Roman Merga | Economics

I am an Economist at IMF's Research Department. I received my PhD in Economics from the University of Rochester.

My main research interests focus in International Economics and Macroeconomics.

University of Rochester

Principles of Economics

(Undergraduate) Summer 2020: Instructor


(Graduate) Fall 2018, 2019, 2020: Teaching Assistant

Money, Credit and Banking

(Undergraduate) Spring 2019: Teaching Assistant

Pricing Policies

(Graduate) Fall 2018, 2019: Teaching Assistant (Simon Business school)

Intermediate Macroeconomics

(Undergraduate) Spring 2018: Teaching Assistant


Working papers

International Trade, Volatility, and Income Differences

I present a unified theory that explains two puzzles in international economics: (1) the negative relationship between aggregate firm-level sales volatility and total trade and (2) the limited participation of developing economies in international trade. The model integrates variable demand elasticity, domestic economic volatility, and exporters' investments in foreign markets into the standard model of international trade with heterogeneous firms. The presence of variable price elasticity reverses the ``Oi-Hartman-Abel" effect present in standard frameworks, making the expected losses during downturns outweigh boom-time gains. This discourages firms in volatile economies from entering and expanding into foreign markets, reducing aggregate exports and total income. The model's predictions align with macro and micro-level data, explaining nearly two-thirds of the unexplained variation in export differences between developed and developing countries and around 75% of the negative relationship between firm sales volatility and exports.

Real Exchange Rate Uncertainty Matters

Using a new time-varying measure of real exchange rate uncertainty, I find a negative relation between real exchange rate uncertainty and international trade at the aggregate level. Then, using Colombian firm-level data, I document 3 firm-level facts consistent with a precautionary margin in international trade. When real exchange rate uncertainty increases, exporters 1) reduce their export intensity, 2) are more likely to stop exporting, and 3) are less likely to start exporting to new markets. Additionally, I find that this behavior is mostly explained by those exporters paying higher interest rates and facing higher shipping lags. These results contrast with the predictions from standard international trade sunk cost models. Consequently, these models will underestimate the effects of real exchange uncertainty on international trade flows. I incorporate firm-level debt default and international shipping lag into a standard dynamic trade model to overcome this issue. In the new model, an increase in the real exchange rate uncertainty increases the probability that exporters end up financially vulnerable. To hedge against this risk, exporters respond by increasing mark-ups or quitting the export market, generating a drop in aggregate exports through both the intensive and the extensive margin of trade. Once this extension is calibrated to match firm-level Colombian data, it predicts that a one standard deviation increase in the real exchange rate uncertainty generates a drop in total exports of around 6%.

Fighting Income Inequality With International Trade
(with Victor Hernandez and Nicholas Kozeniauskas)

How does international trade affect the wage distribution across workers? We use detailed employer-employee covering 1987 to 2004 to answer this question. Using a new instrumental variable approach to disentangle the effects that trade openness has over the distribution of income and wages, we document that an increase in local trade exposure reduces wage inequality. Furthermore, we show that this result is associated with changes happening at the within-industry and within-firm levels. These changes lead to increases in the relative demand for low-wage and low-skill type of worker. At the within-industry level, we show that trade openness reallocates workers towards small firms and low-skilled jobs. At the within-firm level, we find that small firms increase their labor intensity and the average amount of workers, while larger firms reduce it in response to changes in trade openness. We argue that these firm-level responses are the root of the increase in the relative demand for low-wage workers.

Selected work in progress

Pricing to Clients and the Pass-Through of Shocks
(with Armen Khederlarian)

Most of the studies on exporter's pricing behavior focus on discrimination across markets. Less attention has been paid to how firms price discriminate across their portfolio of customers. Using novel firm-to-firm transaction level data from Colombian exports, we document three facts. First, price dispersion at the seller-product level is non-negligible and a large fraction of it is accounted for by within destination variation. Second, clients with larger shares in the exporters' past revenues pay lower prices and their prices are adjusted more frequently. Third, prices paid by the largest clients are less sensitive to fluctuations in the exchange rate, especially when the currency appreciates. These results illustrate that firms actively price discriminate across their buyers and offer more favorable terms to their largest clients. We rationalize these facts with a model of heterogeneous buyers and sellers, costly search, random matching and menu costs.