Rose McDermott

Decoherence in Josephson Qubits from Dielectric Loss

Dielectric loss from two-level states is shown to be a dominant decoherence source in superconducting quantum bits. Depending on the qubit design, dielectric loss from insulating materials or the tunnel junction can lead to short coherence times. We show that a variety of microwave and qubit measurements are well modeled by loss from resonant absorption of two-level defects. Our results demonstrate that this loss can be significantly reduced by using better dielectrics and fabricating junctions of small area . With a redesigned phase qubit employing low-loss dielectrics, the energy relaxation rate has been improved by a factor of 20, opening up the possibility of multiqubit gates and algorithms.

Identity as a Variable

As scholarly interest in the concept of identity continues to grow, social identities are proving to be crucially important for understanding contemporary life. Despite—or perhaps because of—the sprawl of different treatments of identity in the social sciences, the concept has remained too analytically loose to be as useful a tool as the literature’s early promise had suggested. We propose to solve this longstanding problem by developing the analytical rigor and methodological imagination that will make identity a more useful variable for the social sciences. This article offers more precision by defining collective identity as a social category that varies along two dimensions—content and contestation. Content describes the meaning of a collective identity. The content of social identities may take the form of four non-mutually-exclusive types: constitutive norms; social purposes; relational comparisons with other social categories; and cognitive models. Contestation refers to the degree of agreement within a group over the content of the shared category. Our conceptualization thus enables collective identities to be compared according to the agreement and disagreement about their meanings by the members of the group. The final section of the article looks at the methodology of identity scholarship. Addressing the wide array of methodological options on identity—including discourse analysis, surveys, and content analysis, as well as promising newer methods like experiments, agent-based modeling, and cognitive mapping—we hope to provide the kind of brush clearing that will enable the field to move forward methodologically as well.

Monoamine oxidase A gene (MAOA) predicts behavioral aggression following provocation

Monoamine oxidase A gene (MAOA) has earned the nickname “warrior gene” because it has been linked to aggression in observational and survey-based studies. However, no controlled experimental studies have tested whether the warrior gene actually drives behavioral manifestations of these tendencies. We report an experiment, synthesizing work in psychology and behavioral economics, which demonstrates that aggression occurs with greater intensity and frequency as provocation is experimentally manipulated upwards, especially among low activity MAOA (MAOA-L) subjects. In this study, subjects paid to punish those they believed had taken money from them by administering varying amounts of unpleasantly hot (spicy) sauce to their opponent. There is some evidence of a main effect for genotype and some evidence for a gene by environment interaction, such that MAOA is less associated with the occurrence of aggression in a low provocation condition, but significantly predicts such behavior in a high provocation situation. This new evidence for genetic influences on aggression and punishment behavior complicates characterizations of humans as “altruistic” punishers and supports theories of cooperation that propose mixed strategies in the population. It also suggests important implications for the role of individual variance in genetic factors contributing to everyday behaviors and decisions.

The Feeling of Rationality: The Meaning of Neuroscientific Advances for Political Science

Recent advances in the neurosciences offer a wealth of new information about how the brain works, and how the body and mind interact. These findings offer important and surprising implications for work in political science. Specifically, emotion exerts an impact on political decisions in decisive and significant ways. While its importance in political science has frequently been either dismissed or ignored in favor of theories that privilege rational reasoning, emotion can provide an alternate basis for explaining and predicting political choice and action. In this article, I posit a view of decision making that rests on an integrated notion of emotional rationality.

On the Evolutionary Origin of Prospect Theory Preferences

Prospect theory scholars have identified important human decision-making biases, but they have been conspicuously silent on the question of the origin of these biases. Here we create a model that shows preferences consistent with prospect theory may have an origin in evolutionary psychology. Specifically, we derive a model from risk-sensitive optimal foraging theory to generate an explanation for the origin and function of context-dependent risk aversion and risk-seeking behavior. Although this model suggests that human cognitive architecture evolved to solve particular adaptive problems related to finding sufficient food resources to survive, we argue that this same architecture persists and is utilized in other survival-related decisions that are critical to understanding political outcomes. In particular, we identify important departures from standard results when we incorporate prospect theory into theories of spatial voting and legislator behavior, international bargaining and conflict, and economic development and reform.

