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521.
Daniel G. Arce Sneha Bakshi Rachel T. A. Croson Catherine C. Eckel Enrique Fatas Malcolm Kass 《Public Choice》2011,149(3-4):465-478
We conduct experiments to test the collective action dilemmas associated with defensive and proactive counterterror strategies. Defensive policies are associated with creating public ??bads' (e.g., a commons) whereas proactive policies are akin to the voluntary provision of public goods. When combined, the inefficiency of collective action is exacerbated, resulting in a situation known as a Prisoner??s Dilemma squared (PD2). Deterministic versus probabilistic equivalent versions of the associated externalities are compared within a laboratory setting. Experimental results reveal that the collective action problem associated with counterterror strategies is deepened in uncertain environments, and is indeed a robust regularity that is not easily overcome; as individuals gain more experience, they become even more self-interested. 相似文献
522.
Wyman JF Dean DE Yinger R Simmons A Brobst D Bissell M Silveira F Kelly N Shott R Ohr J Howard R Lewis B 《Journal of forensic sciences》2011,56(3):694-699
Drug levels in decomposed individuals are difficult to interpret. Concentrations of 16 drugs were monitored in tissues (blood, brain, liver, kidney, muscle, and soil) from decomposing pigs for 1 week. Pigs were divided into groups (n = 5) with each group receiving four drugs. Drug cocktails were prepared from pharmaceutical formulations. Intracardiac pentobarbital sacrifice was 4 h after dosing, with tissue collection at 4, 24, 48, 96, and 168 h postdosing. Samples were frozen until assay. Detection and quantitation of drugs were through solid phase extraction followed by gas chromatograph/mass spectrometer analysis. Brain and kidneys were not available after 48 h; liver and muscle persisted for 1 week. Concentration of drugs increased during decomposition. During 1 week of decomposition, muscle showed average levels increasing but concentrations in liver were increased many fold, compared to muscle. Attempting to interpret drug levels in decomposed bodies may lead to incorrect conclusions about cause and manner of death. 相似文献
523.
Rachel Baker Elizabeth Friedmann Michal Kurlaender 《Journal of policy analysis and management》2023,42(2):488-524
The transfer between two-year and four-year colleges is a critical path to baccalaureate attainment. Yet students face a number of barriers in transfer pathways, including a lack of coherent coordination and articulation between their community colleges and four-year institutions, resulting in excess units and increased time to degree. In this paper we evaluate the impact of California's Student Transfer Achievement Reform Act, which aimed to create a more seamless pathway between the California Community Colleges and the California State University. We investigate whether the reform effort met its intended goal of improving baccalaureate receipt, and greater efficiency in earning these degrees, among community college transfer students. We tease out plausibly causal effects of the policy by leveraging the exogenous variation in the timing of the implementation of the reform in different campuses and fields of study. We find an overall positive effect on bachelor's degree attainment. This increase is driven entirely by increased transfer rather than an increased probability of earning a BA/BS conditional on transfer. We find only suggestive evidence that the policy led to greater efficiency (i.e., fewer units at graduation) in BA/BS receipt for transfer students. These findings are broadly consistent across student subgroups. 相似文献