Working Papers
Joint with Jesús Fernández-Villaverde, Galo Nuño and Omar Rachedi
May 2023
This paper studies how household inequality shapes the effects of the zero lower bound (ZLB) on nominal interest rates on aggregate dynamics. To do so, we consider a heterogeneous agent New Keynesian (HANK) model with an occasionally binding ZLB and solve for its fully non-linear stochastic equilibrium using a novel neural network algorithm. In this setting, changes in the monetary policy stance influence households' precautionary savings by altering the frequency of ZLB events. As a result, the model features monetary policy non-neutrality in the long run. The degree of long-run non-neutrality, i.e., by how much monetary policy shifts real rates in the ergodic distribution of the model, can be substantial when we combine low inflation targets and high levels of wealth inequality.
January 2023
I develop a framework for studying media of exchange within Heterogenous Agent New Keynesian (HANK) models. To this end, I extend an otherwise standard HANK model with search-theoretic monetary frictions as in Lagos and Wright (2005). I show that the medium of exchange role of money breaks monetary super-neutrality in HANK, meaning that changes in the central bank's inflation target affect real variables and the wealth distribution in the long run. The extent of non-neutrality can be substantial, with aggregate consumption declining by 0.74% after an increase in the central bank's inflation target from 0% to 5%. I then apply the framework to study how heterogeneity in the dependence on non-interest-bearing payment instruments shapes the welfare costs of inflation across wealth and income distributions. I show quantitatively that the welfare costs of inflation are about 8% higher for the wealth- and income-poor households in the economy. The result stems from the fact that poor households, in line with microdata, depend more on non-interest-bearing payment instruments, such as cash.
January 2022
This paper develops a New Keynesian model that features endogenous build-ups of financial imbalances, where financial crises typically follow credit booms and are characterized by sharp output drops. A quantitative analysis of the model shows that if the macroprudential authority does not implement the optimal policy, a central bank that is leaning against the wind, i.e. sets higher interest rates in response to build-ups of imbalances, reduces the frequency of financial crises and improves welfare at the cost of more volatile inflation. The result stems from a failure of the `divine coincidence' due to financial frictions in the banking sector.