Working Paper（23-013E）Inflation and entry costs in a monetary search model

In this study, we construct a variant of the Lagos-Wright monetary model in which both buyers and sellers optimally decide whether to enter decentralized mar- ket by paying fixed entry costs. In the decentralized market, the sellers produce the intermediate inputs which are necessary to produce the general good traded in the centralized market. We show that the Friedman rule of setting nominal interest rate to zero may not be optimal. The optimal inflation rate is derived explicitly for specific functional forms. It is shown that the optimal inflation rate is lower for lower buyer entry costs, because the lower entry costs generate the congestion of buyers which must be compensated for by lower cost of money holdings. It is also shown that the optimal inflation is lower for higher seller entry costs. These results may explain why the secular decline in inflation has been observed in recent decades when the emergence and growth of Internet usage has lowered shopping costs for buyers.

Keywords : Optimal monetary policy; entry cost; competitive pricing; low inflation.

JEL classification code: E13; E42; E52