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Replication package
rbstgrid package (co-developed with Johan A. Dornschneider-Elkink)
This methodological note makes two novel contributions to spatial political and conflict research using grid data. First, it develops a methodological theory of how uncertainty specific to grid data affects inference. Second, it introduces a comprehensive robustness test on sensitivity to this uncertainty, implemented in R. The uncertainty stems from (1) establishing the correct size of grid cells, (2) deciding the correct locations where the dividing lines of grid data are drawn, and (3) a greater effect of measurement errors due to finer grid cells. The proposed test diversifies grid cell sizes, by aggregating original grid cells into a multiple of these grid cells. The test also varies the locations of the diving lines, by using different starting points of grid cell aggregation (e.g., starting the aggregation from the corner of the entire map or one grid cell of the original size away from the corner). I apply the test to Theisen et al. (Int. Secur. 36(3):79-106, 2011), who utilize the PRIO-GRID data (Tollefsen et al., J. Peace Res. 49(2):363-374, 2012), to substantiate its use.
Open access
Supplemental materials
bayesdtm package
How should we evaluate the effect of a policy on the likelihood of an undesirable event, such as conflict? The significance test has three limitations. First, relying on statistical significance misses the fact that uncertainty is a continuous scale. Second, focusing on a standard point estimate overlooks the variation in plausible effect sizes. Third, the criterion of substantive significance is rarely explained or justified. A new Bayesian decision-theoretic model, "causal binary loss function model," overcomes these issues. It compares the expected loss under a policy intervention with the one under no intervention. These losses are computed based on a particular range of the effect sizes of a policy, the probability mass of this effect size range, the cost of the policy, and the cost of the undesirable event the policy intends to address. The model is more applicable than common statistical decision-theoretic models using the standard loss functions or capturing costs in terms of false positives and false negatives. I exemplify the model's use through three applications and provide an R package.
Supplemental material
Accepted Manuscript version
How do different degrees of displaced people's hardship shape their expectations of peace and violence in post-conflict societies? We develop a novel explanation and empirically examine it using survey data collected in Bosnia Herzegovina in 2013. The displaced may suffer by being the target of the hostility of opposing groups and/or by receiving little support from, or being mistreated by, their own groups and international actors. As a result, they develop negative opinions about these actors, friend and foe alike, become pessimistic about the possibility of cooperation, and see post-conflict peace as unsustainable. We find those who have suffered greater hardship during displacement are more likely to foresee political violence. Hardship during displacement is also a stronger predictor than the experience of violence. Our analysis implies that, while violence does have an impact as suggested by the literature, other hardship during displacement, such as the lack of support, also matters.
Replication package
Accepted Manuscript version
How does leadership's desire for political survival in ethnically heterogeneous democracies affect the probability of states exchanging nationalist foreign policy? I define nationalist foreign policy as foreign policy that aims to fulfil national self-governance using a civic or ethnic frame. I argue that civic-nationalist policy disputing the territoriality of one's own state is more likely, while ethno-nationalist policy favoring the leadership's foreign co-ethnics is less likely, when the size of the leadership's ethnic group is small and the level of democracy is relatively high. This is because the leadership, under such domestic conditions, has to mobilize support from other ethnic groups in order to stay in power. Civic-nationalist policy allows the leadership to increase domestic solidarity across ethnic lines and mobilize support from other ethnic groups, whereas ethno-nationalist policy would risk other ethnic groups criticizing the leadership of being ethno-centrist. These hypotheses are supported by quantitative analysis using an original dataset.
This book chapter discusses effects of presidential term limits on several political outcomes, reviewing the literature and empirically examining three hypotheses (the effects of presidential term limits on government expenditure, the probability of repression, and the probability of successful coercive diplomacy).
Why did Pakistan initiate the Kargil War with India, so soon after the two states reached overt nuclear status? Existing theories attribute war between nuclear states either to the strategic opportunities of limited conflict or to a closing opportunity of preventive war to destroy the nuclear capabilities of nuclearizing states. However, strategic opportunities explain the possibility of, but not the motivation for, war; after all, the nuclearization of India began long before the war. To develop a better explanation, I propose an original theory of how the theoretical mechanisms of nuclear deterrence can be altered by nationalist conflict. The Indo-Pakistani nationalist conflict not only motivated Pakistan to initiate the war because of its perception of a threat, but also caused both states to overestimate their own deterrence credibility and underestimate the other's capability and resolve to conduct war. These nationalist motivations and estimations enabled the war between the two nuclear states. The article suggests that nuclear weapons may have different effects on different types of conflict.
Open access
Replication package
Does the state of the domestic economy change the size of the effect of audience costs? As public opinion research has shown, citizens assess the performance of their leaders based not only on foreign policy, but also on the domestic economy. Thus, if leaders are subject to audience costs, they should be even less able to afford failure in an international crisis when the economy is performing badly than when the economy is doing well. As a result, such leaders should be even more able to make their threats credible and, therefore, are more likely to be successful in coercive diplomacy. This novel prediction finds no empirical support in a replication study using Moon and Souva (2016). I discuss possible reasons for this result and avenues for further research.
We examine and discuss the state of political science in Ireland, using a new dataset onarticles published in major domestic, European, and international academic journals byauthors affiliated with Irish institutions during the period 1999-2014. Our main findings areas follows: political scientists in Ireland have generally focused more on comparativepolitics and international relations than on methodology, political theory, or public policy.In terms of methods and authorship, however, there are some notable differences betweenarticles published in domestic, European, and international journals. Qualitative analysis and single case studies have been more commonly employed in national-level publications,while inferential quantitative analysis and large-N data have been more widely used ininternational-level articles. Gender balance in authorship is now more the norm in nationaljournals than in European and international journals. Finally, Irish political science hasundergone significant changes during the period examined. There have been increases inco-authoring and the use of inferential quantitative methods and large-N data which aretypically associated with the approaches taken in the major international journals ofpolitical science. In this regard, Irish political science has become more 'globalised'.
