • immediate and positive: autoregressive nature • Response of dcapu to a shock in dffr • is positive (not - ) initially but then damps to zero • interpret as Fed having no or little control of CAPU • Response of dffr to a shock in dcapu • starts at zero by assumption that b2 =0, • interpret as Fed raising FFR if CAPU rises
Conclusions • We come to the same model interpretation and policy conclusions no matter what the ordering, i.e. no matter which assumption we use, b1 =0, or b2 =0. • So, accept the analysis
Understanding through Simulation • We can not get back to the primitive fron the standard VAR, so we might as well simplify notation • y(t) = (a1 + b1 a2)/(1- b1 b2) +[ (g11+ b1 g21)/(1- b1 b2)] y(t-1) + [ (g12+ b1 g22)/(1- b1 b2)] w(t-1) + [(d1+ b1 d2 )/(1- b1 b2)] x(t) + (edcapu(t) + b1 edffr(t))/(1- b1 b2) • becomes y(t) = a1 + b11 y(t-1) + c11 w(t-1) + d1 x(t) + e1(t)
And w(t) = (b2 a1 + a2)/(1- b1 b2) +[(b2 g11+ g21)/(1- b1 b2)] y(t-1) + [ (b2 g12+ g22)/(1- b1 b2)] w(t-1) + [(b2 d1+ d2 )/(1- b1 b2)] x(t) + (b2edcapu(t) + edffr(t))/(1- b1 b2) • becomes w(t) = a2 + b21 y(t-1) + c21 w(t-1) + d2 x(t) + e2(t)
Numerical Example y(t) = 0.7 y(t-1) + 0.2 w(t-1)+ e1(t) w(t) = 0.2 y(t-1) + 0.7 w(t-1) + e2(t) where e1(t) = ey(t) + 0.8 ew(t) e2(t) = ew(t)
Generate ey(t) and ew(t) as white noise processes using nrnd and where ey(t) and ew(t) are independent. Scale ey(t) so that the variances of e1(t) and e2(t) are equal • ey(t) = 0.6 *nrnd and • ew(t) = nrnd (different nrnd) • Note the correlation of e1(t) and e2(t) is 0.8
Analytical Solution Is Possible • These numerical equations for y(t) and w(t) could be solved for y(t) as a distributed lag of e1(t) and a distributed lag of e2(t), or, equivalently, as a distributed lag of ey(t) and a distributed lag of ew(t) • However, this is an example where simulation is easier