Date of Award

Spring 5-15-2020

Author's School

Graduate School of Arts and Sciences

Author's Department


Degree Name

Doctor of Philosophy (PhD)

Degree Type



This thesis consists of three self-contained articles. In the first article "The Common Currency Channel of Risk Sharing", I propose a new channel of international risk sharing: the common currency channel. I show theoretically that the central bank of a currency union can use the common currency to insure member countries against consumption risk from idiosyncratic productivity shocks. A trade-off between risk-sharing and moral hazard emerges: a central bank which enables risk sharing induces countries to free ride on each other’s production efforts. I study this trade-off and derive rules for a central bank striking the optimal balance between insurance and incentives. Monetary policy determines current account imbalances that are financed through the central bank. Optimal policy is contingent on the realization of aggregate production. The central bank should lower its policy rate in response to a decrease in aggregate production to provide insurance through the common currency. Revisiting European Central Bank policies during the Eurocrisis between 2008 and 2014, I interpret the buildup of TARGET2 balances as risk sharing through the common currency. I find that this channel accounts for up to 60% of risk sharing among Eurozone countries in the early stages of the Eurocrisis. I conclude that the common currency can be a substitute for risk sharing through fiscal integration. The second article "Riding the Cycle" (joint work with Christoph Wolf) studies the interplay between the business cycle and financial contracting. If the success probability of an investment project is increasing in both the business cycle state and the borrower’s effort, then the borrower can free-ride on the cycle. In a model of financial contracting with moral hazard, we show that this free-riding generates procyclical agency costs. The overall effect of business cycle conditions on credit availability depends on how changes in agency costs compare to cycle-induced changes in the net present value of investment projects. In a dynamic extension, we endogenize the business cycle as a function of the output realized through past credit contracts. The dynamic economy has a unique stable steady state. If agency frictions in the economy are sufficiently strong, a small shock to the business cycle can cause the economy to fluctuate between business cycle ups and downs. The cycles are induced by the interplay of the negative agency cost effects and the positive output effects of the business cycle. Our theory sheds new light upon the observed patterns of secured and unsecured credit in U. S. data from 1981 to 2012. The third article "Diversity Taxes" (joint work with Saumya Deojain) studies how social conflict generated through cultural diversity affects public policy. In our model, social conflict arises when diverse groups impose negative consumption externalities on each other. These externalities can be mitigated by a government which transforms cultural consumption into public good consumption. We show that in such a framework, ‘diversity taxes’ arise as a policy tool to regulate the externalities from the cultural consumption of diverse groups. We link the size of such taxes to characteristics of the underlying distribution of cultural groups as well as to the type of government (majority and minority). In contrast to much of the literature, our analysis predicts that more diverse communities have a bigger government size as measured by local taxes per capita. Using U. S. city and county data from 1990, we are able to verify this prediction. We find strong evidence for the existence of sizeable ’diversity taxes’ in U. S. localities after controlling for a variety of socioeconomic and demographic indicators. We further document statistically significant relationships between characteristics of the group size distribution and local taxes per capita which are in line with our hypothesized link between cultural diversity, negative externalities, and taxation.


English (en)

Chair and Committee

Costas Azariadis

Committee Members

Gaetano Antinolfi, Ana Babus, Jason R. Donaldson, Fernando M. Martin,

Included in

Economics Commons