arXiv subjects

Carsten Källner

Publications and source records attributed to Carsten Källner.

5 recordsLinked to original sources

arXiv2026

Students using GenAI lag behind in problem-solving competence: an agent-based study of classroom networks

The development of problem-solving competence (PSC) among high school students is foundational for preparing resilient and adaptive citizens. Generative artificial intelligence (GenAI) can support this process, but it may also encourage students to offload part of the cognitive work that is necessary for deep learning. While the individual effects of GenAI use are increasingly studied, its collective consequences for competence development within classroom environments remain underexplored. In this study, we use an agent-based model to simulate the evolution of PSC in a high school physics classroom, where students complete tasks individually, in collaboration with peers, or with the support of GenAI. By comparing classrooms with and without access to GenAI across different peer-network structures, we show that GenAI use can diminish competence development and increase the share of students remaining in lower competence tiers. These results suggest that the educational impact of GenAI should be assessed not only through individual learning outcomes but also through its effects on collective competence dynamics.

physics.soc-ph↗

arXiv2026

Who burdens the welfare state? Migration and ageing in housing, education, and healthcare demand

Political discourse attributes the pressure on European welfare systems to foreign nationals. Yet projections of service demand rarely disaggregate service demand by citizenship status. We develop a structural demographic model and project healthcare, education, and housing demand in Austria through 2050, disaggregated by citizenship status and regions across migration scenarios. We find that migration, ageing, and fertility shape each sector differently. In healthcare, the ageing of Austrian nationals contributes 4.7 times more to demand growth than immigration, with the most acute pressures in rural, low-migration regions. In housing, migration accounts for the entire net growth in demand, concentrated in metropolitan hubs. In education, aggregate demand contracts regardless of migration assumptions, whereas future needs are driven more by the births of foreigners in Austria than by new arrivals. Foreign nationals consume services in proportion to their demographic weight, with deviations explained by age structure rather than over-utilisation. These results show that the drivers of service demand are sector-specific: migration restrictions could ease housing pressure, but would not address ageing-driven healthcare demand and may accelerate contraction in the education system.

physics.soc-ph↗

arXiv2025

Migrants as First Responders: A Global Estimate of Disaster-Driven Remittances

International remittances represent a vital source of disaster adaptation finance for households around the world, yet their responsiveness to environmental disasters remains poorly quantified. We reveal a previously unmeasured global macro-financial system of international migrant diasporas remittances response to the occurrence of disasters in the country of origin. We do so by developing a structural model simulating individual remittance decisions, calibrated with global disaster records and bilateral monthly remittances flow data from the period 2010-2019. Our analysis reveals that approximately 332 billion USD (5.46\% of total remittances) were mobilized specifically in response to earthquakes, floods, storms, and droughts over the decade. Earthquakes triggered the largest remittance responses per person affected, while droughts elicited the smallest. The model also identifies significant variation in diaspora groups' capacity to activate financial support. These findings establish remittances as a substantial yet limited form of disaster finance, highlighting their importance and limitations in building resilience against future environmental shocks.

econ.GN↗

arXiv2025

Arriving Young, Leaving Old(er): Age-Structured International Migration on Subnational Scale in Austria

Modelling migration is complicated, as people move for many reasons. Some leave their country for the first time, others return to places they once called home, or move on to new destinations. However, most models focus only on who arrives, missing the full picture of how migrant populations evolve. We introduce a model for diaspora flows that estimates both arrivals and exits using daily migration flow rates, disaggregated by age and nationality. Drawing on high-resolution administrative data from Austria covering over 1.8 million foreign nationals, the model allocates these movements across more than 2,000 municipalities based on the size of local diaspora communities. We find that exits are not exceptions but a consistent and predictable feature across all groups. Migration rejuvenates Austria's population, as both arriving and departing migrants are younger than the average resident. This effect has distinct age-geography patterns: younger migrants are drawn to cities, while older migrants are more evenly distributed in the country. By capturing both arrivals and exits simultaneously, our approach provides a more comprehensive and interpretable picture of migration dynamics, how populations change over time, and how they are influenced by space, age, and national origins.

physics.soc-ph↗

arXiv2025

Refugees' path to legal stability is long and systematically unequal

Legal systems shape not only the recognition of migrants and refugees but also the pace and stability of their integration. Refugees often shift between multiple legal classifications, a process we refer to as the "legal journey". This journey is frequently prolonged and uncertain. Using a network-based approach, we analyze legal transitions for over 350,000 migrants in Austria (2022 to 2024). Refugees face highly unequal pathways to stability, ranging from two months for Ukrainians to nine months for Syrians and 20 months for Afghans. Women, especially from these regions, are more likely to gain protection; Afghan men wait up to 30 months on average. We also find that those who cross the border without going through official border controls face higher exit rates and lower chances of securing stable status. We show that legal integration is not a uniform process, but one structured by institutional design, procedural entry points, and unequal timelines.

physics.soc-ph↗