Dear,

I want to impulse unrealized news shock after running Occbin for news shock.

I have read the code for the RBC model and understand the key is to use simult_ to combine the 8 period ahead news shock(1) and the unexpected shock(1+8) that offsets it and makes it fail to realize DSGE_mod/RBC_news_shock_model/RBC_news_shock_model.mod at master · JohannesPfeifer/DSGE_mod · GitHub

matlab/simult_.m · master · Dynare / dynare · GitLab

The issue is, simult_ cannot work after Occbin. After Occbin’s solution algorithm, there is no “ghx”,“ghu”,“state_var”, which are necessary for simult_ .

```
[zdatalinear zdatapiecewise zdatass oobase_ Mbase_ ] = ...
solve_one_constraint(modnam,modnamstar,...
constraint, constraint_relax,...
shockssequence,irfshock,nperiods,maxiter);
for i=1:M_.endo_nbr
eval([deblank(M_.endo_names(i,:)),'_u=zdatalinear(:,i);']);
eval([deblank(M_.endo_names(i,:)),'_p=zdatapiecewise(:,i);']);
eval([deblank(M_.endo_names(i,:)),'_ss=zdatass(i);']);
end
```

Are there any feasible ways to generate unrealized news shocks after Occbin?

Many thanks in advance!

Dear @jpfeifer Johannes, are there any feasible ways to generate unrealized news shocks after Occbin?

Any thoughts will be highly appreciated! Thanks a ton!

Occbin should allow you to specify shocks and then conduct a simulation.

do you mean that simult_ should work after occbin? But the warning information is

```
Reference to non-existent field 'ghu'.
Error in simult_ (line 91)
if isempty(dr.ghu)% For (linearized) deterministic models.
Error in runsim_unrealized_news (line 105)
y2 = simult_(initial_condition_states,oo_.dr,shock_matrix,1); %ERROR, this code only works 4.6
```

I attach the codes that I use to test unrealized news shocks after Occbin below. Please run the runsim_unrealized_news.m file.

replication_figure3_4_news.rar (1.9 MB)

I have another question about the code. Should I specify the shocks(unrealized) before occbin solution algorithm? That is, should I specify the shock matrix before `solve_two_constraints`

?

Thanks so much and wish you a good day!

No, what I am saying is that `solve_*_constraint`

has an input `shockssequence`

that allows you to put in the two shocks necessary to run a pure news shock.

Dear Johannes, do you mean I actually only need to simply modify like this before `solve_*_constraint`

```
irfshock =char('eps_j4','eps_j');
shock_matrix = zeros(40,2);
shock_matrix(2,1) = 0.1;
shock_matrix(2+4,2) = - 0.1;
shockssequence= shock_matrix;
nperiods = numel(shockssequence);
```

I attach the new runsim_unrealized_news1.m for your quick reference.

Is this result really the result of the economy hit by an unrealized news shock?

runsim_unrealized_news1.m (3.9 KB)

Many Thanks in advance!

So I do NOT need to use `simult_`

below anymore. These results, `"endogenousvariables"_p`

, `"endogenousvariables"_ss`

, are already the results of the unrealized news shock. Right?