Testing hot-spots police patrols against no-treatment controls: Temporal and spatial deterrence effects in the London Underground experiment

Our understanding of causality and effect size in randomized field experiments is challenged by variations in levels of baseline treatment dosage in control groups across experiments testing similar treatments. The clearest design is to compare treated cases with no-treatment controls in a sample that lacks any prior treatment at baseline. We applied that strategy in a randomized test of hot-spots police patrols on the previously never-patrolled, track-level platforms of the London Underground (LU). In a pretest–posttest, control-group design, we randomly assigned 57 of the LU's 115 highest crime platforms to receive foot patrol by officers in 15-minute doses, 4 times per day, during 8-hour shifts on 4 days a week for 6 months. The effect of 23,272 police arrivals at the treatment hot spots over 26 weeks was to reduce public calls for service by 21 percent on treated platforms relative to controls, primarily when police were absent (97 percent of the measured effect). This effect was six times larger than the mean standardized effect size found in the leading systematic review. This finding provides a benchmark against the baseline counterfactual of no patrol in hot spots, with strong evidence of residual deterrence and no evidence of local displacement.     

Treatment format and external validity in international relations experiments

Political scientists use short vignettes or mock news stories to embed treatments in experimental survey designs. We investigate whether the choice of format entails a trade off between internal and external validity. On the one hand, short vignettes may improve internal validity by isolating key variables without overloading respondents with information, thereby mitigating satisficing and improving data quality. On the other hand, mock news stories may improve external validity by approximating the circumstances under which individuals consume political information, which may enhance the credibility of the information. We find no evidence, however, that short vignettes mitigate satisficing more than mock news stories. Nor do we find that mock news stories enhance individual perceptions of the credibility of the information. Instead, we find that short vignettes are susceptible to confounding, which mock news story mitigate. These findings have important implications for debates about the use of survey experiments in political science.     

Opting Out of Political Discussions

Methodological limitations have hindered our ability to understand the conditions that make individuals seek or avoid political discussions. We introduce a methodological approach to assess communication preferences in contexts where these choices are difficult to measure. We conduct three experiments to examine how the characteristics of the people in a discussion, as well as its topic, influence an individual’s “price” to participate. Participants indicated how much they would need to be compensated to participate in a short discussion about a randomly assigned topic (political or nonpolitical) under different group compositions (co-partisans, out-partisans, or a mixed group). We find that individuals demanded significantly more compensation to engage in a discussion with out-partisans than with co-partisans, for both political and non-political topics.     

What Kinds of Trade Liberalization Agreements Do People in Developing Countries Want?

One of the most striking developments in the global economy in the past decades is the rapid proliferation of preferential trade agreements (PTAs), with many of them concluded among or with participation of developing countries. On the presumption that current popular debates on trade policy are not so much about whether citizens want free trade but rather what kinds of trade liberalization they want, we examine individual trade policy preferences with regard to PTAs that can vary in content along several dimensions. To that end we carried out conjoint choice experiments embedded in representative surveys in three developing countries that differ strongly in income levels, political system, and trade liberalization history: Costa Rica, Nicaragua, and Vietnam. We conceptualize trade policy preferences as preferences over the scale and scope of trade liberalization, environmental and labor standards, and labor market access (migration). Two main findings emerge. First, non-economic considerations, such as sympathy/antipathy toward particular countries and environmental and labor rights concerns influence citizens’ preferences at least as much as factors based on standard economic logic. Second, preferences over particular facets (attributes) of trade liberalization, that is PTA content, are surprisingly consistent across countries, despite strong differences in macro-economic and political context.     

