In the modern world, alien rulers are generally perceived to lack legitimacy. Political legitimacy is important because it is thought to be the principal alternative to coercive institutions. Little empirical evidence supports these claims, however. We devise a laboratory experiment that isolates alienness from other ruler characteristics. The experiment tests whether alien rulers have less legitimacy than native rulers, and whether the ability to punish compensates for this disadvantage. Using American and Israeli college student samples, we find that alien rulers receive less compliance than native rulers, and that the ability to punish does not allow alien rulers to "catch-up" with native rulers.

Although past scholarship shows that group inequalities in economic and political power (“Horizontal Inequalities”) correlate with dissent, violence, and civil wars, there is no direct empirical test of the perceptual explanation for this relationship at the individual level. Such explanation is vital to understanding how integration, inclusion in power-sharing agreements, and exclusion from political power filter down to mass publics. Moreover, subjective perceptions of group conditions do not always correspond to objective group realities. We hypothesize subjective perceptions attenuate the effect of objective exclusion on support for violence in ethnically divided societies. Cross-national comparative multilevel analyses of the 2005/6 Afrobarometer dataset (N = 19,278) confirm that subjective perceptions both amplify the effect of exclusion on acceptance of violence and alter the readiness of included groups to dissent. These findings carry implications for research, state-building, and conflict management.

Scholars agree that young men carry out most acts of political violence. Still, there is no consensus on the link between relatively large youth cohorts and the onset of violent, armed intra-state conflicts. In this paper, we examine the effect of youth bulge, a measure of the relative abundance of youth in a country, on the onset of two different types of civil wars—ethnic and non-ethnic wars. Building on and extending three datasets used by other scholars, we theoretically argue and empirically substantiate that, as a result of the negative effects of youth bulge on the economic conditions of the youth cohorts in the country, youth bulge affects the onset of non-ethnic wars, but not the onset of ethnic wars. Possible implications and directions for further research are then suggested.

Recent research has highlighted combat's positive effects for political behavior, but it is unclear whether they extend to attitudes toward the conflict itself. We exploit the assignment of health rankings determining combat eligibility in the  Israel Defense Forces to examine the effect of combat exposure on support for peaceful conflict resolution. Given the centrality of the Israeli-Palestinian conflict to global affairs, and its apparent intractability, the political consequences of combat become all the more pressing. We find that exposure to combat hardens attitudes toward the rival and reduces support for negotiation and compromise. Importantly, these attitudes translate into voting behavior: combatants are likely to vote for more hawkish parties. These findings call for caution in emphasizing the benign effects of combat and underscore the importance of reintegrating combatants during the transition from conflict to peace.

How does segregation shape intergroup violence in contested urban spaces? Should nominal rivals be kept separate or instead more closely integrated? We develop an empirically grounded agent-based model to understand the sources and patterns of violence in urban areas, employing Jerusalem as a demonstration case and seeding our model with microlevel, geocoded data on settlement patterns. An optimal set of parameters is selected to best fit the observed spatial distribution of violence in the city, with the calibrated model used to assess how different levels of segregation, reflecting various proposed virtual futures for Jerusalem, would shape violence. Our results suggest that besides spatial proximity, social distance is key to explaining conflict over urban areas: arrangements conducive to reducing the extent of intergroup interactionsincluding localized segregation, limits on mobility and migration, partition, and differentiation of political authoritycan be expected to dampen violence, although their effect depends decisively on social distance.