Overconfidence in wargames: experimental evidence on expectations, aggression, gender and testosterone

Summary Overconfidence has long been noted by historians and political scientists as a major cause of war. However, the origins of such overconfidence, and sources of variation, remain poorly understood. Mounting empirical studies now show that mentally healthy people tend to exhibit psychological biases that encourage optimism, collectively known as ‘positive illusions’. Positive illusions are thought to have been adaptive in our evolutionary past because they served to cope with adversity, harden resolve, or bluff opponents. Today, however, positive illusions may contribute to costly conflicts and wars. Testosterone has been proposed as a proximate mediator of positive illusions, given its role in promoting dominance and challenge behaviour, particularly in men. To date, no studies have attempted to link overconfidence, decisions about war, gender, and testosterone. Here we report that, in experimental wargames: (i) people are overconfident about their expectations of success; (ii) those who are more overconfident are more likely to attack; (iii) overconfidence and attacks are more pronounced among males than females; and (iv) testosterone is related to expectations of success, but not within gender, so its influence on overconfidence cannot be distinguished from any other gender specific factor. Overall, these results constitute the first empirical support of recent theoretical work linking overconfidence and war.

The Heart of the Matter: The Security of Women and the Security of States

Does the security of women influence the security and behavior of states? Existing evidence linking the situation of women to state-level variables such as economic prosperity and growth, health, and corruption is fairly conclusive. Questions remain, however, concerning the degree to which state security and state security-related behavior is linked to the security of women. The women and peace thesis draws upon evolutionary biology/psychology for ultimate causes of this linkage, and sociological theories of social diffusion and psychological theories of social learning for more proximate causal mechanisms. Together, a new data resourcethe WomanStats Databaseand conventional methodology find a robust, positive relationship between the physical security of women and three measures of state security and peacefulness. In addition, a comparison of this proposition to alternative explanations involving level of democracy, level of economic development, and civilizational identity shows that the physical security of women is a better predictor of state security and peacefulness. Although these results are preliminary, it is still possible to conclude that the security of women must not be overlooked in the study of state security, especially given that the research questions to be raised and the policy initiatives to be considered in the promotion of security will differ markedly if the security of women is seriously considered as a significant influence on state security.

SHORT-TERM FORCES AND PARTISANSHIP

One of the most intriguing aspects of the debate regarding the persistence of party identification is that proponents of different schools of thought have each managed to use the same quasi-experimental data and similar state of the art techniques to defend their point of view. In this article we argue that this debate cannot be resolved with quasi-experimental data alone and propose another method that we believe can help us triangulate in on the correct answer: experimentation. Two experiments are performed and analyzed. The first tests the hypothesis that party identification is updated in response to the vote choice; the second tests the hypothesis that candidate evaluations influence party choices. The results of our experiments provide some additional support for the traditional conception of partisanship as the unmoved mover of American politics.

Testosterone and Aggression in a Simulated Crisis Game

This study investigated the impact of testosterone on aggression in a crisis simulation game. We found a significant positive relationship between levels of testosterone and aggression. Men were much more likely to engage in aggressive action than women. They were more likely to lose their fights as well. Since testosterone was around five times higher among men, and men engage in such fights more than women, there is an automatic statistical link between testosterone and aggression that is hard to separate from other possible gender-based causes.

The WomanStats Project Database: Advancing an Empirical Research Agenda

This article describes the WomanStats Project Database — a multidisciplinary creation of a central repository for cross-national data and information on women available for use by academics, policy-makers, journalists, and all others. WomanStats is freely accessible online, thus facilitating worldwide scholarship on issues with gendered aspects. WomanStats contains over 260 variables for 174 countries and their attendant subnational divisions (where such information is available) and currently contains over 68,000 individual data points. WomanStats provides nuanced data on the situation and status of women internationally and in so doing facilitates the current trend to disaggregate analyses. This article introduces the dataset, which is now publicly available, describes its creation, discusses its utility, and uses measures of association and mapping to draw attention to theoretically interesting patterns concerning the various dimensions of women’s inequality that are worthy of further exploration. Two of nine variables clusters are introduced — women’s physical security and son preference/sex ratio. The authors confirm the multidimensionality of women’s status and show that the impact of democracy and state wealth vary based on the type of violence against women. Overall, the authors find a high level of violence against women worldwide.