# Reverse of the stochastic shock at a later period

Dear all,

I am a complete beginner to dynare. I am using it in my master thesis to simulate what happens if two countries, Home and Foreign, share an unemployment insurance (inspired by Moyen, Stähler, and Winkler). I have an extremely simple model where I would like to simulate diverging business cycles. That means, the same shock is affecting Home negatively and Foreign positively.

My question is, how can I reverse the shock in the period when the things have returned to the steady state? In other words, how do I generally introduce a stochastic shock at a later period?

I hope this is not too stupid a question. I would also like to thank you for this fantastic forum which is the best resource about dynare available!

Best regards,
Kate

model_notransfers.mod (3.4 KB)

Is this reversal known in advance? In any case, you can use the `simult_`- function to manually set the shock matrix. See
https://github.com/JohannesPfeifer/DSGE_mod/blob/master/RBC_news_shock_model/RBC_news_shock_model.mod

Dear Prof. Pfeifer,

Thank you very much for your response. No, the reversal is not known in advance. The idea is that a boom turns later into a bust, after let’s say 100 periods. So I would like to introduce a second stochastic shock (“e_f”) at the 101st period.

I tried to write such shock matrix (here: model_notr_rever.mod (3.7 KB)
) but everything still happens only in the first period. Either I didn’t do it right or it is not what I need. Maybe you have another hint for me? Thank you so much!

Best regards,
Kate

I have made it work! The solution model_notr_rever2.mod (3.9 KB)

Dear Prof. Pfeifer,

Now that I managed to simulate my shocks, I am struggling to access the statitistics of the simulation. What dynare shows me as default output, seems to be the statistics of the stoch_simul which I run first. How do I let it show me the output of my simult_ command? I am interested in means and standard deviations.

Yes. When you use `simult_` you need to compute those objects manually