Intrastate conflicts, such as civil wars and ethnic confrontations, are the predominant form of organized violence in the world today. But internal strife can destabilize entire regions, drawing in people living beyond state borders-particularly those who share ideology, ethnicity, or kinship with one of the groups involved. These nonstate actors may not take part in formal armies or political parties, but they can play a significant role in the conflict. For example, when foreign volunteers forge alliances with domestic groups, they tend to attract other foreign interventions and may incite the state to centralize its power. Diasporan populations, depending on their connection to their homeland, might engage politically with financial support or overt aggression, either exacerbating or mitigating the conflict.  Nonstate Actors in Intrastate Conflicts takes an interdisciplinary approach to understanding the ways external individuals and groups become entangled with volatile states and how they influence the outcome of hostilities within a country's borders. Editors Dan Miodownik and Oren Barak bring together top scholars to examine case studies in Afghanistan, Lebanon, Israel/Palestine, and Turkey and explore the manifold roles of external nonstate actors. By shedding light on these overlooked participants whose causes and consequences can turn the tide of war, Nonstate Actors in Intrastate Conflicts provides a critical new perspective on the development and neutralization of civil war and ethnic violence.  Contributors: Oren Barak, Chanan Cohen, Robert A. Fitchette, Orit Gazit, Gallia Lindenstrauss, Nava Löwenheim, David Malet, Dan Miodownik, Maayan Mor, Avraham Sela, Gabriel (Gabi) Sheffer, Omer Yair.

Using an agent-based computational framework designed to explore the incidence of conflict between two nominally rival ethnic groups, we demonstrate that the impact of ethnic minority rule on civil war onset could be more nuanced than posited in the literature. By testing the effects of three key moderating variables on ethnic minority rule, our analysis demonstrates that: (i) when ethnicity is assumed to be salient for all individuals, conflict onset increases with size of the minority in power, although when salience is permitted to vary, onset decreases as minority and majority approach parity; (ii) fiscal policy-the spending and investment decisions of the minority EGIP-moderates conflict; conflict decreases when leaders make sound decisions, increases under corrupt regimes, and peaks under ethno-nationalist regimes that place a premium on territorial conquest; and lastly (iii) natural resources-their type and distribution-affect the level of conflict which is lowest in agrarian economies, higher in the presence of lootable resources, and still higher when lootable resource are ``diffuse''. Our analysis generates a set of propositions to be tested empirically, subject to data availability.

In examining both macro- and micro-level approaches to the study of civil war, this chapter considers scholarship in each of these traditions that either regards or disregards ethnicity as an essential explanation for violence. Given the voluminous literature on the subject, a select set of theories is reviewed: opportunity-based aggregate level arguments which address the causes of violence in non-ethnic civil wars; cross-national studies that evaluate the role of ethnicity using measures of fractionalization and polarization, as well as more recent configurational approaches that explicitly account for power differentials among politically relevant ethnic groups; micro-level approaches that analyze the dynamics of rebel recruitment, retention, and support, as well as the role that information, monitoring, and control play in the selective targeting of civilians; and disaggregated theories that explore the endogenous relationship between violence, ethnicity, and individual behavior. The chapter concludes with a brief review of existing macro-level datasets, as well as more recent efforts to build micro-level datasets that hold promise for bridging the macro-micro divide. © 2011 by Nova Science Publishers, Inc. All rights reserved.

This article extends the formal logic of Stathis Kalyvas' theory of selective violence to account for three political actors with asymmetric capabilities. In contrast to Kalyvas' theory, the authors' computer simulation suggests that (1) selective violence by the stronger actor will be concentrated in areas where weaker actors exercise control; (2) the relative level of selective violence used by weaker actors will be lower because of a reduced capacity to induce civilian collaboration; and (3) areas of parity among the three actors will exhibit low levels of selective violence perpetrated primarily by the strongest actor. Results from a logistic regression, using empirical data on Israel and two rival Palestinian factions from 2006 to 2008, are consistent with these predictions: Israel was more likely to use selective violence in areas largely controlled by Palestinian factions; zones of incomplete Israeli control were not prone to selective violence; and zones of mixed control witnessed moderate levels of selective violence, mainly by Israel. Nonetheless, Palestinian violence remained consistent with Kalyvas' predictions.

What explains the use of selective and indiscriminate violence in Israel, the West Bank, and Gaza from 1987 to 2005? Using micro-level data, an aggregated analysis indicates that areas of dominant but incomplete territorial control consistently experience more frequent and intense episodes of selective violence, providing support for Stathis Kalyvas's theory on the logic of civil violence. Disaggregating the analysis by each zone of control and perpetrator, however, offers only mixed empirical support for Kalyvas's predictions. While Palestinian-perpetrated violence is still consistent with theoretical expectations, Israel more frequently resorts to the use of selective violence where Palestinians exercise greater control. Such disconfirming evidence points to causal mechanisms previously unaccounted for and contributes to a more nuanced specification of the microfoundations of violence in civil conflict.

