Is there anyway to stipulate that in a stochastic model the exogenous shock is negative. e.g. instead of producing impulse response graphs for a positive shock it produces one for a negative shock?
Many thanks and my apologies if this question turns out to have an obvious and already explained answer.
There is no option to do that in Dynare, but if you change the sign of the shock in the model, a positive impulse to the modified shock will give you the response to a negative impulse to the original shock.