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forcst function in Metropolis

PostPosted: Mon Mar 06, 2006 8:52 pm
by azj
I noticed that in 3_064, each call to the forcst2 function in metropolis.m asks for only one forecast. ie:

yf1 = forcst2(yyyy,horizon,dr_,1);

In previous versions, the last argument passed to forcst2 was "B" (which at the time was set to 100, currently 500) instead of 1. Is there a reason that this version uses only 1 draw of the future shocks to determine the forecast uncertainty from the parameters and the future shocks?

Thanks,
Ariel

PostPosted: Mon Mar 06, 2006 9:20 pm
by MichelJuillard
Yes, this call takes place in a loop over B draws among metropolis iterations.

At first, I thought it was necessary to sample more for parameter uncertainty and intrinsic shocks, then I revised this opinion. I don't think anymore it is necessary to do B draws to describe parameter uncertainty and B*B draws for parameter uncertainty and intrinsic shocks

Of course, we should make B a parameter that users can tune. But as you have found it, you can now tune it by hand :)

Best

Michel