107 research outputs found

    VICToRy: Visual Interactive Consistency Management in Tolerant Rule-based Systems

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    In the field of Model-Driven Engineering, there exist numerous tools that support various consistency management operations including model transformation, synchronisation and consistency checking. The supported operations, however, typically run completely in the background with only input and output made visible to the user. We argue that this often reduces both understandability and controllability. As a step towards improving this situation, we present VICToRy, a debugger for model generation and transformation based on Triple Graph Grammars, a well-known rule-based approach to bidirectional transformation. In addition to a fine-grained, step-by-step, interactive visualisation, VICToRy enables the user to actively explore and choose between multiple valid rule applications thus improving control and understanding.Comment: In Proceedings GCM 2020, arXiv:2012.0118

    Horizontal Inequalities and Ethnonationalist Civil War: A Global Comparison

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    Contemporary research on civil war has largely dismissed the role of political and economic grievances, focusing instead on opportunities for conflict. However, these strong claims rest on questionable theoretical and empirical grounds. Whereas scholars have examined primarily the relationship between individual inequality and conflict, we argue that horizontal inequalities between politically relevant ethnic groups and states at large can promote ethnonationalist conflict. Extending the empirical scope to the entire world, this article introduces a new spatial method that combines our newly geocoded data on ethnic groups' settlement areas with spatial wealth estimates. Based on these methodological advances, we find that, in highly unequal societies, both rich and poor groups fight more often than those groups whose wealth lies closer to the country average. Our results remain robust to a number of alternative sample definitions and specification

    The Geography of the International System: The CShapes Dataset

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    We describe CShapes, a new dataset that provides historical maps of state boundaries and capitals in the post-World War II period. The dataset is coded according to both the Correlates of War and the Gleditsch and Ward (1999) state lists, and is therefore compatible with a great number of existing databases in the discipline. Provided in a geographic data format, CShapes can be used directly with standard GIS software, allowing a wide range of spatial computations. In addition, we supply a CShapes package for the R statistical toolkit. This package enables researchers without GIS skills to perform various useful operations on the GIS maps. The paper introduces the CShapes dataset and structure and gives three examples of how to use CShapes in political science research. First, we show how results from quantitative analysis can be depicted intuitively as a map. The second application gives an example of computing indicators on the CShapes maps, which can then be used in statistical tests. Third, we illustrate the use of CShapes for generating different weights matrices in spatial statistical applications. All the examples can be replicated using the freely available R package and do not require specialized GIS skills. The dataset is available for download from the CShapes website (http://nils.weidmann.ws/projects/cshapes). © Taylor & Francis Group, LLC

    At Home and Abroad: The Use of Denial-of-service Attacks during Elections in Nondemocratic Regimes

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    In this article, we study the political use of denial-of-service (DoS) attacks, a particular form of cyberattack that disables web services by flooding them with high levels of data traffic. We argue that websites in nondemocratic regimes should be especially prone to this type of attack, particularly around political focal points such as elections. This is due to two mechanisms: governments employ DoS attacks to censor regime-threatening information, while at the same time, activists use DoS attacks as a tool to publicly undermine the government’s authority. We analyze these mechanisms by relying on measurements of DoS attacks based on large-scale Internet traffic data. Our results show that in authoritarian countries, elections indeed increase the number of DoS attacks. However, these attacks do not seem to be directed primarily against the country itself but rather against other states that serve as hosts for news websites from this country.publishe

    Horizontal Inequalities and Ethnonationalist Civil War: A Global Comparison

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    Contemporary research on civil war has largely dismissed the role of political and economic grievances, focusing instead on opportunities for conflict. However, these strong claims rest on questionable theoretical and empirical grounds. Whereas scholars have examined primarily the relationship between individual inequality and conflict, we argue that horizontal inequalities between politically relevant ethnic groups and states at large can promote ethnonationalist conflict. Extending the empirical scope to the entire world, this article introduces a new spatial method that combines our newly geocoded data on ethnic groups’ settlement areas with spatial wealth estimates. Based on these methodological advances, we find that, in highly unequal societies, both rich and poor groups fight more often than those groups whose wealth lies closer to the country average. Our results remain robust to a number of alternative sample definitions and specifications.</jats:p

    Mapping the International System, 1886-2019: The CShapes 2.0 Dataset

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    This article introduces CShapes 2.0, a GIS dataset that maps the borders of states and dependent territories from 1886 through 2019. Our dataset builds on the previous CShapes dataset and improves it in two ways. First, it extends temporal coverage from 1946 back to the year 1886, which followed the Berlin Conference on the partition of Africa. Second, the new dataset is no longer limited to independent states, but also maps the borders of colonies and other dependencies, thereby providing near complete global coverage of political units throughout recent history. This article explains the coding procedure, provides a preview of the dataset and presents three illustrative applications

    Fortune Favours the Bold: An Agent-Based Model Reveals Adaptive Advantages of Overconfidence in War

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    Overconfidence has long been considered a cause of war. Like other decision-making biases, overconfidence seems detrimental because it increases the frequency and costs of fighting. However, evolutionary biologists have proposed that overconfidence may also confer adaptive advantages: increasing ambition, resolve, persistence, bluffing opponents, and winning net payoffs from risky opportunities despite occasional failures. We report the results of an agent-based model of inter-state conflict, which allows us to evaluate the performance of different strategies in competition with each other. Counter-intuitively, we find that overconfident states predominate in the population at the expense of unbiased or underconfident states. Overconfident states win because: (1) they are more likely to accumulate resources from frequent attempts at conquest; (2) they are more likely to gang up on weak states, forcing victims to split their defences; and (3) when the decision threshold for attacking requires an overwhelming asymmetry of power, unbiased and underconfident states shirk many conflicts they are actually likely to win. These “adaptive advantages” of overconfidence may, via selection effects, learning, or evolved psychology, have spread and become entrenched among modern states, organizations and decision-makers. This would help to explain the frequent association of overconfidence and war, even if it no longer brings benefits today

    Aid on Demand: African Leaders and the Geography of China's Foreign Assistance

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    On the Accuracy of Media-based Conflict Event Data

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    Empirical researchers of civil war rarely collect data on violence themselves and instead rely on other sources of information. One frequently used source is media reports, which serve as the basis for many ongoing data projects in the discipline. However, news reports rarely cover a conflict comprehensively and objectively and may therefore be prone to various reporting issues. This article provides an analysis of the accuracy of information given in news reports. In particular, if focuses on two types of “hard facts” that event data sets require: the location of an event and its severity. By linking media reports to firsthand accounts from a military database, the article does two things: (1) it analyzes the determinants of inaccuracy and confirms the expectation that events with a low number of observers tend to have higher reporting inaccuracies and (2) it assesses the magnitude of these inaccuracies and the implications for conducting empirical analyses with media-based event data
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