Impulse Response Function - Negative Shocks on R I have two questions on how to produce impulse responses using R

(1) Impulse responses to a negative shock in the independent variable (money supply)

(2) Impulse responses at 2 standard deviations

The code I used to generate the impulse responses to a positive shock at 1 standard deviation is the following:

m1 &lt;- read.csv("m1.csv", header=T)

m1

varm1 &lt;- VAR(m1, p=8, type="cons")

irfm1 &lt;- irf(varm1, impulse="m1", response= c("gdp"), boot = FALSE)

plot(irfm1)

irfm1
Here is a simple example that should work:

library(vars)
data("Canada")
var.2c=VAR(Canada,p=2,type="const")
# 1 SD impulse reponse function
irf.rw.e=irf(var.2c,impulse="rw",response=c("e"))
# gamma is the number of standard deviations for the irf
gamma=-0.25
irf.rw.e_gamma = irf.rw.e
n=length(irf.rw.e_gamma$irf$rw)
for(i in 1:n){
    irf.rw.e_gamma$irf$rw[i]   = irf.rw.e_gamma$irf$rw[i]*gamma
    irf.rw.e_gamma$Lower$rw[i] = irf.rw.e_gamma$Lower$rw[i]*gamma
    irf.rw.e_gamma$Upper$rw[i] = irf.rw.e_gamma$Upper$rw[i]*gamma
} 
plot(irf.rw.e)
plot(irf.rw.e_gamma)


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