Mitä on markkinamonetarismi?

Scott Sumner selittää, mitä on markkinamonetarismi. Olen aiemmin pyrkinyt kuvaamaan sitä, miksi Euroopan keskuspankin tekemällä rahapolitiikalla on valtavasti väliä Suomenkin kansantalouden pärjäämiselle (mm. täällä).

4.  Money matters, beyond the impact on interest rates.  But we don’t make any assumption about the stability of V (unlike traditional monetarists.)  Money matters because of the “hot potato effect.”  That is, the Fed determines the supply of base money and the public determines the real quantity of base money and the “Cambridge k,” which is the ratio of the base to NGDP.  In the long run “k” moves independently of once-and-for-all changes in the base.  That’s because once-and-for-all changes in the base have little or no effect on interest rates in the very long run.   Hence once-and-for-all changes in the base have a roughly proportional effect on long run NGDP.  We believe that unless you explicitly model money, you can’t explain why NGDP is not 1000 times higher or lower.

Put simply, we assume that a big crop of new currency lowers the value of money (i.e. its purchasing power) for the same reason that a big crop of apples lowers the value of an apple.