with George Alessandria and Yan Bai

Journal of Monetary Economics, Volume 113, August 2020

Abstract: During sovereign debt crises, countries experience persistent economic declines, spiking spreads, and outflows of capital and workers. To account for these salient features, we develop a sovereign default model with migration and capital accumulation. The model has a two-way feedback. Default risk lowers workers’ welfare and induces emigration, which in turn intensifies default risk by lowering tax base and investment. Compared with a no-migration model, our model produces higher default risk, lower investment, and a more profound and prolonged recession. We find that migration accounts for almost all of the lack of recovery in GDP during the recent Spanish debt crisis.

with Min Fang

European Economic Review, Volume 144, May 2022

Abstract: We study how debt maturity heterogeneity determines firm-level investment responses to monetary policy shocks. We first document that debt maturity significantly affects the responses of firm-level investment to conventional monetary policy shocks: firms who hold more long-term debt are less responsive to monetary shocks. The magnitude of responses due to debt maturity heterogeneity is comparable to the well-documented responses due to debt level heterogeneity. Evidence from credit ratings and borrowing responses indicates that the higher future default risk embedded in long-term debt plays an essential role. We then develop a heterogeneous firm model with investment, long-term and short-term debt, and default risk to quantitatively interpret these facts. Conditional on the level of debt, firms with more long-term debt are more likely to default on their external debt and consequently face a higher marginal cost of external finance. As a result, these firms are less responsive in terms of investment to expansionary monetary shocks. The effect of monetary policy on aggregate investment, therefore, depends on the distribution of debt maturity.

American Economic Journal: Macroeconomics, Volume 16, April 2024 (pp. 217-49)

Abstract: Income inequality and worker migration significantly affect sovereign default risk. Governments often impose progressive taxes to reduce inequality, which redistribute income but discourage labor supply and induce emigration. Reduced labor supply and a smaller high-income workforce erode the current and future tax base, reducing government’s ability to repay debt. I develop a sovereign default model with endogenous nonlinear taxation and heterogeneous labor to quantify this effect. In the model, the government chooses the optimal combination of taxation and debt, considering its impact on workers’ labor and migration decisions. Income inequality accounts for one-fifth of the average US state government spread.

Working Papers

with Chang Liu (NUS)

R&R, Review of Economic Dynamics 

Abstract: This paper analyzes the impact of a balanced budget rule (BBR) on government financing costs and its implications for the government balance sheet. Exploiting the variation in BBR implementation across US states, we find that states with more stringent BBRs exhibit significantly lower bond spreads and credit default swap spreads, demonstrating the crucial role of default risk. A sovereign default model, which features long-term debt, endogenous investment and output, as well as a BBR, aligns with the empirical result. Calibrated to Illinois, our quantitative analysis suggests that implementing a BBR could dramatically decrease the state bond spread, gradually lower the debt, and improve welfare in the long run.

with Chang Liu (Rochester)

R&RJournal of International Economics

Abstract: This paper measures the output and TFP losses from sovereign risk, considering firm-level intangible investment. Using Italian firm-level data, we show that firms reallocated from intangible assets to tangible assets during the recent sovereign debt crisis. This asset reallocation is more pronounced among small firms and high-leverage firms. This reallocation affects aggregate output and TFP. To explain the reallocation pattern and quantify the output and TFP losses of sovereign debt crises, we build a sovereign default model incorporating firm intangible investment. In our model, sovereign risk deteriorates bank balance sheets, disrupting banks’ ability to finance firms. Firms with greater external financing needs are more exposed to sovereign risk. Facing tightening financial constraints, firms shift their resources towards tangibles because they can be used as collateral. Using the estimated model, we find that elevated sovereign risk explains 45% of the observed output losses and 31% of TFP losses during the Italian sovereign debt crisis.

 with Zhiyuan Chen and Min Fang

Selected Work In Progress

with George Alessandria, Yan Bai, and Chang Liu (Rochester)

with George Alessandria, Yan Bai, and Chang Liu (Rochester)

with Min Fang, Philipp Renner, and Simon Scheidegger