Democratic Inefficiency? Regime Type and Suboptimal Choices in International Politics

This article examines the relationship between regime type and decision makers’ tendency to make suboptimal choices in international crises. To test hypotheses on the optimality of democratic foreign policy, the author uses a novel statistical measure of suboptimality in foreign policy behavior. This estimator builds on Signorino’s statistical strategic models to allow for actor-level variation in deviations from optimal behavior in a strategic setting. An analysis of the international disputes from 1919 to 1999 shows that democratic leaders have a greater tendency to choose policies not optimal for their citizens than do nondemocratic leaders.Governmen

Measuring Uncertainty in International Relations: Heteroskedastic Strategic Models

Actor-level variations in the amounts of uncertainty have been widely ignored in the growing literature on statistical models of strategic interaction in international relations. In this article, I provide a tool for testing theories about the level of uncertainty in strategic interactions. I show that ignoring potential variations in levels of uncertainty across different cases can be a source of bias for empirical analyses. I propose a method to incorporate this form of heteroskedasticity into existing estimators and show that this method can improve inferences. With a series of Monte Carlo experiments, I evaluate the magnitude and the severity of the bias and inconsistency in estimators that ignore heteroskedasticity. More importantly, the tools developed in this article have many interesting substantive application areas. Examples considered include measuring speculators’ suboptimal behavior tendencies in international currency crises, and capturing varying levels of signaling and Bayesian updating behavior in the recent strategic models of signaling.Governmen

Adverse selection and growth under IMF programs

The dominant approach to studying the effects of IMF programs has emphasized moral hazard, but we find that adverse selection has more impressive effects. We propose a novel strategic selection model to study the growth effects of IMF programs, which allows for the possibility of adverse selection. We find that adverse selection occurs: the countries that are most interested in participating in IMF programs are the least likely to have favorable growth outcomes. Controlling for this selection effect, we find that countries benefit from IMF programs on average in terms of higher growth rates, but that some countries benefit from participation, while others are harmed. Moral hazard predicts that long-term users of Fund resources benefit least from participating in programs, while adverse selection predicts the opposite. Contrary to previous findings, we find that IMF programs have more successful growth performance among long-term users than among short-term users.Governmen

How Uncertainty about War Outcomes Affects War Onset

In canonical accounts of war, conflict outcomes are inherently uncertain. Contesting literatures posit that this uncertainty, arising from stochastic elements of the war-fighting process, may induce conflict due to greater risks of miscalculation or foster peace by breeding caution. We theorize that states, on average, exhibit prudence when confronting greater uncertainty. Despite its conceptual importance, extant proxies for uncertainty at various levels of analysis—such as polarity, balance of power, system concentration, and dyadic relative capabilities—are imprecise and theoretically inappropriate indicators. To overcome this shortcoming, we theorize the conditions that elevate the magnitude of uncertainty over conflict outcomes and introduce a novel measure that captures this uncertainty within any k-state system. Through extensive empirical analysis, we confirm uncertainty’s pacifying effect and show how this effect operates at different levels of analysis.Governmen

Arms Diffusion and War

The authors present a model of the relationship between the spread of new military technologies and the occurrence of war. A new technology could shift the balance of power, causing anticipatory war as one side tries to prevent the other from obtaining it. When one side already has it, war is more likely when the shift in power is large, likely, and durable. When neither side has it, war is more likely when the expected shift is asymmetric (e.g., one side is more likely to get it) and when the two sides fear that a war will occur once one of them has it. The authors illustrate the model with historical examples from the spread of firearms (the Musket Wars in precolonial New Zealand) and of nuclear weapons (the end of US nuclear monopoly and the 1967 Six-Day War). A broader implication is that major power competition can unintentionally cause wars elsewhere.Governmen

The relationship between oxidative stress and coronary artery ectasia

Background: Whereas coronary artery ectasia (CAE) is a rare abnormality of the coronary arteries, co-existent coronary artery disease (CAD) is commonly seen in CAE patients. Since a causative relationship has been shown to exist between oxidative stress and CAD, we sought to determine whether any relationship exists between oxidative stress and CAE. Methods: Fourty four patients with CAE (without CAD) and 86 controls (without any coronary disease) were recruited from among 1,520 patients undergoing coronary angiography. CAE subgroups were determined in accordance with the Markis classification system. Mean values for serum total oxidant status (TOS), total antioxidant status (TAS) and the oxidative stress index (OSI) were statistically compared between these two study groups and among CAE subgroups, with p = 0.05 set as the threshold for statistical significance. Results: TOS and OSI were significantly increased (p = 0.018 and 0.0002) and TAS decreased (p = 0.031) in the CAE versus control group. TOS and TAS were independently related to CAE (p = 0.037 and 0.039), with an r2 of 0.127. Interestingly, however, among CAE subgroups, no differences were observed. Conclusions: Oxidative stress might be implicated in the pathogenesis of CAE. Clinically-defined CAE subgroups did not differ in terms of oxidative stress status. However, the clinical implications of these findings are unclear and warrant further investigation. (Cardiol J 2010; 17, 5: 488-494

Knowing one's future preferences: A correlated agent model with Bayesian updating

We generalize two classes of statistical sequential incomplete information games: (1) those resembling typical signaling games, in which a single agent represents each player, allowing for information to be revealed about future play; and (2) those in which each player is represented by a set of independent agents, where moves do not reveal private information. The generalized model we develop, the Correlated Agent Model, relies on a parameter, ρ, which denotes the correlation between two agents’ private information, i.e. the extent to which a player knows the future private component of her preferences. The independent agent and single agent models are special cases, where ρ=0 and ρ=1, respectively. The model also allows 0 < ρ < 1, a class of games which have not yet been considered. We apply the model to crisis bargaining and demonstrate how to estimate ρ, as well as parameters associated with utilities.Governmen

Structural insights into the loss of catalytic competence in pectate lyase activity at low pH

AbstractPectate lyase, a family 1 polysaccharide lyase, catalyses cleavage of the α-1,4 linkage of the polysaccharide homogalacturonan via an anti β-elimination reaction. In the Michaelis complex two calcium ions bind between the C6 carboxylate of the d-galacturonate residue and enzyme aspartates at the active centre (+1 subsite), they withdraw electrons acidifying the C5 proton facilitating its abstraction by the catalytic arginine. Here we show that activity is lost at low pH because protonation of aspartates results in the loss of the two catalytic calcium-ions causing a profound failure to correctly organise the Michaelis complex