# Counterintuitive impulse responses in a SVAR model, why?

I did a study with structural vector autoregression (SVAR model) corresponding to the IS-LM model (a macroeconomic model). I have four variables that are I(1). I have fitted the SVAR model to the first differences of the original variables. I analysed the impulse response function (IRF). The interpretation of the IRF was contradictory to the economic reality.

Questions:

1. What could be the causes of such result?
2. Could it be due to cointegration between variables?
• I was going through my old answers and noticed this one was not accepted. Do you perhaps need further clarification? – Richard Hardy Mar 16 '20 at 15:20