Sevcan Yesiltas

Koç University
Department of Economics and Finance
Rumelifeneri Yolu 34450
Sariyer, Istanbul

Institutional Affiliation: Koç University

NBER Working Papers and Publications

May 2020COVID-19 and Emerging Markets: An Epidemiological Model with International Production Networks and Capital Flows
with Cem Çakmaklı, Selva Demiralp, Ṣebnem Kalemli-Özcan, Muhammed A. Yildirim: w27191
We quantify the macroeconomic effects of COVID-19 for emerging markets using a SIR-multisector-small open economy model and calibrating it to Turkey. Domestic infection rates feed into both sectoral supply and sectoral demand shocks. Sectoral demand shocks also incorporate lower external demand due to foreign infection rates. Infection rates change endogenously with different lockdown policies. To calibrate the model, we use indicators of physical proximity and tele-workability of jobs to measure supply shocks. We use real-time credit card purchases to pin down demand shocks. Our results show that the optimal policy, which yields the lowest economic cost and saves the maximum number of lives, can be achieved under a full lockdown of 39 days. Partial and/or no lockdowns have higher economic...
September 2015How to Construct Nationally Representative Firm Level Data from the Orbis Global Database: New Facts and Aggregate Implications
with Sebnem Kalemli-Ozcan, Bent Sorensen, Carolina Villegas-Sanchez, Vadym Volosovych: w21558
We construct representative firm-level longitudinal data for twenty-seven European countries using financial statements from the Orbis global database, providing a “how-to” guide on the construction. We validate our dataset by comparing its aggregate coverage to official statistics and present three new facts. First, smaller firms (SMEs) account for the largest share of economic activity. Second, industry concentration has increased among firms that report only consolidated statements, but decreased overall. Third, the increased concentration is accounted for by foreign-owned firms. Documenting these facts requires nationally representative data both in cross-sectional and time-series dimensions.
August 2011Leverage Across Firms, Banks, and Countries
with Sebnem Kalemli-Ozcan, Bent Sorensen: w17354
We present new stylized facts on bank and firm leverage for 2000-2009 using extensive internationally comparable micro level data from several countries. The main result is that there was very little buildup in leverage for the average non-financial firm and commercial bank before the crisis, but the picture was quite different for large commercial banks in the United States and for investment banks worldwide. We document the following patterns: a) there was an increase in leverage ratios of investment banks and financial firms during the early 2000s; b) there was no visible increase for commercial banks and non-financial firms; c) off balance-sheet items constitute a big fraction of assets, especially for large commercial banks in the United States; d) the leverage ratio is procyclical fo...

Published: Kalemli-Ozcan, Sebnem & Sorensen, Bent & Yesiltas, Sevcan, 2012. "Leverage across firms, banks, and countries," Journal of International Economics, Elsevier, vol. 88(2), pages 284-298. citation courtesy of

June 2011Leverage Across Firms, Banks and Countries
with Sebnem Kalemli-Ozcan, Bent Sorensen
in Global Financial Crisis, Charles Engel, Kristin Forbes, and Jeffrey Frankel, organizers
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