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The Effect of Breakfast in the Classroom on Obesity and Academic Performance: Evidence from New York City 下载免费PDF全文
Sean P. Corcoran Brian Elbel Amy Ellen Schwartz 《Journal of policy analysis and management》2016,35(3):509-532
Participation in the federally subsidized school breakfast program often falls well below its lunchtime counterpart. To increase take‐up, many districts have implemented Breakfast in the Classroom (BIC), offering breakfast directly to students at the start of the school day. Beyond increasing participation, advocates claim BIC improves academic performance, attendance, and engagement. Others caution BIC has deleterious effects on child weight. We use the implementation of BIC in New York City (NYC) to estimate its impact on meals program participation, body mass index (BMI), achievement, and attendance. While we find large effects on participation, our findings provide no evidence of hoped‐for gains in academic performance, or of feared increases in obesity. The policy case for BIC will depend upon reductions in hunger and food insecurity for disadvantaged children, or its longer‐term effects. 相似文献
274.
Substantial variation in national crime rates suggests social structure and cultural context influence offending and victimization. Several prominent criminological theories anticipate a positive association between the prevalence of cash in a society and its rates of pecuniary crime. We examined the association between one form of “cashlessness” and national robbery rates across nations (n = 67), controlling for several structural covariates of national crime rates. We obtained data on robbery from the United Nations Office on Drugs and Crime, and data on government-based cashlessness from the Global Financial Inclusion Database. We found nations with higher levels of government-based cashlessness had lower robbery rates (β = ?.41, p = .02). We also undertook several sensitivity analyses, including tests for a relationship with commercial cashlessness and for crimes like homicide and burglary. Our results suggest technological advancements that reduce cash in a society may have implications for a nation’s robbery rates. 相似文献
275.
Between 2004 and 2008 the Forensic Isotope Ratio Mass Spectrometry (FIRMS) network organised four Inter-Laboratory Camparison excercises with the aim of harmonising and validating isotopic measurements to be used for forensic applications.The samples distributed comprised materials of potential forensic interest such as packaging and pharmaceuticals to be analysed for δ2H, δ13C, δ15N and δ18O composition. As many as 30 international laboratories participated in these comparisons. Results have shown overall improvements for both within- and inter-laboratory reproducibility with respect to δ13C and δ15N measurements.Only a small number of laboratories returned results for δ2H and δ18O analysis and these results highlighted a need for improvement in the reproducibility of these measurements and a need to address the exchange of hydrogen between samples and ambient moisture. Results also highlighted the importance of sample preparation procedures and the need to standardise both these procedures and calibration against Standard Reference Materials. Future Inter-Laboratory Comparison exercises will assess the suitability of laboratories to submit data to national and international databases similar to those currently operated for fingerprints, DNA etc. 相似文献
276.
Sean Gillon 《The Journal of peasant studies》2016,43(1):117-139
Flexible allocation of crops among food and non-food uses is a key driver of global agri-food system change. Focusing on United States corn production, I explore the dynamics of flex crops, scrutinizing agri-industrial relationships and the distribution of agri-food system value and control. I situate crop flexing as exchanging use value, as opposed to converting use into exchange value without altering the commodity's use. Asking ‘Flexible for whom?' in the context of agri-food system crises, I find: (1) flex crops exacerbate contradictory food security and over supply crises, and that the distribution of flexibility and benefit in the agri-food system they provide depends on the organization of labor; (2) crises of accumulation tie flex crops to agri-food system financialization, which subordinates use to exchange value, obfuscating their relationship and distancing agricultural products and uses from their basis in nature and labor; and (3) debates over US corn flexing illustrate the utility of focusing on power and politics in crop flexing decisions and demonstrate US corn flexing to be a fix for climate and accumulation crises. Findings suggest that examining the distribution of value and control and the positions of labor and nature in the agri-food system may be productive for global flex crop research and advocacy in the future. 相似文献
277.
Olga Skarlato Sean Byrne Kawser Ahmed Peter Karari 《International Journal of Politics, Culture, and Society》2016,29(2):157-182
The International Fund for Ireland and the European Union (EU) Peace III Fund have provided external economic resources to local community projects in Northern Ireland and the Border region to support intercommunal relations, community development, economic development, peacebuilding and reconciliation. The British and Irish governments, the EU, and the USA see the economic aid as their commitment to support the peace process, nurture the local voluntary sector, and build the peace dividend. The research findings demonstrate that the reality on the ground is more complex. Some believe that the economic assistance has created employment opportunities, built capacity, and localized peacebuilding knowledge. Others are more sceptical and perceive that the aid has created dependency, facilitated a competitive milieu, and has not transformed relationships in a sectarian environment. 相似文献
278.
Types of coproduction and differential effects on organizational performance: Evidence from the New York City school system 下载免费PDF全文
Julio César Zambrano‐Gutiérrez Amanda Rutherford Sean Nicholson‐Crotty 《Public administration》2017,95(3):776-790
A growing body of literature explores the process of coproduction by citizens and government employees in providing goods and services, yet research that attempts to link coproduction to organizational performance offers contradictory findings. It is possible that these conflicting results are a consequence of trying to compare distinct categories of coproduction. This study identifies types of coproduction, classified by which organizational tasks citizens can influence during stages of policy design and implementation, and tests whether these types have different effects on student proficiency in Mathematics and English Language Arts using data from New York City schools between 2007 and 2009. This study then tests the degree to which different types of coproduction moderate the negative effect of environmental turbulence on performance. Results confirm that types of coproduction have varying effects on organizational performance and can reduce, and even eliminate, the negative effect of a turbulent environment on student outcomes. 相似文献
279.
Ted Joyce Dahlia K. Remler David A. Jaeger Onur Altindag Stephen D. O'Connell Sean Crockett 《Journal of policy analysis and management》2017,36(2):438-459
Randomized experiments provide unbiased estimates of treatment effects, but are costly and time consuming. We demonstrate how a randomized experiment can be leveraged to measure selection bias by conducting a subsequent observational study that is identical in every way except that subjects choose their treatment—a quasi‐doubly randomized preference trial (quasi‐DRPT). Researchers first strive to think of and measure all possible confounders and then determine how well these confounders as controls can reduce or eliminate selection bias. We use a quasi‐DRPT to study the effect of class time on student performance in an undergraduate introductory microeconomics course at a large public university, illustrating its required design elements: experimental and choice arms conducted in the same setting with identical interventions and measurements, and all confounders measured prospectively to treatment assignment or choice. Quasi‐DRPTs augment randomized experiments in real‐world settings where participants choose their treatments. 相似文献
280.
Traditionally, precontact Native Americans and Asian groups have been conflated for aspects of the biological profile due to their distantly shared genetic history, although this grouping remains largely unexplored. This study examines craniomorphic variability to ascertain whether Asian groups can be differentiated from each other and from Asian-derived groups using more fine-tuned models. Cranial and mandibular data for 35 nonmetric traits were recorded on precontact Native Americans (n = 150) and modern Japanese (n = 150) and Thai (n = 150) individuals. Chi-square analyses indicate that all groups exhibit statistically significant differences in most traits. Additionally, cross-validated binary logistic regression equations resulted in correct classification rates in the range of 65.0–93.3% and demonstrate that sex does not contribute to statistical models. Therefore, numerous traits provide discriminatory resolution that detects differences between the samples, thus highlighting the potential utility of nonmetric traits in identifying individuals beyond the traditional African, European, and Asian forensic ancestry groupings. 相似文献