Predicting the decline of ethnic civil war: Was gurr right and for the right reasons?

© The Author(s) 2017. Many scholars have detected a decrease of political violence, but the causes of this decline remain unclear. As a contribution to this debate, we revisit the controversy over trends in conflict after the end of the Cold War. While many made ominous predictions of surging ethnic warfare, Gurr presented evidence of a pacifying trend since the mid-1990s and predicted a further decline in ethnic conflict in an article on ‘the waning of ethnic war’. Leveraging more recent data on ethnic groups and their participation in ethnic civil wars, this study evaluates if Gurr was right about the decline of ethnic conflict, and if he was right for the right reasons. We assess whether an increase in governments’ accommodative policies toward ethnic groups can plausibly account for a decline in ethnic civil war. Our findings lend considerable support to an account of the pacifying trend that stresses the granting of group rights, regional autonomy, and inclusion in power-sharing, as well as democratization and peacekeeping

The evolution of civil war severity, 1816-2005

© 2016 Walter de Gruyter GmbH, Berlin/Boston. Previous analyses of civil war trends tend to be informal and consider only post 1945 data. We examine data on civil wars over the period 1816-2005, using new methods for evolutionary growth processes. We find a number of new patterns and trends in civil war that have received little attention in previous research, including a structural break in frequency of conflict with decolonialization, as well as evidence of periodicity in civil conflict. We develop new measures of civil war intensity and impact, and find that conflicts have been generally more severe in the 20th than in the 19th century. We also find that the frequency-severity distribution of civil war does not appear to follow a power-law distribution, unlike data on many other types of conflict. Although structural trends suggest an increase in future civil wars, we discuss possible limiting factors that might prevent this in light of the recent observed decline in civil wars after the Cold War

Patterns of dominant flows in the world trade web

The large-scale organization of the world economies is exhibiting increasingly levels of local heterogeneity and global interdependency. Understanding the relation between local and global features calls for analytical tools able to uncover the global emerging organization of the international trade network. Here we analyze the world network of bilateral trade imbalances and characterize its overall flux organization, unraveling local and global high-flux pathways that define the backbone of the trade system. We develop a general procedure capable to progressively filter out in a consistent and quantitative way the dominant trade channels. This procedure is completely general and can be applied to any weighted network to detect the underlying structure of transport flows. The trade fluxes properties of the world trade web determines a ranking of trade partnerships that highlights global interdependencies, providing information not accessible by simple local analysis. The present work provides new quantitative tools for a dynamical approach to the propagation of economic crises

The Cultural Evolution of Democracy: Saltational Changes in A Political Regime Landscape

Transitions to democracy are most often considered the outcome of historical modernization processes. Socio-economic changes, such as increases in per capita GNP, education levels, urbanization and communication, have traditionally been found to be correlates or ‘requisites’ of democratic reform. However, transition times and the number of reform steps have not been studied comprehensively. Here we show that historically, transitions to democracy have mainly occurred through rapid leaps rather than slow and incremental transition steps, with a median time from autocracy to democracy of 2.4 years, and overnight in the reverse direction. Our results show that autocracy and democracy have acted as peaks in an evolutionary landscape of possible modes of institutional arrangements. Only scarcely have there been slow incremental transitions. We discuss our results in relation to the application of phylogenetic comparative methods in cultural evolution and point out that the evolving unit in this system is the institutional arrangement, not the individual country which is instead better regarded as the ‘host’ for the political system

Jan Tinbergen’s Legacy for Economic Networks: From the Gravity Model to Quantum Statistics

Jan Tinbergen, the first recipient of the Nobel Memorial Prize in Economics in 1969, obtained his PhD in physics at the University of Leiden under the supervision of Paul Ehrenfest in 1929. Among many achievements as an economist after his training as a physicist, Tinbergen proposed the so-called Gravity Model of international trade. The model predicts that the intensity of trade between two countries is described by a formula similar to Newton's law of gravitation, where mass is replaced by Gross Domestic Product. Since Tinbergen's proposal, the Gravity Model has become the standard model of non-zero trade flows in macroeconomics. However, its intrinsic limitation is the prediction of a completely connected network, which fails to explain the observed intricate topology of international trade. Recent network models overcome this limitation by describing the real network as a member of a maximum-entropy statistical ensemble. The resulting expressions are formally analogous to quantum statistics: the international trade network is found to closely follow the Fermi-Dirac statistics in its purely binary topology, and the recently proposed mixed Bose-Fermi statistics in its full (binary plus weighted) structure. This seemingly esoteric result is actually a simple effect of the heterogeneity of world countries, that imposes strong structural constraints on the network. Our discussion highlights similarities and differences between macroeconomics and statistical-physics approaches to economic networks

Saving Human Lives: What Complexity Science and Information Systems can Contribute

We discuss models and data of crowd disasters, crime, terrorism, war and disease spreading to show that conventional recipes, such as deterrence strategies, are often not effective and sufficient to contain them. Many common approaches do not provide a good picture of the actual system behavior, because they neglect feedback loops, instabilities and cascade effects. The complex and often counter-intuitive behavior of social systems and their macro-level collective dynamics can be better understood by means of complexity science. We highlight that a suitable system design and management can help to stop undesirable cascade effects and to enable favorable kinds of self-organization in the system. In such a way, complexity science can help to save human lives.Comment: 67 pages, 25 figures; accepted for publication in Journal of Statistical Physics [for related work see http://www.futurict.eu/