Andreas Forø Tollefsen

• Vestby, Jonas; Schutte, Sebastian; Tollefsen, Andreas Forø & Buhaug, Halvard (2024). Societal determinants of flood-induced displacement. Proceedings of the National Academy of Sciences of the United States of America. ISSN 0027-8424. 121(3). doi: 10.1073/pnas.2206188120. Full text in Research Archive
• Bartusevicius, Henrikas; Van Leeuwen, Florian; Mazepus, Honorata; Laustsen, Lasse & Tollefsen, Andreas Forø (2023). Russia's attacks on civilians strengthen Ukrainian resistance. PNAS Nexus. ISSN 2752-6542. 2(12). doi: 10.1093/pnasnexus/pgad386. Full text in Research Archive
• Eklund, Lina; Theisen, Ole Magnus; Baumann, Matthias; Tollefsen, Andreas Forø; Kuemmerle, Tobias & Østergaard Nielsen, Jonas (2022). Societal drought vulnerability and the Syrian climate-conflict nexus are better explained by agriculture than meteorology. Communications Earth & Environment. ISSN 2662-4435. 3(1). doi: 10.1038/s43247-022-00405-w. Full text in Research Archive Show summary

  Droughts are often suspected to increase the risk of violent conflict through agricultural production shocks, and existing studies often explore these links through meteorological proxies. In Syria, an alleged agricultural collapse caused by drought is assumed to have contributed to increased migration and the conflict outbreak in 2011. Here we use satellite derived cropland and climate data to study land use dynamics in relation to drought and conflict in Syria. We show that claims of an agricultural collapse cannot be substantiated as croplands saw a fast recovery after the 2007–2009 drought. Our study highlights the importance of considering land-use dynamics for understanding linkages between meteorological droughts, agricultural impacts, migration and conflict. Furthermore, our results suggest that the influential drought-migration-conflict narrative for Syria needs to be reexamined, with implications for wider discussions of how climate change might alter conflict risk.

• Vestby, Jonas; Brandsch, Jürgen; Landsverk, Peder; Larsen, Vilde Bergstad & Tollefsen, Andreas Forø (2022). Predicting (de-)Escalation of Sub-National Violence Using Gradient Boosting: Does It Work? International Interactions. ISSN 0305-0629. doi: 10.1080/03050629.2022.2021198.
• Østby, Gudrun; Shemyakina, Olga; Tollefsen, Andreas Forø; Urdal, Henrik & Verpoorten, Marijke (2021). Public Health and Armed Conflict: Immunization in Times of Systemic Disruptions. Population and Development Review. ISSN 0098-7921. 47(4), p. 1143–1177. doi: 10.1111/padr.12450.
• Linke, Andrew & Tollefsen, Andreas Forø (2021). Environmental stress and agricultural landownership in Africa. Global Environmental Change. ISSN 0959-3780. 67. doi: 10.1016/j.gloenvcha.2021.102237.
• Østby, Gudrun; Urdal, Henrik; Tollefsen, Andreas Forø; Kotsadam, Andreas; Belbo, Ragnhild & M. Ormhaug, Christin (2018). Organized violence and institutional child delivery: Micro-level evidence from Sub-Saharan Africa, 1989–2014. Demography. ISSN 0070-3370. p. 1–22. doi: 10.1007/s13524-018-0685-4. Full text in Research Archive
• Tollefsen, Andreas Forø (2018). Experienced poverty and local conflict violence. Conflict Management and Peace Science. ISSN 0738-8942. 37(3), p. 323–349. doi: 10.1177/0738894217741618.
• Kotsadam, Andreas; Østby, Gudrun; Rustad, Siri Camilla Aas; Tollefsen, Andreas Forø & Urdal, Henrik (2018). Development aid and infant mortality. Micro-level evidence from Nigeria. World Development. ISSN 0305-750X. 105, p. 59–69. doi: 10.1016/j.worlddev.2017.12.022. Show summary

  While there is a vast literature studying the effects of official development aid (ODA) on economic growth, there are far fewer comparative studies addressing how aid affects health outcomes. Furthermore, while much attention has been paid to country-level effects of aid, there is a clear knowledge gap in the literature when it comes to systematic studies of aid effectiveness below the country-level. Addressing this gap, we undertake what we believe is the first systematic attempt to study how ODA affects infant mortality at the subnational level. We match new geographic aid data from the AidData on the precise location, type, and time frame of bilateral and multilateral aid projects in Nigeria with available georeferenced survey data from five Nigerian Demographic and Health Surveys. Using quasi-experimental approaches, with mother fixed-effects, we are able to control for a vast number of unobserved factors that may otherwise be spuriously correlated with both infant mortality and ODA. The results indicate very clearly that geographical proximity to active aid projects reduces infant mortality. Moreover, aid contributes to reduce systematic inter-group, or horizontal, inequalities in a setting where such differences loom large. In particular, we find that aid more effectively reduces infant mortality in less privileged groups like children of Muslim women, and children living in rural, and in Muslim-dominated areas. Finally, there is evidence that aid projects are established in areas that on average have lower infant mortality than non-aid locations, suggesting that there are biases resulting in aid not necessarily reaching those populations in greatest need.