This article has two primary objectives: (i) to replicate an agent-based model of social interaction by Bhavnani (2003), in which the author explicitly specifies mechanisms underpinning Robert Putnam's (1993) work on Civic Traditions in Modern Italy, bridging the gap between the study's historical starting point-political regimes that characterized 14th Century Italy-and contemporary levels of social capitaloreflected in a `civic' North and an `un-civic' South; and (ii) to extend the original analysis, using a landscape of Italy that accounts for population density. The replication exercise is performed by different authors using an entirely distinct ABM toolkit (PS-I) with its own rule set governing agent-interaction and cultural change. The extension, which more closely approximates a docking exercise, utilizes equal area cartograms otherwise known as density-equalizing maps (Gastner and Newman 2004) to resize the territory according to 1993 population estimates. Our results indicate that: (i) using the criterion of distributional equivalence, we experience mixed success in replicating the original model given our inability to restrict the selection of partners to `eligible' neighbors and limit the number of agent interactions in a timestep; (ii) increasing the number of agents and introducing more realistic population distributions in our extension of the replication model increases distributional equivalence; (iii) using the weaker criteria of relational alignment, both the replication model and its extension capture the basic relationship between institutional effectiveness and civic change, the effect of open boundaries, historical shocks, and path dependence; and (iv) that replication and docking may be usefully combined in model-to-model analysis, with an eye towards verification, reimplementation, and alignment.

This article presents the results of an experiment that attempted the reconciliation of opposite expectations regarding the effectiveness of political decentralization on ethno-political mobilization. An agent-based model was run thousands of times to explore the effect of decentralization. The experiments suggest that the impact is nonlinear: weak and medium levels of decentralization increase the likelihood of ethno-political mobilization, while strong decentralization decreases it. The explanation derives from how minority control of political institutions affects the dynamic of minority identity ascription and the realization of the goal or the frustration of ethnic members seeking more complete political dominance of the regional ideational space.

Violence can take place along a multitude of cleavages, e.g., (1) between political groups like the Kach Movement, pitting West Bank settlers against Israeli governments supporting the land-for-peace agenda; (2) between religious groups, such as Christians and Muslims in the Nigerian cities of Jos and Kaduna; (3) along class lines, as in India between Dalits and members of the Brahminical upper castes, upwardly mobile intermediate castes, and even other backward castes such as the Thevars; and (4) between ethnic groups such as the Hutu and Tutsi, both within and across state boundaries in Rwanda and neighboring Burundi. © 2010 Springer Science + Business Media, LLC.

In this paper we consider the uses political scientists have made of agent-based modeling (ABM) and the challenges associated with designing research at differing levels of complexity. We propose a typology of ABM research designs-investigating abstractions, testing theories comprised of ensembles of simple variables, or implementing virtualizations of complex situations. Our illustrations are drawn from work done on problems pertaining to the evolution of collective identities and norms and to their contribution to collective action. By increasing the visibility of research design questions and clarifying the choices and opportunities associated with them, we seek to expand the scope of responsible methodological uses of ABM techniques and render the increasing variety of that work accessible to wider audiences.

This article examines how the relationship between ethnic polarization and civil war could be moderated by different degrees of ethnic salience. Using an agent-based computational model, we analyze the polarization-conflict relationship when ethnic salience is ``fixed''-high for every member of two nominally rival ethnic groups and ``variable''-permitted to vary across individuals as a function of relative income. We find that (1) when salience is fixed, conflict onset is twice as high at low levels of polarization compared to when salience is permitted to vary, with the difference decreasing at high levels of polarization; (2) the relationship between conflict onset and the range over which we calculate variable salience is positive and robust for low and moderate levels of polarization; (3) the relationship between polarization and conflict onset is robust even under minority domination, if one holds salience fixed; and (4) holding ethnic salience fixed effectively amplifies the negative effect of polarization on economic performance.

