Should We Be Afraid of Friedman’s Rule?

Should one think of zero nominal interest rates as an undesirable liquidity trap or as the desirable Friedman rule? I use three different frameworks to discuss this issue. First, I restate H. L. Cole and N. Kocherlakota’s (1998, Fed. Res. Bank Minn. Quart. Rev., Spring, 2–10) analysis of Friedman’s rule: short run increases in the money stock—whether through issuing spending coupons, open market operations, or foreign exchange intervention— change nothing as long as the money stock shrinks in the long run. Second, two simple Keynesian models of the inflationary process with a zero lower bound on nomianl interest rates imply either that deflationary spirals should be common or that a policy close to the Friedman rule and thus some deflation is optimal. Finally, a formal baby-sitting coop model implies multiple equilibria, but does not support the injection of liquidity to restore the good equilibrium, in contrast to P. Krugman (1998, Slate, August 13). J. Japan. Int. Econ., December 2000, 14(4), pp. 261–303. CenER, Tilburg University; Humboldt University, Berlin, Germany; and CEPR. c © 2000 Academic Press