Inflation and Interest Rates with Endogenous Market Segmentation

We examine a monetary economy wherein endogenous asset market segmentation permits the extent of household participation in open market operations to vary smoothly with changes in aggregate conditions. While we impose no stickiness at the microeconomic level in either prices or portfolio adjustment, we find that our flexible asset market segmentation can deliver gradual adjustment in the aggregate price level following a monetary shock and thus persistent non-neutralities. In our model economy, households incur fixed transactions costs when exchanging bonds and money and, as a result, carry money balances in excess of current spending to limit the frequency of such trades. As only a fraction of households choose to actively trade bonds and money at any given time, asset markets are endogenously segmented. Because our households can alter the timing of their trading activities, the extent of market segmentation varies over time in response to real and nominal shocks, as does the distribution of real balances across households. We show that this added flexibility can substantially reinforce the sluggishness in aggregate price adjustment following a monetary shock, relative to models with exogenously segmented asset markets, and it can transform dramatic, transitory changes in real and nominal interest rates into more moderate and persistent liquidity effects. We also show that, following an endowment shock, changes in households' portfolio adjustment timing generate persistence in inflation and interest rates that is otherwise absent. Finally, we show that these changes can reshape aggregate quantity dynamics in a version of the model with production, generating hump-shaped responses in employment and output following a monotone shock to productivity.