restrictive monetary policy and vice versa: Expansive monetary policy results in restric- tive fiscal policy. Unlike Melitz (2000), another author who looked into empirical re- search of the interaction, Wyplosz (1999), makes the estimation of reactive functions of monetary and fiscal policy individually, separately (Melitz estimated the equations of monetary policy simultaneously). Short-term interest rate is an instrument of monetary policy, and primary budget balance (in our contribution similarly) is an instrument of fiscal policy. He concludes that monetary authority works in line with the economic theory. As the rate of inflation increases, central bank increases the interest rate; when output gap lowers, central bank decreases the interest rates. Fiscal policy works in line of this theory as well. It reacts in a stabilizing way to the output gap and partly to the rate of inflation, too. His other conclusion is that monetary policy does not react to fis- cal policy. On the other hand, certain statistically significant reactions of fiscal policy to monetary policy were found.
Řežábek (2011) is one of the Czech authors who deal with this problem. He researches mutual impact of monetary and fiscal policy by a different estimation of a potential product (the output gaps of both policies) through simultaneous equations estimation.