Sebastián Castillo Ramos

I am a Postdoctoral Researcher in Public Economics at the University of Helsinki, funded by the Finnish Cultural Foundation. I am affiliated with the Finnish Centre of Excellence in Tax Systems Research (FIT) and the Welfare and Policy Analysis in Latin America and the Caribbean network (WAPLAC).

Research Interests

My research lies at the intersection of Public Economics and Labor Economics, with a focus on tax evasion, optimal tax policy design, and the behavioral responses of individuals and firms to fiscal incentives. A central question in my work is how evasion opportunities shape decisions beyond compliance itself — particularly occupational choices between wage employment and self-employment. Using quasi-experimental variation from tax reforms in Chile and survey data, I estimate structural parameters that inform both the theory and practice of tax enforcement.

On the theoretical side, I study optimal tax administration in environments where agents can misreport income or strategically manipulate verifiable data. In parallel, I study VAT compliance and firm behavior in developing economies, applying machine learning methods to administrative tax records.

More broadly, I am motivated by how fiscal institutions can be designed to improve economic efficiency and social welfare — a question relevant for both Europe and Latin America.

With colleagues at UNU-WIDER, I developed an open-access toolkit for tax gap estimation, available for use by tax authorities worldwide.

I hold a Ph.D. in Economics from Pontificia Universidad Católica de Chile (2022) and an M.A. (Summa Cum Laude) from Georgetown University/ILADES at Universidad Alberto Hurtado.

📩 sebastian.castillo@helsinki.fi | sebacastillo.ra@gmail.com