How to shock a Parameter

Hello, I am trying to simulate my model considering a shock to a parameter (parameter Tau), instead of the canonical shock to the technological process. Any suggestion on how to perform this task?

I attach the mod file with the model

Thank you very much for the help!mynodel2.mod|attachment (1.8 KB)mynodel2.mod (1.8 KB)

Are you sure that you want to shock a parameter and not a variable? Because by definition a parameter, simply speaking, is fixed and does not change.

You are right, I will try to be more precise:
my goal is to investigate how the outcome changes if I change only that parameter value. I do not want any shock to any variable to happen (i.e. no shock to the technology)

I still don’t seem to understand what you are trying to do. What exactly do you mean by “outcome changes” combined with “no shock to the technology”?
You have a log-linearized model, hence steady states of the endogenous variables are zero. So in order to investigate how a different parameter affects the outcome you have to impose some shock, right? If this is what you want to do, why not run the model twice with two different parametrizations and compare the two?
Or are you after something else?