Working Papers

• Experience Effects and Technology Adoption: Evidence from Aortic Valve Replacement, November 2022. [new version coming soon]

Job Market Paper

Abstract: There have been concerted efforts in the medical profession to centralize certain surgical procedures in hopes that patients can benefit from treatment at hospitals with extensive experience or recent practice. In 2012, the Centers for Medicare and Medicaid Services (CMS) introduced minimum volume requirements that hospitals must satisfy to receive reimbursement for a new surgical procedure, transcatheter aortic valve replacement (TAVR). I examine the desirability of this regulation and the trade-offs that CMS faces between enhanced learning-by-doing, reduced patient access to hospitals offering TAVR, and fixed adoption costs. Using Medicare claims data, I find that doubling hospital experience reduces TAVR in-hospital mortality by one-sixth. I then develop and estimate a dynamic industry equilibrium model with learning-by-doing, patient choice, and hospital TAVR adoption. Counterfactual simulation shows that removing the policy restriction would have increased adoptions at hospitals that are relatively less desirable to patients. Further, this small access gain would be offset by reduced learning-by-doing and higher mortality. Overall, relative to the free-adoption counterfactual, the current Medicare policy achieves the same technology utilization and total consumer welfare with 13% lower fixed costs, thus improving social welfare.

• O-Ring Production Networks (with Banu Demir, Cecilia Fieler, and Daniel Xu), March 2023.

Accepted, Journal of Political Economy

Abstract: Using data from Turkish firms, we document a strong assortative matching of skills in the production network. A firm-specific export demand shock from a rich country increases the firm's skill intensity and shifts the firm toward skill-intensive domestic partners. We explain these patterns with a quantitative model with heterogeneous firms, endogenous quality choices, and network formation.  In the estimated model, high-quality firms are skill intensive and trade more with other high-quality firms. An economy-wide export demand shock of 5 percent induces exporters and non-exporters to upgrade quality, raising the average wage by 1.2 percent.  This effect is about nine times the effect in a special case of the model with no interconnection of quality choices. We use the model to study export promotion policies and the conditions for their success.

Publications

• Private Equity Acquisition and Responsiveness to Service-Line Profitability at Short-Term Acute Care Hospitals

(with Marcelo Cerullo, Anaeze C. Offodile II, Ryan McDevitt, and James Roberts), Health Affairs, 40(11), 2021.

• Association Between Hospital Private Equity Acquisition and Outcomes of Acute Medical Conditions Among Medicare Beneficiaries

(with Marcelo Cerullo, Karen Joynt Maddox, Anaeze C. Offodile II, Ryan McDevitt, and James Roberts), JAMA Network Open, 5(4), 2022.

• What Happens When Private Equity Firms Buy Hospitals

(with Marcelo Cerullo, Karen Joynt Maddox, Anaeze C. Offodile II, Ryan McDevitt, and James Roberts), Harvard Business Review, March 20, 2023.

Teaching

Fuqua School of Business, Duke University

• Teaching Assistant, Health Care Markets (MBA), Spring 2021.

• Teaching Assistant, Empirical Analysis for Strategy (MSc), Winter 2021.

• Teaching Assistant, Managerial Economics (MSc), Fall 2020.

Department of Economics, Duke University

• Teaching Assistant, Applied Econometrics in Microeconomics (MA), Spring 2020.

Contact

Department of Economics, Duke University

213 Social Sciences Building, 419 Chapel Drive, Durham, NC 27708

Email:  kelly.kaili.yang@duke.edu