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Christopher Trenholm Barbara Devaney Kenneth Fortson Melissa Clark Lisa Quay Bridgespan Justin Wheeler 《Journal of policy analysis and management》2008,27(2):255-276
This paper examines the impacts of four abstinence-only education programs on adolescent sexual activity and risks of pregnancy and sexually transmitted diseases (STDs). Based on an experimental design, the impact analysis uses survey data collected in 2005 and early 2006 from more than 2,000 teens who had been randomly assigned to either a program group that was eligible to participate in one of the four programs or a control group that was not. The findings show no significant impact on teen sexual activity, no differences in rates of unprotected sex, and some impacts on knowledge of STDs and perceived effectiveness of condoms and birth control pills 相似文献
283.
This paper presents findings from a randomized field-training experiment designed to study the impact TASERs on police officers’
use-of-force decisions. Officers were randomly assigned to either a treatment group (with TASERs) or a control group (without
TASERs) and then participated in training scenarios involving different levels of suspect resistance. The study investigates
whether and to what extent officers armed with the TASER use it as an alternative to other types of less-lethal force (e.g.,
empty hands, pepper spray, and the baton) and the firearm, controlling for the level of suspect resistance. The findings indicate
that officers who were armed with the TASER were significantly less likely to deploy pepper spray and the baton in response
to aggressive physical resistance. Additionally, the results show that officers equipped with the TASER were less likely to
discharge their firearm when confronted with suspect resistance that was potentially lethal. No differences in police behavior
occurred in response to passive suspect resistance. 相似文献
284.
Sanders Shane Potter Joel Ehrlich Justin Perline Justin Boudreaux Christopher 《Public Choice》2021,189(1-2):257-277
Public Choice - Do informed electorates choose better candidates? While that question is straightforward, its answer often is elusive. Typically, candidate-quality information is neither salient... 相似文献
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The police murder of George Floyd sparked nationwide protests in the summer of 2020 and revived claims that public outcry over such high-profile police killings perpetuated a violent “war on cops.” Using data collected by the Gun Violence Archive (GVA) on firearm assaults of U.S. police officers, we use Bayesian structural time series (BSTS) modeling to empirically assess if and how patterns of firearm assault on police officers in the United States were influenced by the police murder of George Floyd. Our analysis finds that the murder of George Floyd was associated with a 3-week spike in firearm assaults on police, after which the trend in firearms assaults dropped to levels only slightly above that which were predicted by pre-Floyd data. We discuss potential explanations for these findings and consider their relevance to the contemporary discussion of a “war on cops,” violence, and officer safety. 相似文献
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Justin Michel M.D. M.Sc. Arnaud Paganelli M.D. M.Sc. Arthur Varoquaux M.D. M.Sc. Marie‐Dominique Piercecchi‐Marti M.D. Ph.D. Pascal Adalian Ph.D. Georges Leonetti M.D. Ph.D. Patrick Dessi M.D. M.Sc. 《Journal of forensic sciences》2015,60(2):269-273
Frontal sinuses (FSs) have been studied in radiology, anthropology, and forensic anthropology. This study aimed to determine whether it was possible to predict the age and sex of an individual using FS volume. Sixty‐nine anonymized CT scans were imported to MIMICS 10.01® software (Materialise N.V.), and each FS volume was calculated in mm3. There was an absence of significant difference between right and left FS volume (p = 0.173) and an absence of correlation between age and FS volume (Pearson's test; p = 0.705). Sexual dimorphism was significantly different (p = 0.001). However, the most discriminant datum for determining sex was found to be the total FS volume (sum of an individual's right and left FS volumes) with linear discriminant Fisher's function coefficients of ?2.759 for the male group and ?1.275 for the female group. With this model, 72.5% of our sample was correctly classified according to sex. 相似文献