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How to access numbers for bootstrap-based confidence bands after VAR, IRF

Posted: Fri Jul 02, 2021 8:12 am
by p2021
After estimating a VAR and using a certain Cholesky ordering assumption, I’d like to access the numbers for Kilian’s unbiased bootstrap-based standard errors for the IRFs for different cilevels.

To do so, I first estimate a VAR and name it myvar. Then I run, for example:

myvar.impulse(30, m, se=boot, bs=ku, fdb, rep=999, smat=my1, cilevels=0.95) [and click through the Cholesky options]

This produces two matrices, my1 and my1_se.
The matrix my1 contains the expected numbers for the IRF point estimates.
But the matrix my1_se contains zeros only.
This must be a bug...
(If I instead run, for example, myvar.impulse(30, m, se=a, smat=my2, cilevels=0.95), my2_se contains the expected entries, not zeros.)

Given that the above procedure fails, is there currently any other way to access what should have been in my1_se?

Peter

Re: How to access numbers for bootstrap-based confidence bands after VAR, IRF

Posted: Tue Oct 05, 2021 8:42 am
by EViews Mirza
Hi Peter!

This has now been fixed. It should go out in the next patch.

Now that the all zero-matrix has been fixed, it's important to mention here that the command you're using to retrieve bootstrap CIs would not do the intended operation. In particular, issuing smat=mymat will produce a matrix of bootstrap standard errors and NOT bootstrap CIs, and I believe what you're after are the CIs and not the SEs.

Hence, in the next patch, there will be another set of option keywords:

1) cimat
2) rcimat

The first will produce a matrix of consisting only of CIs in (lower, upper) pairs for each impulse response combination. The second is similar to cimat but will prepend to each (lower, upper) pair the impulse response combination to which it is associated. In fact, the rcimat will work even if you didn't perform a boootstrap, but did obtain the SEs. In the latter case, the (lower, upper) combination will be the equivalent of a lower and upper SE band. In any case, the idea here is that rcimat is be better suited if you wish to produce your own graphs.

As I said, all of this will be going out in the next patch and you'll be able to play with it then.

Re: How to access numbers for bootstrap-based confidence bands after VAR, IRF

Posted: Thu Mar 23, 2023 3:49 pm
by houji
Hi,

I had a concern regarding rcimat with bootstrap, Eviews13

It seems that the series are not in order. The responses are interleaved between the confidence intervals, so it is hard to use the matrix to manually create charts.

Code: Select all

create u 50 series x = rnd series y = x + rnd series z = nrnd var v.ls 1 2 x y z matrix struct_to_endog = @cholesky(v.@residcov) ' The structural factorization matrix freeze(temp) v.impulse(imp=user, fname=struct_to_endog, se=boot, bs = sp, rep=50,cilevels = "0.68 0.9",rcimat = mata) ' Reference multigraph

Re: How to access numbers for bootstrap-based confidence bands after VAR, IRF

Posted: Wed Apr 26, 2023 9:10 am
by EViews Glenn
What chart do you wish to create? The interleaving is chosen specifically to make it easier to create standard charts.