• Haugen, Heidi Østbø & Tollefsen, Andreas Forø (2017). Samfunnsgeografiske metoder. In Jordhus-Lier, David Christoffer & Stokke, Kristian (Ed.), Samfunnsgeografi: En innføring. Cappelen Damm Akademisk. ISSN 9788202547752. p. 63–72.
• Wig, Tore & Tollefsen, Andreas Forø (2016). Local institutional quality and conflict violence in Africa. Political Geography. ISSN 0962-6298. 53, p. 30–42. doi: 10.1016/j.polgeo.2016.01.003.
• Tollefsen, Andreas Forø & Buhaug, Halvard (2015). Insurgency and Inaccessibility. International Studies Review. ISSN 1521-9488. 17(1), p. 6–25. doi: 10.1111/misr.12202. Show summary

  A widely held belief within policy and practice contends that rough terrain and other physical obstacles to power projection hinder public surveillance, lower counterinsurgency capability, and generally constitute an important facilitator of rebellion. Likewise, sociocultural exclusion and alienation from the core are widely assumed to increase latent conflict risk through their influence on identity formation and perception of collective grievances. However, there is no scientific consensus on the empirical strength or significance of such a relationship, and many quantitative studies fail to find a robust link between a country's geographical or ethno-demographic characteristics and its estimated conflict risk. This paper represents a first comprehensive evaluation of how physical and sociocultural inaccessibility relate to contemporary civil wars. Drawing on recent advances in geographic information systems and georeferenced indicators of terrain, settlement patterns, ethno-political status, and armed conflict, we put the purported causal relationship to empirical test. A statistical analysis of civil-conflict events across post-Cold War Africa gives considerable support to the proposed theoretical framework, revealing that the various dimensions of inaccessibility all exert significant and substantive effects on local conflict risk. We find weaker evidence for the notion of substitutability; the inaccessibility indicators largely retain their individual effects when included in the same regression model.

• Tollefsen, Andreas Forø (2013). PostGIS 2.0 og Raster. Kart og Plan. ISSN 0047-3278. 73(3), p. 159–164.
• Tollefsen, Andreas Forø; Strand, Håvard & Buhaug, Halvard (2012). PRIO-GRID: A unified spatial data structure. Journal of Peace Research. ISSN 0022-3433. 49(2), p. 363–374. doi: 10.1177/0022343311431287. Show summary

  Contributions to the quantitative civil war literature increasingly rely on geo-referenced data and disaggregated research designs. While this is a welcome trend, it necessitates geographic information systems (GIS) skills and imposes new challenges for data collection and analysis. So far, solutions to these challenges differ between studies, obstructing direct comparison of findings and hampering replication and extension of earlier work. This article presents a standardized structure for storing, manipulating, and analyzing high-resolution spatial data. PRIO-GRID is a vector grid network with a resolution of 0.5 x 0.5 decimal degrees, covering all terrestrial areas of the world. Gridded data comprise inherently apolitical entities; the grid cells are fixed in time and space, they are insensitive to political boundaries and developments, and they are completely exogenous to likely features of interest, such as civil war outbreak, ethnic settlement patterns, extreme weather events, or the spatial distribution of wealth. Moreover, unlike other disaggregated approaches, gridded data may be scaled up or down in a consistent manner by varying the resolution of the grid. The released dataset comes with cell-specific information on a large selection of political, economic, demographic, environmental, and conflict variables for all years, 1946–2008. A simple descriptive data assessment of population density and economic activity is offered to demonstrate how PRIO-GRID may be applied in quantitative social science research.

• Buhaug, Halvard; Skrede Gleditsch, Kristian; Holtermann, Helge; Østby, Gudrun & Tollefsen, Andreas Forø (2011). It's the Local Economy, Stupid! Geographic Wealth Dispersion and Conflict Outbreak Location. Journal of Conflict Resolution. ISSN 0022-0027. 55(5), p. 814–840. doi: 10.1177/0022002711408011. Show summary

  Income varies considerably within countries and the locations where conflicts emerge are rarely typical or representative for states at large. Yet, most research on conflict has only examined national income averages and neglected spatial variation. The authors argue that civil conflicts are more likely to erupt in areas with low absolute income, even if a country’s gross domestic product (GDP) per capita is not necessarily low, and in areas with large deviations from national averages. The authors test these hypotheses empirically using spatially disaggregated data on the location of conflict outbreaks and per capita income estimates. The authors find that areas with absolute poverty indeed see more outbreaks of conflict, and they find some evidence that inequality increases the risk of conflict. Subnational information can improve on conventional country-based measures and help our understanding of how local features and variation can give rise to mobilization and violence.

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• Gerring, John; Apfeld, Brendan; Wig, Tore & Tollefsen, Andreas Forø (2022). The Deep Roots of Modern Democracy. Cambridge University Press. ISBN 978-1-009-10037-3. 500 p.

