Li-Wei Chao is a Principal Researcher at the Centro de Economia e Finanças (CEF.UP), Faculty of Economics, University of Porto (Portugal). He is also a Research Affiliate of the Population Studies Center at the University of Pennsylvania (USA). He was formerly a Professor of Entrepreneurship at the Porto Business School (Portugal), an appointed expert in Health Economics at the U.S. Centers for Disease Control and Prevention, an Assistant Professor of Anesthesia and of Healthcare Systems at the University of Pennsylvania (USA), a Visiting Professor of Medicine at the University of Cape Town (South Africa), and an Honorary Research Associate at the Human Sciences Research Council (South Africa). He is the Principal Investigator (PI) of a project funded by the U.S. National Institutes of Health that examines entrepreneurship in townships in South Africa, the effect of poor health and HIV/AIDS on entrepreneurial entry, exit, and success, and the extent to which HIV-related stigma and discrimination differentially harms specific business sectors. He is also a recipient of an Advanced Grant and a Principal Researcher Grant from the Portuguese Foundation of Science and Technology. Dr. Chao received his M.D. from the University of Chicago Pritzker School of Medicine, and his Ph.D. in Managerial Economics from the Wharton School of Business at the University of Pennsylvania. His medical training provides him with an in-depth understanding of disease processes and biological basis of behavior, and his economics training equips him with tools and paradigms not traditional to population health research. This combination greatly facilitates his interdisciplinary research agenda. His PhD dissertation -- Pill vs. Condom: Lovers in Unity or Battle of the Sexes -- modeled contraceptive choices using separate male and female utility functions and compared the consensus models of household choice with those derived from simultaneous move Nash and female-leader Stackelberg as solution concepts. In recent years, he has implemented studies that used: (1) a computer program that tracks participant's scrolling behavior to detect eagerness to uncover other people's HIV status, (2) experimental economics games in rural Malawi and in urban South Africa to quantify filial relationships and HIV discrimination, (3) incentivized risk-taking and delay of gratification tasks to derive measures to predict sexual behavior, (4) fMRI to examine neural mechanisms of sacrifice for one's mother vs. a stranger, (5) biomarkers to predict work productivity potential, (5) vignette survey to measure taste-based and statistical discrimination of workers with HIV from both the employee and the employer perspectives, and (6) essential heterogeneity and marginal treatment effect to examine individual differences in the adoption of self-protection behavior.