Policy design and domestic support for international bailouts

Financial bailouts for ailing Eurozone countries face deep and widespread opposition among voters in donor countries, casting major doubts over the political feasibility of further assistance efforts. What is the nature of the opposition and under what conditions can governments obtain broader political support for funding such large‐scale, international transfers? This question is addressed by distinguishing theoretically between ‘fundamental’ and ‘contingent’ attitudes. Whereas the former entail complete rejection or embrace of a policy, the latter depend on the specific features of the policy and could shift if those features are altered. Combining unique data from an original survey in Germany – the largest donor country – together with an experiment that varies salient policy dimensions, the analysis indicates that less than a quarter of the public exhibits fundamental opposition to the bailouts. Testing a set of theories on contingent attitudes, particular sensitivity is found to the burden‐sharing and cost dimensions of the bailouts. The results imply that the choice of specific features of a rescue package has important consequences for building domestic support for international assistance efforts.     

Let’s Intervene! But Only If They’re Like Us: The Effects of Group Dynamics and Emotion on the Willingness to Support Humanitarian Intervention

International relations (IR) studies on humanitarian intervention have debated both the nature and strength of intervention norms. This article contributes to this debate by exploring under what conditions individuals are willing to support military humanitarian intervention (MHI) and the psychological factors that influence whether, and the degree to which individuals support MHI. Taking a psychological approach, we hypothesized that individuals’ decision to support MHI is influenced by in-group favoritism and emotional responses to in-group suffering. We tested our theory with two experiments, each of which recruited roughly 200 American participants. Both experiments centered on the ongoing Syrian civil war and assessed Americans’ willingness to support intervention to protect different civilian groups. The results suggested that support for intervention was widespread, but not a majority view in most cases. The findings also suggested that participants exhibited slightly higher rates of support for intervention when those suffering were Christian, as opposed to Muslim. Furthermore, we found that the dynamics of support for intervention changed when chemical weapons were introduced into the scenario, which reframed the the crisis as a national security issue. Overall, our results suggest that individuals’ decisions to act upon norms can be influenced by the context of a crisis and individual level psychological factors, which have been under explored in IR scholarship on norms.     

Seeing the Lexus for the Olive Trees? Public Opinion,Economic Interdependence,and Interstate Conflict

Many scholars argue that economic interdependence and more extensive economic ties between countries decreases the risk of violent conflict between them. However, despite considerable research on the “capitalist peace” at the macro or dyadic level, there has been less attention to its possible individual-level microfoundations or underpinnings. We argue that public perceptions about economic ties with other states and the costs of conflict should influence the expected constraints on the use of force for leaders. Actual high interdependence and potential economic costs may not suffice to create political constraints on the use of force if people are unaware of the degree of interdependence or fail to understand the benefits of trade and the likely economic costs of disruptive conflict. We examine the linkages between individual perceptions about economic interdependence and their views on conflict and peace through a survey experiment, where we ask respondents in Japan about approval for belligerent actions in a territorial dispute with China and varying information about economic ties. Our findings indicate that greater knowledge and information about economic interdependence affects attitudes about territorial disputes and increases support for peaceful solutions with China.     

A role for structured observation in ethics

Progress in the natural sciences has depended upon the collection and use of carefully controlled observational data. By contrast, ethicists have failed to agree upon a role for observational data in their enterprise. Although factors embedded in the human condition obscure the role of observational data in ethical theory, barriers to the use of such data in ethics may be superable. Observation may not provide definitive answers to most ethical or metaethical questions. However observation of carefully constructed experimental conditions may provide the basis for cumulative progress in some branches of ethics.     

What Do Voters Want From Their Local MP?

This article summarises the findings from a study of what constituents want from their local Member of Parliament. 1 We make use of a survey technique known as conjoint analysis, wherein we present a national sample of British voters with profiles of hypothetical MPs who vary randomly in their characteristics, activities and behaviour. We find that voters like MPs who are independent from the party line and who do not focus exclusively on national policy work. MPs' gender and experience matter far less to constituents. Overall, voters want a Parliament made up of strong‐minded MPs who see their role as that of a constituency representative. This has important implications for parliamentary democracy in Britain.     

提高工具痕迹实验课效果的思考

教师要根据工具痕迹学实验课的目的,注重加强学生动手操作能力,注重实验课内容的创新,在传统工具痕迹实验方法的基础上,提高教学效果。