The emergence of an ever-widening sphere of global public policy is a new reality in a world characterized by the blurring of boundaries between the national and the global; by flows of ideas, people, and commodities; and by new global risks and opportunities. In this context, this article explores the empirical puzzle of the sudden outbreak of reforms leading to central-bank independence. How can we best understand the outbreak of reforms in the 1990s? It is suggested here that the reforms were diffused in a contagious and uncoordinated manner in a global policy process that may best be captured by Kingdon's policy stream model. We develop an agent-based model to evaluate the effects of three little-explored aspects of the diffusion process. These are (i) the likelihood of the outbreak of reform, (ii) the rate of adoption of the reform, and (iii) the time to outbreak. We find that the likelihood of outbreak depends on the saliency of a problem, in conjunction with the length of time that a problem has been on the public agenda. We also find that an increase in the size of the environment surveyed before a decision is made increases the rate of adoption but also the time to outbreak. The more global the information available for agents, the longer is the time to outbreak, but outbreaks unfold much faster.

This research note provides a general introduction to REsCape: an agent-based computational framework for studying the relationship between natural resources, ethnicity, and civil war. By permitting the user to specify: (i) different resource profiles ranging from a purely agrarian economy to one based on the artisanal or industrial extraction of alluvial or kimberlite diamonds; (ii) different patterns of ethnic domination, ethnic polarization, and varying degrees of ethnic salience; as well as (iii) specific modes of play for key agents, the framework can be used to assess the effects of key variables - whether taken in isolation or in various combinations - on the onset and duration of civil war. Our objective is to make REsCape available as an open source toolkit in the future, one that can be used, modified, and refined by students and scholars of civil war.

Explanations of the emergence of regional autonomy movements - political organizations seeking to express sub-state affinities and interests - often highlight cultural differences and economic incentives as important reasons driving regional elites and local politicians to form such organization and explain the support regional autonomy movements receive. In this paper I employ a specialized agent-based computer simulation as a laboratory for `thought experiments' to evaluate alternative theoretical expectations of the independent and combined consequences of regional economic and cultural circumstances on the likelihood of regional mobilization. The simulations suggest that pronounced cultural differences and strong economic incentives contribute to the emergence of three independent yet related aspects of autonomy mobilization: the emergence of political boundaries, minority support, and minority clustering. Furthermore, these experiment indicate that the impact of cultural differences on the emergence of political boundaries may be contingent on the strength of the economic incentives, and visa versa.

In this article we revisit the notion of territoriality, suggesting that such a focus, rather than electability, increases the universe of cases available, differentiates between these and other state-wide parties, and reveals variation between ethnoregional parties competing for support in arguably the same political space. We conclude that scholars of ethnoregional politics need to apply broadly accepted understandings of the centrality of territoriality to both case-selection criteria and dimensions of "relevance" studied in order to better understand this distinct and growing political phenomenon. Copyright © Taylor & Francis Group, LLC.

Institutional frameworks powerfully determine the goals, violence, and trajectories of identitarian movements-including secessionist movements. However, both small-N and large-N researchers disagree on the question of whether ``power-sharing'' arrangements, instead of repression, are more or less likely to mitigate threats of secessionist mobilizations by disaffected, regionally concentrated minority groups. The PS-I modeling platform was used to create a virtual country ``Beita,'' containing within it a disaffected, partially controlled, regionally concentrated minority. Drawing on constructivist identity theory to determine behaviors by individual agents in Beita, the most popular theoretical positions on this issue were tested. Data were drawn from batches of hundreds of Beita histories produced under rigorous experimental conditions. The results lend support to sophisticated interpretations of the effects of repression vs. responsive or representative types of power-sharing. Although in the short run repression works to suppress ethnopolitical mobilization, it does not effectively reduce the threat of secession. Power-sharing can be more effective, but it also tends to encourage larger minority identitarian movements.