What I do

I’m the head of data at Our World in Data (OWID), a scientific online publication that focuses on large global problems such as poverty, disease, hunger, climate change, war, existential risks, and inequality. Our goal is to make the research and data on these big problems accessible and understandable. Find out more about OWID and our mission.

My 45-minute conversation with Ivan Stegic on the TEN7 podcast is a very good overview of my background, the work of our team at OWID, and the principles we follow to make research and data more understandable and accessible.

I’m also a member of the effective altruism community. Effective altruism is a research field which uses high-quality evidence and careful reasoning to work out how to help others as much as possible. If you want to learn more, I recommend this article and this presentation. I also gave a talk at Effective Altruism Global London 2022, on the lessons I learned from the pandemic on how to present big ideas and complex data to the public.

I took the Giving What We Can Pledge in 2018. Since then, I’ve donated 10% of my yearly income to organizations that can most effectively use it to improve the lives of others.


Since 2020 · Our World in Data · Head of Data

2018–2021 · Five Books · Interviewer

2018–2020 · Neoxia · Lead Data Scientist

2019–2020 · OpenClassrooms · Data Science Mentor

2015–2018 · University of Oxford · Data Analyst/Scientist

2012–2015 · La Netscouade · Social Media Analyst

2011–2012 · Europe Ecology–The Greens · Social Media Manager


2011–2013 · Sciences Po Paris · Master’s degree in market research

2008–2011 · Sciences Po Paris · Bachelor’s degree in the humanities and social sciences


Jul. 2022 · Five key findings from the 2022 UN Population Prospects []

Jun. 2022 · Monkeypox Data Explorer []

Mar. 2022 · Commit to transparent COVID data until the WHO declares the pandemic is over. Nature 602, 549 (2022). []

Jan. 2022 · How do key COVID-19 metrics compare to previous waves? []

Nov. 2021 · How do death rates from COVID-19 differ between people who are vaccinated and those who are not? []

Sep. 2021 · Which countries are on track to reach global COVID-19 vaccination targets? []

May 2021 · Mathieu, E., Ritchie, H., Ortiz-Ospina, E. et al. A global database of COVID-19 vaccinations. Nature Human Behaviour 5, 947–953 (2021). []

Jan. 2021 · State-by-state data on COVID-19 vaccinations in the United States []

Dec. 2020 · Statistics and Research: Coronavirus (COVID-19) Vaccinations []

Nov. 2020 · Why do COVID-19 deaths in Sweden’s official data always appear to decrease? []

Oct. 2020 · Hasell, J., Mathieu, E., Beltekian, D. et al. A cross-country database of COVID-19 testing. Nature Scientific Data 7, 345 (2020). []

Apr. 2020 · Statistics and Research: Coronavirus (COVID-19) Testing []

Apr. 2020 · le Signal et le Bruit, a newsletter dedicated to questions relating to data and artificial intelligence [, in French]

Mar. 2020 · The best books on Historical Change and Economic Ideology, recommended by Thomas Piketty []

Jul. 2019 · The best books on Learning Python and Data Science, recommended by Vicki Boykis []

Jun. 2019 · Gibson LM, Nolan J, Littlejohns TJ, Mathieu E, Garratt S, Doherty N, et al. (2019) Factors associated with potentially serious incidental findings and with serious final diagnoses on multi-modal imaging in the UK Biobank Imaging Study: A prospective cohort study. PLoS ONE 14(6): e0218267. []

Apr. 2019 · Lay-Flurrie, S., Mathieu, E., Bankhead, C. et al. Patient consultation rate and clinical and NHS outcomes: a cross-sectional analysis of English primary care data from 2.7 million patients in 238 practices. BMC Health Services Research 19, 219 (2019). []

Mar. 2019 · Big data: are we witnessing the emergence of “full-stack” data expertise? [, in French]

Jan. 2019 · The best books on Effective Altruism, recommended by Will MacAskill []

Oct. 2018 · The best books on Data Science, recommended by Roger D. Peng []

Sep. 2018 · The best books on Existential Risks, recommended by The Centre for the Study of Existential Risk []

Sep. 2018 · The best modern Japanese literature, recommended by Linda Flores []

Aug. 2018 · The best books on Computer Science for Data Scientists, with Hadley Wickham []

Apr. 2018 · The best books on Computer Science and Programming, with Ana Bell []