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Clionadh Raleigh, Roudabeh Kishi, and Andrew Linke recently compared their own Armed Conflict Location and Events Dataset (ACLED) to three other conflict event datasets in Humanities & Social Sciences Communications. In this article, we investigate their claims about what drives differences between the two researcher led projects the Uppsala Conflict Data Program (UCDP) and ACLED. In the process, we address some general issues that arise in event data collection, including the importance of stable definitions, how demands on sourcing varies with the type of data collected, and how strategies for dealing with uncertainty and ambiguity impact the data. Contrary to the claims made in the target article, the differences between ACLED and UCDP in the cases put forth by the authors are not primarily due to differences in sourcing or inclusion thresholds. Analyzing the same cases, we show that most of the differences are due to auxiliary coding rules, standards for source evaluation and misrepresentations of UCDP data in the original article.

In the target article Clionadh Raleigh, Roudabeh Kishi, and Andrew Linke set out to assess the validity and reliability of four conflict event datasets. To accomplish this would require a plausible reference data that at least approximates ground truth. Lacking this, the authors use their own Armed Conflict Location and Events Dataset (ACLED) as the baseline for comparison. A comparative evaluation of datasets could in principle bring to light differences, and perhaps identify strengths and weaknesses of the different datasets. It could help us improve and develop better data generation processes over time, and also provide a better understanding the limits of existing conflict event data so that it is used appropriately. However, the evaluation and analysis provided by the authors is based on false premises and mired by misrepresentations, factual errors and conceptual misunderstandings, to a degree that it becomes misleading rather than enlightening. In this paper I detail how the evaluation and analysis provided in the target article is based a factually false premise and mired by misrepresentations, factual errors and conceptual misunderstandings.

This article examines global trends in organized violence based on new data from the Uppsala Conflict Data Program (UCDP). In 2024, the number of state-based armed conflicts rose from 59 to 61, marking the second consecutive year in which the UCDP recorded a historically high number of conflicts. The number of wars increased from nine to 11, the highest count since 2016. The UCDP recorded marginal declines in both state-based fatalities and organized violence as a whole. In contrast, one-sided violence saw a sharp increase, driven primarily by escalating attacks by Islamic State in Africa and widespread killings by non-state actors in Haiti. Non-state conflict declined, both in the number of active conflicts and in total fatalities. In total, the UCDP recorded almost 160,000 deaths in organized violence in 2024. The article also addresses challenges in the classification of casualties, highlighting how limitations in data quality and information access contribute to uncertainty around the civilian-to-combatant fatality ratio. These challenges are particularly acute in cases of organized crime violence, in which the distinction between civilians and combatants is often blurred, and in which indiscriminate types of warfare, such as artillery and aerial bombardment, are used in urban settings.

This article examines trends in organized violence based on new data from the Uppsala Conflict Data Program (UCDP). In 2023, fatalities from organized violence decreased for the first time since the rapid increase observed in 2020, dropping from 310,000 in 2022 to 154,000 in 2023. Despite this decline, these figures represent some of the highest fatality rates recorded since the Rwandan genocide in 1994, surpassed only by those of 2022 and 2021. The decrease was primarily attributed to the end of the conflict in Ethiopia's Tigray region, which accounted for about 60% of battle-related deaths in both 2022 and 2021. Despite this positive development, the number of active state-based armed conflicts increased by three in 2023, reaching the highest level ever recorded by the UCDP, totaling 59. Non-state conflicts and one-sided violence decreased in 2023 when compared to 2022, evident in both the reduction of the active conflicts/actors and the decrease in fatalities attributed to these forms of violence. However, despite this overall decrease, fatalities resulting from non-state conflicts remained at historically high levels in 2023. Analysis of non-state conflict data spanning the past decade reveals that it comprises the ten most violent years on record. Organized crime groups have predominantly fueled this escalation. Unlike rebel groups, organized crime groups typically lack political goals and are primarily motivated by economic gain. Conflicts between these groups tend to intensify around drug smuggling routes and in urban areas, driven by shifts in alliances and leadership dynamics among the actors.