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• Tollefsen, Andreas Forø & Erdal, Marta Bivand (2023). Staying Rather than Leaving? Displacement and Conflict-Exposure in Ukraine. PRIO Blogs.
• Marthinussen Gustavsen, Elin & Tollefsen, Andreas Forø (2018). Hvor ble det av FN-styrkene? Forsvarets forum. ISSN 0809-845X. 3.
• Marthinussen Gustavsen, Elin & Tollefsen, Andreas Forø (2017). Norske bidrag i internasjonale operasjoner.
• Marthinussen Gustavsen, Elin; Tollefsen, Andreas Forø & Eggereide, Bård (2017). Analysis and assessment through the use of opinion survey.
• Belbo, Ragnhild; Østby, Gudrun; Urdal, Henrik; Tollefsen, Andreas Forø; Kotsadam, Andreas & M. Ormhaug, Christin (2015). Armed conflict and maternal health care Micro-level evidence from Sub-Saharan Africa.
• Tollefsen, Andreas Forø (2011). Conflict Hot Spots: Emergence, Causes and Consequences. Journal of Peace Research. ISSN 0022-3433. 48(2), p. 262–262.
• Skramstad, Laila; Tollefsen, Andreas Forø & Buhaug, Halvard (2023). Migrant Exposure and Individual-Level Trust: First Impressions from a Systematic Literature Review. Peace Research Institute Oslo (PRIO). ISSN 978-82-343-0470-5. 2023(7).
• Erdal, Marta Bivand; Mjelva, Mathilde Bålsrud & Tollefsen, Andreas Forø (2023). Conflict-related determinants of migration. Peace Research Institute Oslo (PRIO).
• Vestby, Jonas; Tollefsen, Andreas Forø & Buhaug, Halvard (2022). Climate and International Migration Flows: A Sensitivity Analysis of Gravity Model Specifications. Institutt for fredsforskning.
• Stai, Nora Kristine; Rødningen, Ida; Olsson, Louise & Tollefsen, Andreas Forø (2021). Breaking Down Barriers for Norway’s Deployment of Military Women. Peace Research Institute Oslo (PRIO). ISSN 978-82-343-0187-2. 2021(1).
• Nagel, Robert; Nordås, Ragnhild; Østby, Gudrun; Rustad, Siri Camilla Aas & Tollefsen, Andreas Forø (2021). Children at Risk of Wartime Sexual Violence, 1990–2019. Peace Research Institute Oslo (PRIO). ISSN 978-82-343-0071-4. 2021(1). Show summary

  ​In 2019, approximately 72 million children were living in a conflict zone where one or more armed actors were reported to perpetrate sexual violence against children. By this metric of risk, we also find that the number of children at risk of wartime sexual violence has increased since the 1990s. This brief presents new subnational estimates of this risk to children for the period 1990–2019. The study this is based on was commissioned by Save the Children and generated by PRIO, based on a new update of the SVAC database.

• Østby, Gudrun; Rustad, Siri Camilla Aas & Tollefsen, Andreas Forø (2020). Children Affected by Armed Conflict, 1990–2019. Peace Research Institute Oslo (PRIO). ISSN 978-82-343-0163-6. 2020(6).
• Østby, Gudrun; Rustad, Siri Camilla Aas & Tollefsen, Andreas Forø (2020). Children Affected by Armed Conflict, 1990–2018. Peace Research Institute Oslo (PRIO). ISSN 978-82-343-0069-1. 2020(1).
• Methi, Fredrik & Tollefsen, Andreas Forø (2020). Heating Up the Dry Debate: A Sensitivity Analysis of Drought and Communal Conflict in Sub-Saharan Africa (1989–2014). Universitetet i Oslo.
• Rustad, Siri Camilla Aas; Tollefsen, Andreas Forø & Gates, Scott (2019). The Fall and Rise of the Islamic State (IS). Peace Research Institute Oslo (PRIO). ISSN 978-82-7288-994-3. 2019(4).
• Østby, Gudrun; Rustad, Siri Camilla Aas & Tollefsen, Andreas Forø (2018). Children Affected by Armed Conflict, 1990–2017. Peace Research Institute Oslo (PRIO). ISSN 978-82-7288-913-4. 2018(10).
• Østby, Gudrun; Urdal, Henrik; Tollefsen, Andreas Forø; Kotsadam, Andreas; Belbo, Ragnhild & M. Ormhaug, Christin (2018). How Does Organized Violence Affect the Chances of Giving Birth at a Health Facility? Peace Research Institute Oslo (PRIO). ISSN 978-82-7288-892-2. 2018(8).
• Kotsadam, Andreas; Østby, Gudrun; Rustad, Siri Camilla Aas; Tollefsen, Andreas Forø & Urdal, Henrik (2018). Does Aid Reduce Infant Mortality? Local-Level Evidence from Nigeria. Peace Research Institute Oslo (PRIO). ISSN 978-82-7288-856-4. 2018(2).
• Tollefsen, Andreas Forø & Marthinussen Gustavsen, Elin (2017). Norway and UN Peacekeeping Trends. Peace Research Institute Oslo (PRIO). ISSN 978-82-7288-824-3. 2017(5).

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