Dual-credit courses expose high school students to college-level content and provide the opportunity to earn college credits, in part to smooth the transition to college. With the Tennessee Department of Education, we conduct the first randomized controlled trial of the effects of dual-credit math coursework on a range of high school and college outcomes. We find that the dual-credit advanced algebra course alters students’ subsequent high school math course-taking, reducing enrollment in remedial math and boosting enrollment in precalculus and Advanced Placement math courses. We fail to detect an effect of the dual-credit math course on overall rates of college enrollment. However, the course induces some students to choose four-year universities instead of two-year colleges, particularly for those in the middle of the math achievement distribution and those first exposed to the opportunity to take the course in eleventh rather than twelfth grade. We see limited evidence of improvements in early math performance during college. 相似文献
Journal of Youth and Adolescence - Previous studies suggest parents lack knowledge regarding child and adolescent lie-telling; however, no study to date has examined children’s and... 相似文献
An important component of crime scene reconstruction is bloodstain pattern analysis (BPA). Where BPA concerns impact patterns, estimating the area of origin is critical information for scene reconstruction. Traditionally, this is achieved by measuring individual bloodstains and performing trigonometric calculations; however, 3D scanning has been proposed as a viable alternative for overcoming logistical and practical concerns with the manual method. Therefore, this project aimed to establish whether the FARO Focus 3D scanner and FARO Zone 3D software can improve the accuracy of area of origin estimates relative to the manual method. We created a series of eight bloodstain impact patterns and performed paired analysis using the two methods to estimate areas of origin for each pattern. Our data suggested that FARO-derived estimates were generally more accurate than using the manual method. FARO-estimated heights of origin areas were generally closer to the true distance. Both methods underestimated the distance from the wall for most patterns originating 150mm or greater from the wall, but overestimated distances for patterns originating closer to the wall. The degree to which distances were underestimated increased significantly the further the blood source was from the wall and was greater for FARO-derived estimates. The results of this research contribute to the validation of these instruments for operational implementation for BPA and should be considered alongside the practical benefits of 3D scanning relative to manual methods. Further, 3D scanning can provide reliable BPA reconstruction documentation for technical review and court presentation. 相似文献
DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa. 相似文献
Political Behavior - As levels of residential economic segregation increase in the United States, politicians may have greater incentives to focus their attention on the demands of those living in... 相似文献
The Olsonian distinction between roving and stationary bandits outlines the rationale behind the transition from anarchy to the emergence of the predatory state. This two-bandit model may, however, be expanded to include more bandit types. In the case of Viking Age England, local English kings were unable to monopolize violence and defend their realms against competing Viking raiders. As the Vikings’ time horizon grew, so did the accumulated value of more formal taxation, and bandit types evolved in four steps. The first step is the Olsonian roving bandit, who executed Viking hit-and-run attacks and plunders during the second half of the tenth century. The second step is the gafol bandit; gafol is payment for leaving, paid to, among others, Swein Forkbeard. The third step is the heregeld bandit; heregeld is a tax to support an army for hire; most notably Thorkell the Tall’s. The fourth step is the Olsonian stationary bandit, i.e. the strongest military leader among the Vikings, Cnut the Great, settled down as the new king. Overall, the Olsonian two-bandit model can be expanded to a four-bandit staircase model, in which the new gafol and heregeld bandit types explain the steps from anarchy and short-run raiding to long-run formal taxation in a predatory state.
Policy Sciences - Persistent policy failures have been examined in recent years with a focus on the role of political systems. We evaluate the growth of dysfunctional policymaking in the U.S. and... 相似文献
Our study contributes to the search for the elusive catalytic effect of International Monetary Fund (IMF) lending on inflows of foreign direct investment (FDI). Recent scholarship has found that the catalytic effect is conditional on political regime and program stringency. We contribute to this literature by developing and testing a theory which describes how the catalytic effect also varies by economic sector. This is a departure from existing studies, which have tended to focus on aggregate FDI flows after crises. Our findings corroborate previous research, which finds that in general IMF lending has a substantial and negative effect on FDI. However, we find that the negative effect is concentrated in sectors that are highly dependent on external capital and have low sunk costs in the host country. Our findings are robust to several alternative explanations common in IMF literature, namely the importance of IMF program design and the ability of governments to make credible commitments to reform. Substantively, our findings suggest that investors are more likely to use IMF lending as an escape hatch in countries where FDI is dependent on external capital and has low sunk costs. 相似文献