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Problem with Ramsey code and Blanchard Kahn conditions

PostPosted: Mon Jan 12, 2015 11:15 am
by angiea33
Hi,

I am running into problems when using the ramsey policy code in the context of my model.

If I solve the model without the ramsey policy, I have no problems finding the steady state. When I instead implement the ramsey policy code I get the following:

Error using print_info (line 42)
Blanchard Kahn conditions are not satisfied: no stable equilibrium
Error in stoch_simul (line 98)
print_info(...)
Error in ransey_policy (line 25)
info = stoch_simul(var_list);
..........................

Here is the procedure:

1) Plug in a guess for R in the initval block
initval;
R = Rguess;
end;

2) In the steady_state_model block I define
R = Rguess use an external function that finds the steady state of c given R and the parameters. Note: R and not Rguess
c = find_SS(R, paramset)

3) Given c, I define the remaining ss variables recursively.

If I use stoch_simul dynare is able to find the steady state. However, as soon as I implement the ramsey policy command lines I run into trouble.
It would be great if someone could help me with this! I was not able to find a solution in the Forum.

Many thanks in advance,

Angela

Re: Problem with Ramsey code and Blanchard Kahn conditions

PostPosted: Mon Jan 12, 2015 11:23 am
by angiea33
Sorry I forgot to mention that I am using Dynare 4.4.2 and also that

1) Debugging I noticed that the code gets stuck at the Initial value (the correct ss)
2) I changed the Initial value, and then get a different error message (steady state is complex)
3) If I remove the R = Rguess from the steady state block then the find_SS gets stuck at a value slightly different from the Initial value. If I plug in this new Initial value in the code without Ramsey, dynare is able to find a steady state and it is stable

So I guess there must be a problem with my coding but I am not able to find which one it is. Maybe someone has a quick answer :P

Re: Problem with Ramsey code and Blanchard Kahn conditions

PostPosted: Thu Jan 22, 2015 12:45 pm
by jpfeifer
Please try the unstable version and report back. If it does not work, send me the files.