Oil price shocks and volatility spillovers in the Nigerian sovereign bond market

This paper investigates volatility spillover in the Nigerian sovereign bond market arising from oil price shocks, using Vector Autoregressive Moving Average ‐ Asymmetric Generalized Autoregressive Conditional Heteroscedasticity (VARMA‐AGARCH) model. The paper covers the period March 22, 2011 to April 14, 2016 and makes use of the daily data of the Nigerian Sovereign Bond, Brent oil and West Texas Intermediate (WTI), respectively. We endogenously and sequentially detect structural break points using the test of Bai and Perron (2003) framework. In order to accurately estimate the model, we modify it by incorporating the break points into the VARMA‐AGARCH model, a process which if ignored would lead to model misspecification. The results obtained demonstrate a significant cross‐market volatility transmission between oil and sovereign bond market with ample sensitivity to structural breaks. The study also computes optimum weight portfolio and hedge ratio both with and without structural breaks and results equally indicate sensitivity to structural breaks.     

A NOTE ON PRICING OF PRODUCT QUALITY FOR STATUS CONCERNS

The paper analyses the optimal pricing of the product quality scheme when concerns for relative standing exist among consumers. We demonstrate that if the proportion of high‐value consumers is over (respectively, under) 1/2 of the total consumers, a firm has an incentive to select a large (respectively, small) quality gap among products. Therefore, there exists a cut‐off level for status concerns, which eliminates quality differences, and the firm assigns the same quality to all the consumers. These results indicate that consumers’ qualities will reflect distortions at the top and bottom. Accordingly, the firm's profit depends on which consumer category is larger.     

因材施教——声乐教学的重要法则

声乐与其它的艺术形式存在着明显的区别，由于难以形象地对声乐的乐理、思想等进行表达，因此在声乐教学的过程中如何有效地让学生更好地理解声乐知识，更好地掌握发声技巧等一直是广大声乐教师关注的重点。鉴于此，文章主要就声乐教学中的因材施教进行研究，通过努力在声乐教学中推动因材施教，学生才能对此会产生更浓厚的兴趣，更好地用声乐来表达内心的思想与情感。     

THE RELATIONSHIP BETWEEN EXPORT STATUS AND PRODUCTIVITY IN SERVICES: A FIRM‐LEVEL ANALYSIS FOR SPAIN

This paper analyses the relationship between export status and productivity in a major service exporter, Spain, during 2001–07. I find that exporters in the services sector are 45 percent more productive than non‐exporters. This productivity premium is larger for firms that supply non‐internet‐related services than for firms that supply internet‐related services. The results show that exporters were more productive than non‐exporters before beginning to export, and also that exporting increases productivity growth; however, this positive shock vanishes quickly.     

维吾尔族民众信任的权威格局分析——以四个地区个案为基础的实证研究

权威格局是各种权威要素因地位差异构成的功能互补的社会秩序协调机制，对权威格局的研究是从合法性角度对社会政治稳定必须具备的民众基础的考量。调查结果显示：新疆社会政治稳定具备牢固的维吾尔族民众基础。维吾尔族民众信任的权威格局中。以领导干部为代表的法理型权威在个人和社会事务两个领域普遍受到信任，占据权威格局的主导地位，辅之以在社会事务方面越来越受到信任的知识能力型人才代表的新型权威。经济愈发达的地区，情况愈是如此。宗教人士所代表的传统权威能够发挥的作用主要局限在社会事务领域中的道德规范，在经济欠发达地区的作用相对更大。     

资源环境约束下乌鲁木齐市低碳城市建设路径研究

城市是最大的温室气体排放主体和减排的主要承担者。本文以乌鲁木齐市低碳城市建设为研究对象,通过分析乌鲁木齐建设低碳城市的优劣势,提出低碳城市建设的路径,以期对乌鲁木齐市低碳城市的建设提供参考。     

Private Information in Life Insurance,Annuity, and Health Insurance Markets

Economic theory predicts that private information on risks in insurance markets leads to adverse selection. To counterbalance private information, insurers collect and use information on applicants to assess their risk and to calculate premiums in an underwriting process. Using data from the English Longitudinal Study of Ageing (ELSA), this paper documents that differences in the information used in underwriting across life insurance, annuity, and health insurance markets attenuate private information to different extents. The results are in line with – and might help to reconcile – the mixed empirical evidence on adverse selection across these markets.     

保乳手术治疗早期老年乳腺癌的临床价值

目的探讨保乳手术治疗早期老年乳腺癌的临床价值。方法将我院近期收治的早期老年乳腺癌患者150例,随机分为治疗组和对照组,各75例,治疗组患者进行保乳手术,对照组患者进行传统手术,对比分析两组患者经过手术后临床疗效,以及生活质量等。结果治疗组患者的手术中出血量、拔引流管时间、总的引流量及术后并发症显著优于对照组患者(P<0.05),同时治疗组患者经手术治疗后其生活质量高于对照组患者(P<0.05)。结论相比于传统的手术保乳手术具有手术后恢复时间短、并发症少及患者生活质量高等方面的优势,在临床治疗上可以进行大力推广。     

融入全球化的中国：世界生产贸易大逆转及其原因剖析

16世纪以后，以中国为代表的东方文明和西方文明出现分野，东方的科学技术越来越落后子西方，历史称之为“李约瑟之迷”，进入21世纪后，中国正在以前所未有的速度走出这个迷团。2011年，中国制造业产值为2．05万亿美元，而美国制造业为1．78万亿美元，首次超过美国成为全球第一，贸易也是如此，2012年中国货物进出口总额38670亿美元，美国为38628亿美元，也已经超过美国成为世界第一。分析这个大逆转的厚因，一是从体制上解放了了生产力，社会主义市场经济体制是人类社会主义伟大实践的创举；二是对外开放；三是坚定不移地贯彻了科学技术是第一生产力的伟大国策；四是融入了了全球的货币体系。     

论任务型教学法在高职中外合作办学大学英语教学中的运用

高等职业技术学院中外合作办学的学生入学分数低、基础差、学习动力不足,学习英语的态度、方法等都存在一些问题.任务型教学法强调学习者通过使用目的语进行交互活动,进而掌握语言交流的实际能力.“任务型教学”的运用和实践将对外语教学模式的转变、学生语言运用能力的培养以及学习者“互动式”学习方式的形成起到积极而有益的促进作用.