Are firms with female owners or managers less corrupt than other firms? We test this question using firm-level data on corruption, ownership, and management. We find that women in positions of influence are associated with less corruption: female owners are associated with a lower incidence of bribery and report smaller levels of bribery. Moreover, corruption is seen as less of an obstacle in companies where women are represented in top management. By providing evidence that women are associated with lower levels of corruption in business our research contributes to the literature on development, gender equality, and corruption.
Open access
Replication package
In the literature on nuclear proliferation, some argue that further proliferation decreases interstate conflict, some say that it increases interstate conflict, and others indicate a non-linear relationship between these two factors. However, there has been no systematic empirical investigation on the relationship between nuclear proliferation and a propensity for conflict at the interstate-systemic level. To fill this gap, the current paper uses the machine learning method Random Forests, which can investigate complex non-linear relationships between dependent and independent variables, and which can identify important regressors from a group of all potential regressors in explaining the relationship between nuclear proliferation and the propensity for conflict. The results indicate that, on average, a larger number of nuclear states decrease the systemic propensity for interstate conflict, while the emergence of new nuclear states does not have an important effect. This paper also notes, however, that scholars should investigate other risks of proliferation to assess whether nuclear proliferation is better or worse for international peace and security in general.
This article examines the causation and extent of interstate crisis escalation among two conflictual dyads, namely Greece-Turkey and India-Pakistan. It draws from the International Crisis Behaviour dataset to present a new sub-dataset of 12 interstate crises involving the two dyads in the period 1987 to 2002. While crisis behaviour in Greece-Turkey has frequently been analysed within the context of two major regional organizations (NATO and the EU), Indian-Pakistani crises have been studied within the perspective of nuclear proliferation. To examine the linkage between these features and interstate crises, the article operationalizes the security dilemma and the diversionary theory of war through a probabilistic model. Using Ragin's (2000) comparative qualitative analysis, it demonstrates that both the security dilemma and diversionary theory explain crisis escalation, although the latter covers more cases with a smaller margin of error. Moreover, the article demonstrates that Greek-Turkish crises have generally escalated to relatively low levels of conflict (threat of war or show of force), while Indian-Pakistani crises have spiralled to higher levels of confrontation (use of force). In both dyads, nuclear weapons and regional organizations have shaped the boundaries of possible escalatory action. The EU and NATO have contributed to mitigating crisis escalation and the use of force between the Aegean neighbours, while unintentionally encouraging low intensity confrontations; meanwhile, in South Asia, nuclear weapons in combination with fragile domestic regimes have exacerbated crises, particularly in the form of state-sponsored unconventional warfare.
This article argues that partition - a peacebuilding approach in a post-conflict society - can lead to the transformation of intrastate conflict to interstate conflict, thereby providing a helpful insight for further comparison of partition with multi-ethnic settlements such as federalism/powersharing and reconciliation. While advocates of partition maintain that intrastate conflict caused by a security dilemma between ethnic groups can be settled only by partition, this article argues that partition could cause the transformation of conflict rather than settling it. The cases of India-Pakistan and Cyprus provide the empirical evidence. The partition of India and Pakistan transformed intrastate conflict within India into interstate conflict between India and Pakistan including nuclear competition. The partition of Cyprus contributed to interstate conflict between Greece and Turkey. Therefore, this article concludes that the transformation of conflict reduces the value of partition, and that it is necessary to take this point into consideration when partition is compared with alternatives such as federalism/powersharing and reconciliation.
Supplemental document
Replication package
Which type of statistical uncertainty - statistical (in)significance with a p-value, or a Bayesian probability - enables people to see the continuous nature of uncertainty more clearly in a policymaking context? An original survey experiment used a hypothetical scenario, where participants from Ireland were asked whether to introduce a new bus line to reduce traffic jams, given a research report estimating its effectiveness. The treatments were uncertainty information: statistical significance with a p-value of 2%, statistical insignificance with a p-value of 25%, the 95% probability that the estimate is correct, and the 68% probability that the estimate is correct. In the case of lower uncertainty, both significance and Bayesian frameworks resulted in a large proportion of participants adopting the policy (0.82 and 0.91 respectively). In the case of higher uncertainty, the significance framework led a much smaller proportion of participants to adopt the policy (0.39 against 0.83). The findings suggest participants saw the continuous nature of uncertainty more clearly in the Bayesian framework than in the significance framework.
ccdfpost package
Replication code
How should social scientists understand and communicate the uncertainty of statistically estimated causal effects? I propose we utilize the posterior distribution of a causal effect and present the probability of the effect being greater (in absolute terms) than different minimum effect sizes. Probability is an intuitive measure of uncertainty for understanding and communication. In addition, the proposed approach needs no decision threshold for an uncertainty measure or an effect size, unlike the conventional approaches. I apply the proposed approach to a previous social scientific study, showing it enables richer inference than the significance-vs.-insignificance approach taken by the original study. The accompanying R package makes my approach easy to implement.
Truchlewski, Zbigniew, Akisato Suzuki, and Alexandru D. Moise. "'Yes, but What Is Your DAG?' Theory, Transparency, and Cumulative Knowledge in Political Science."