This article reports on trends in organized violence, building on new data from the Uppsala Conflict Data Program (UCDP). In 2022, fatalities from organized violence increased by a staggering 97%, compared to the previous year, from 120,000 in 2021 to 237,000 in 2022, making 2022 the deadliest year since the Rwandan genocide in 1994. The increase was driven by two, particularly deadly, state-based armed conflicts: the Russia-Ukraine war, and the war in Ethiopia against TPLF (Tigray People's Liberation Front). With more than 81,500 and 101,000 fatalities respectively, these are the two most deadly state-based conflict-years recorded in the post-1989 period. The Russian invasion of Ukraine is the first large-scale interstate war in 20 years, and the first interstate armed conflict since World War II where a major power in the international system seeks both territorial gains for itself and the subjugation of another state through regime change. We have witnessed an emerging trend of increased conflict between states in the last decade, including cases where major powers support opposite sides in internationalized intrastate conflict. UCDP recorded 55 active state-based armed conflicts in 2022, an increase of one compared to the previous year. Eight of these conflicts reached the level of war. While the fatalities caused by non-state conflict decreased somewhat when compared to 2021, the number of non-state conflicts, as well as both the number of civilians killed in one-sided violence and the number of actors carrying out such violence, increased in 2022.

This article reports on trends in organized violence, building on new data by the Uppsala Conflict Data Program (UCDP). The falling trend in fatalities stemming from organized violence in the world, observed between 2014 and 2019, was decisively reversed in 2021 as fatalities increased significantly. UCDP registered more than 119,100 deaths in organized violence in 2021, a 46% increase from the previous year. The increase was largely driven by escalating conflicts in Afghanistan, Ethiopia, and Yemen. Fatalities increased in all three categories of organized violence, despite a decrease in the number of active state-based conflicts, as well as the number of actors carrying out one-sided violence against civilians. UCDP recorded 54 state-based conflicts in 2021, a decrease by two compared to the previous year. Five of the conflicts were active at the intensity of war, the lowest number of wars since 2010. Violence in 2021 was thus concentrated to fewer but bloodier conflicts. Unmanned aerial vehicles (UAVs), commonly known as drones, have become increasingly important features of modern conflicts, and the trend in their usage is discussed in the special feature section. UAV usage has since 2019 dispersed among a significant larger number of actors, even as the downscaling in the involvement of the United States in the war on terror has led to a decrease in drone-related fatalities.

This article reports on trends in organized violence, building on new data by the Uppsala Conflict Data Program (UCDP). The falling trend in fatalities stemming from organized violence in the world, observed for five consecutive years, broke upwards in 2020 and deaths in organized violence seem to have settled on a high plateau. UCDP registered more than 80,100 deaths in organized violence in 2020, compared to 76,300 in 2019. The decrease in violence in Afghanistan and Syria was countered by escalating conflicts in, for example, Artsakh (Nagorno-Karabakh), Azerbaijan and Tigray, Ethiopia. Moreover, the call for a global ceasefire following the outbreak of the COVID-19 pandemic failed to produce any results. In fact, the number of active state-based and non-state conflicts, as well as the number of actors carrying out one-sided violence against civilians, increased when compared to 2019. UCDP noted a record-high number of 56 state-based conflicts in 2020, including eight wars. Most of the conflicts occurred in Africa, as the region registered 30 state-based conflicts, including nine new or restarted ones.

How does war shape human altruism? Some find warfare increases generosity within groups only. Others maintain that war’s prosocial effects extend to outgroup members as well. To make sense of these disparate findings, we offer a theoretical framework that highlights the role of threat sensitivity in altruism. Refugees from Syria and Iraq (N = 1521) completed a welfare tradeoff task and threat perceptions scale where the other's group identity, gender and age were experimentally varied. We found that individuals belonging to social categories associated with more threat (outgroup members, males, and younger individuals) were afforded less altruism compared to individuals belonging to non-threatening social categories (ingroup members, females and the elderly). War exposure enhanced bias against threatening social categories through increased threat-sensitivity. Our results have implications for understanding how warfare shapes altruism and welfare tradeoffs in light of cross-cutting social categories and for policies promoting post-conflict cooperation.

This article reports on trends in organized violence, building on new data by the Uppsala Conflict Data Program (UCDP). The defeat of Islamic State (IS) in Syria and Iraq has pushed the number of fatalities, almost 75,600, to its lowest level since the outbreak of the Syrian civil war in 2011. However, this de-escalation in Syria is countered by increased violence in Africa, as IS and other transnational jihadist groups have relocated their efforts there. Furthermore, violence has continued to increase in Afghanistan; UCDP recorded more than 31,200 fatalities in Afghanistan in 2019, which accounts for 40% of all fatalities from organized violence across the globe. The general decline in fatalities from organized violence does not correspond with the trend in the number of active conflicts, which remained on a historically high level. UCDP recorded 54 state-based conflicts in 2019, including seven wars. Twenty-eight state-based conflicts involved IS (Islamic State), al-Qaida or their affiliates. In the past decade, conflicts involving these transnational jihadist groups have driven many of the trends in organized violence.