Suppose, today, one to inflationary expectations is no, p age = 0, therefore, the MM( p e = 0) bend is applicable
Goods market and money market equilibrium implies that we achieve equilibrium E where money supply is M/p0 and real and nominal interest rates are equal to each other at i0 = r0. We can now trace out the consequences of an exogenous increase in inflationary expectations. By raising inflationary expectations to some positive amount, p e > 0, the MM curves shifts down to MM( p e >0). The new equilibrium rate of real interest, rstep step one, is at point F in Figure 13, where MM( p e >0) and YY intersect. However, as now i = r + p e , then a “wedge” of size p e is created between the old MM curve and the new one: the new real rate r1 is read off the intersection of YY and the new MM curve (point F) and the new nominal rate i1 is read off the top curve MM( p e =0) at the same level of money supply (point G). Obviously, then, the introduction of inflationary expectations has increased the nominal interest rate from i0 to i1, but the amount of the increase is less than the full amount of expectations, p e .
