Working Papers
We study the cross-section of currencies using a quantitative macroeconomic model with heterogeneous countries, segmented asset markets, and risk-averse financial intermediaries. The model admits a two-factor structure of bilateral exchange rates. The factors combine global business cycle shocks and financial shocks that reprice the business cycle risk. Countries' exposures to these factors are heterogeneous and depend on their reliance on commodity exports and dollar asset holdings. Increases in risk aversion lead to capital flows that induce a depreciation of high-commodity currencies against low-commodity ones and an appreciation of the dollar against the rest of the world. We estimate the resulting factor structure empirically and use it to discipline the model. Our results indicate substantial heterogeneity in exchange rate drivers across countries, primarily determined by risk exposure. Riskier currencies are those of high-commodity countries that are most affected by the global business cycle and low-dollar countries that are most affected by shocks to the dollar value originating in the US. Currencies of countries combining both risk exposures are mostly driven by financial shocks. Currencies of countries with low risk exposures move less relative to the dollar, and their fluctuations are mostly determined by idiosyncratic shocks.
I develop a heterogeneous-country model of the world economy with global financial intermediaries. Imperfect risk-sharing creates a wealth distribution across countries. Risk-off shocks make the intermediaries revise their models of returns, which leads to repricing of country risk and triggers aggregate capital flight. In these events, the risk premia rise steeply in poor countries, while rich countries experience “retrenchment”: local agents use their external assets to replace foreign investors and stabilize asset prices. Risky assets in rich countries endogenously become safe havens. I derive asset price responses to global shocks in closed form and show that accounting for gross capital flows is crucial for explaining the international cross-section of asset returns. The wealth gradient in the cross-section of asset price responses identifies real and financial shocks behind the global financial cycle. A simple two-factor regression implied by the model explains 57% of the variation in the global cross-section of equities.
I build a tractable general equilibrium framework with investors operating under stochastic value-at-risk constraints. Constraints can be regulatory or self-imposed, originating in robustness concerns: intermediaries choose alternative models of asset returns to proof their decisions against model misspecification. Economies with heterogeneous value-at-risk limits admit a form of aggregation. Asset prices and interest rates depend on the representative risk limit, which is the wealth-weighted average of individual risk limits. Wealth distribution dynamics depend on a single stochastic process: the forecast error in the representative misspecified model of the total market return chosen by robust agents. The framework nests both forces driving time-varying risk premia in the literature: shocks to risk-bearing capacity and redistribution between heterogeneous agents. I decompose risk premium dynamics into these two parts and show that risk limit shocks do not redistribute directly, only changing investors’ leverage, which then determines how output shocks affect the wealth distribution.
This paper studies capital misallocation in a tractable model with random fixed costs of adjustment. We identify the distribution of fixed costs and productivity shocks using the entire size distribution and frequency of investments and provide an efficient estimation method. We derive the measure of capital misallocation in the presence of fixed costs and show that it differs from the traditional metric based on the variance of marginal product of capital. The key feature of models with lumpy investments responsible for this is their non-linearity: the distribution of marginal product of capital is not log-normal even with normal shocks and non-degenerate even when shocks are small. We apply our method to 40 years of panel data on Italian firms and find misallocation costs about 0.5-2% of output. Fixed costs contribute about one half to traditional measures of TFPR dispersion, putting an upper bound on potential inefficiencies.