I’m Sonia Petrini, a PhD researcher in Sociology at the University of Lausanne, and member of the Swiss Centre of Expertise in Life Course Research (LIVES). I am part of the Liberal and Radical Equality of Opportunity (EQUALOPP) project, led by Michael Grätz.
My work lies at the intersection of social inequality, genetics, and political philosophy, focusing on the relevance of genetic and environmental differences for the understanding of inequality of opportunity.
The nature of my research is highly quantitative, mapping empirical findings on genetic and environmental influences to conceptually different notions of what constitutes inequality.
Trained in Data Science and Economics, I combine quantitative rigor with a sociological perspective to study fairness and and opportunity.
Before my PhD, I published in computational linguistics at the Polytechnic University of Catalunya in Barcelona, investigating the structure and efficiency of human language.
In doing research I support the integration of Data Science in the Social Sciences, by promoting engagement in best coding practices and the use of machine learning applications.
Beyond academia, I practice hand-balancing and acro-yoga, play the violin and the ukulele, and sing in a choir.
My work
Genetic and social factors interact in more complex ways than previously thought. Using data from the US and UK, I find that in high-SES families a higher polygenic index is less necessary but more sufficient for attainment. This study offers a new framework for understanding inequality and educational achievement.
Work in progress
PNAS Nexus
Michael Grätz, Sonia Petrini
2025
Are inequalities fair if they depend on genes? By using polygenic indices (PGIs) to measure natural talents, this study clarifies how much inequalities reflect social origins versus genetic differences, offering new insights into fairness and merit in modern societies.
Published
Glottometrics
Sonia Petrini, Ramon Ferrer-i-Cancho
2025
We propose a two-regime model to describe connections between words. The breakpoint between regimes is remarkably consistent across 20 languages, suggesting a universal cognitive limit on how many words humans can process at once—a “chunk-and-pass” mechanism shaping sentence structure worldwide.
Published
Glottometrics
Sonia Petrini, Antoni Casas-i-Muñoz, Jordi Cluet-i-Martinell, Mengxue Wang, Chris Bentz, Ramon Ferrer-i-Cancho
2023
More frequent words tend to be shorter. We show that this holds in written and spoken language across 46 languages and 14 families. We find systematic evidence of linguistic compression, suggesting that human languages optimize word length to minimize communication effort.
Published
2022
This is a visualization tool of spatial data collected by IUCN Red List (), concerning the endangerment of animals and plants belonging to the fresh waters systems, from 2000 on. IUCN is the world’s most comprehensive information source on the global extinction risk status of animal, fungus and plant species, you can support it at .
Report
2022
I built an AI system that can spot knee effusions in ultrasound images — a crucial sign of internal bleeding in people with hemophilia. Using an autoeconder based on reconstruction by impainting, the best model identifies pathological knees with over 93% recall. This approach could improve care for patients who can’t always see a specialist right away.
Report
Education
- 2020 – Bachelor’s in Economics and Management at the University of Milan
- 2022 – Master’s in Data Science and Economics at the University of Milan
- 2022–2023 – Research Assistant at the Quantitative, Mathematical, and Computational Linguistics group at the Polytechnic University of Catalunya
- 2023–present – Ongoing PhD in Sociology at the University of Lausanne, on the Liberal and Radical Equality of Opportunity (EQUALOPP) project, led by Michael Grätz
Activities
Conferences
- ECSR. University of Cologne, 2025.
- European Social Science Genetics Network IV. University of Bristol, 2025.
- ISA RC28. University of Milan, 2025.
- Keynote - LIVES & nccr – on the move International Conference. University of Geneva, 2024.
- ECSR. Pompeu Fabra University, 2024.
- ISA RC28. Brown University, 2024.
- European Social Science Genetics Network III. Erasmus University Rotterdam, 2024.
- 12th International Quantitative Linguistics Conference (QUALICO). University of Lausanne, 2023.
Teaching
Teacher Assistant on the Master’s course “International Comparison in Social Inequalities” (in French). February 2024 - ongoing.
Additional training
- Genomics for Social Scientists – Epigenetics. Michigan University, 2025.
- ECSR Spring School. Collegio Carlo Alberto, 2024.
- Using genetics to understand social structures. University of Oslo, 2024.
Organized Seminars
“Ctrl + R: refresh your coding”. University of Lausanne. Co-organized with Claire Mariano. September 2024 - ongoing.
Academic Exchange
- University of Oslo, Department of Sociology and Human Geography. September 2025 - ongoing.
- University of Oxford, Nuffield College. January 2025.
