Andreas Bjerre-Nielsen @andbjn.bsky.social · 09/10/2026As more powerful technologies, especially AI, enter classrooms and homes, rigorous experiments only become more urgent. We must study what these technologies do to learning, attention and well-being. Many thanks to funders, RAs and fantastic co-authors, Alp and Pradeep! 030
Andreas Bjerre-Nielsen @andbjn.bsky.social · 09/10/2026We find that academic performance improved (0.073 SD), with the largest gains among the weakest students. And students who experienced the ban became more supportive of it. www.science.org/doi/10.1126/...science.orgPhones impede learning: Evidence from a massive phone-free classroom experimentLower-performing students benefited the most, but even higher-performing students expressed support for the policy 140
Andreas Bjerre-Nielsen @andbjn.bsky.social · 09/10/2026Our large-scale study of phone bans just came out in Science. We randomized phone-free classrooms for 16,000+ students across 10 institutions in Odisha, India. Students deposited phones in a box at the start of each class, for a full semester. 184
Andreas Bjerre-Nielsen @andbjn.bsky.social · 17/01/2026🚀 Postdoc in School Choice & Admissions Join our research team at Uni Copenhagen with @gandil.bsky.social, Neilson & Oosterbeek. Work with unique high-resolution admissions data, long-run outcomes, and a large-scale field experiment. 📅 Apply by Feb 8 candidate.hr-manager.net/ApplicationI...candidate.hr-manager.net Talentech - Postdoctoral Position in School Choice Modeling and Simulation 1914
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/202511/ The work was led by Jolien Cremers, Benjamin Kohler, Benjamin F. Maier and done in collaboration with Stine N. Eriksen, Johanna Einsiedler, Frederik K. Christensen, @sunelehmann.com, David D. Lassen, Laust Hvas Mortensen. We are grateful for funding by the Villum Foundation. 010
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/202510/ We build on earlier work by @drtomemery.bsky.social and colleagues, who constructed the Dutch administrative network 🇳🇱. Our network adds temporal depth and enables computationally scalable analysis at the national level. 110
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20259/ This dataset opens new doors for research on: – Inequality & opportunity – Social cohesion – Spatial structure – Peer effects …all grounded in real, registry-based, population-wide data. 120
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20258/ To handle 1.4 billion ties, we used a bipartite network representation — linking individuals to shared foci like workplaces, schools, or households. This reduced edge count by up to 98%, making large-scale analysis feasible. 100
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20257/ Social connectivity is highly unequal: The top 20% of individuals hold nearly half the ties in some layers. Over time, the well-connected in one layer become central in others too — interlayer centrality accumulates. 111
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20256/ 📍 Geography matters. People are much more likely to be socially connected if they live nearby. Probability of connection drops steeply after 100m — confirming that spatial proximity underpins social proximity. 101
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20255/ By combining and weighting layers, we uncover a familiar pattern: The average shortest path is around 6 — echoing the “six degrees of separation” concept. But only when accounting for the structure and strength of ties. 101
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20254/ Social network position reflects income: Higher-income individuals tend to have more ties — especially when past ties are included. The more central you are, the higher you tend to be in the income distribution. 101
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20253/ We find that social ties persist and resurface — former classmates become neighbors, colleagues become family. Connections across life stages create dense, overlapping social paths. 112
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20252/ We mapped social ties through five layers: 👨👩👧 Family 🏠 Households 📍 Neighborhoods 🎓 Classmates 💼 Colleagues …across 2008–2021. The result is a dynamic, multiplex network of the entire population. 100
Andreas Bjerre-Nielsen @andbjn.bsky.social · 29/07/20251/ What does the social fabric of an entire country look like? We built a nation-scale social network of Denmark — 7.2 million people, 1.4 billion ties, 14 years of data. Here’s what we found 👇 📄 doi.org/10.1038/s415... #NetworkScience #Sociologydoi.orgUnveiling the social fabric through a temporal, nation-scale social network and its characteristics - Scientific ReportsScientific Reports - Unveiling the social fabric through a temporal, nation-scale social network and its characteristics 12513
Reposted by Andreas Bjerre-NielsenTereza Blazkova @terezablazek.bsky.social · 21/07/2025While human behavior and the data describing it evolve over time, fairness is often evaluated at a single snapshot. Yet, as we show in our newly published paper, fairness is dynamic. We studied how fairness evolves in dropout prediction across enrollment and found that it shifts over time. 142
Andreas Bjerre-Nielsen @andbjn.bsky.social · 23/07/2025Can AI interviewers match humans in qualitative interviews? We found: 🤖 AI asked more questions, yielding longer interviews 🧠 Responses to specific questions were longer in human-led interviews 📏 But response quality—specificity & relevance—was similar See more below 👇osf.ioOSF 020