基于SARIMA-SVR组合模型的 空气质量指数预测

空气质量指数(AQI)在波动中既具有整体的时间序列线性特征和明显的季节性波动周期,又具有多种因素影响的不确定性,为了提高AQI的预测精度,基于Ri386 3.3.3和Matlab R2014a两种编程软件,提出了一种同时具有线性和非线性的复合特征的时间序列预测模型——SARIMA-SVR组合模型。以太原市2014年1月—2019年7月的AQI月均值数据为基础,利用SARIMA时间序列模型进行线性预测,利用SVR模型对残差进行非线性预测,加和得到组合预测模型的预测结果,分析比较SARIMA,SVR和SARIMA-SVR这3种模型的预测结果和平均绝对百分比误差。结果表明,组合预测模型发挥了2种模型各自的优势,相较于单一预测模型的预测结果而言,其预测精度更高,稳定性更好。通过此模型得到的空气质量预测结果不仅可为人们的日常生活提供指导,而且可为大气污染的防治工作提供科学依据和借鉴意义。     

The Macro Pedagogy Debate: Teaching DSGE to Undergraduates Symposium

Dynamic stochastic general equilibrium (DSGE) models have become the workhorse of modern macroeconomics and the standard way to communicate ideas among applied macroeconomists. Undergraduate students, however, often remain unaware of their existence. The lack of specialized knowledge can hurt them if they decide to attend graduate school. Indeed, many first-year PhD students discover that the material they are currently learning differs significantly from what they mastered in college. But this can change. In this article, the author describes how to teach a full-fledged macroeconomics course where DSGE models take center stage. He discusses how to arrange such a course within a one-semester time frame, details the main components of instruction, and finishes with some thoughts based on his teaching experience at Macalester College.     

房产税促进地区产业结构优化的路径与异质性表现——产业转移和企业创新视角的沪渝比较

房地产市场过度繁荣带来的房价过快上涨会影响要素流动和企业行为，进而加剧资源错配，不利于地区产业结构优化。征收房产税可以有效抑制房价过快上涨，通过地区相对房价的下降减轻资源错配程度，并从影响产业转移和推动企业创新两条路径促进地区产业结构优化。运用合成控制法对上海和重庆房产税改革试点的政策效应进行评估，结果表明：重庆的房产税政策有效抑制了房价过快上涨，促进了先进产业的转入和创新水平的提高，进而显著提高了地区产业结构合理化和高级化水平，地区产业结构优化效应明显；上海的房产税政策对房价上涨的抑制作用不明显，高房价阻碍了高技能人才的流入，导致其产业高级化水平的提高更多依赖于低端服务业的发展，不利于地区产业结构合理化，总体上并未能有效促进地区产业结构优化。上海与重庆房产税政策效应的差异不仅源于其政策力度的不同，还由于两地经济发展水平和产业结构的不同。房产税政策必须有效抑制房价上涨，并应结合本地经济发展实际因地制宜，才能更好地促进地区产业结构优化。     

Interrelationship between crude oil and the stock markets of major demanders and suppliers in emerging and developed markets

This paper investigates the time-varying relationship between the stock markets of advanced and emerging oil-exporting and oil-importing countries and the international crude oil price indices. The results reveal that the time-varying among the oil-exporting and oil-importing countries responds similarly to aggregate supply- and demand-side effects. Oil-exporting countries have a slightly higher integration with the oil markets, while oil supply shocks have a slightly higher impact on emerging oil-exporting countries. The oil markets exhibit a lower time-varying relationship with the Asia-Pacific oil-importing markets, which indicates those markets may be attractive to investors during periods of turbulence in the oil market.     

中美贸易关系新形势下中国先进制造业升级路径研究

先进制造业是一国工业实力和竞争力的直接体现。目前,在中国先进制造业中,装备制造业竞争力明显提升、高技术制造业发展迅速、先进制造业出现集群式发展,但仍然存在创新能力较低、核心技术和零部件研发能力不强、先进制造业企业竞争力不强、缺乏有利的先进制造业发展环境等问题。应采取给予先进制造业发展更大的支持力度、坚持技术引进与自主创新融合、强化先进制造业的区域合作、引导企业提高自主创新能力等措施,推动中国先进制造业持续健康发展。     

餐饮企业的文化传承战略研究

随着社会不断地向前发展,餐饮企业文化总是处于运动变化之中。但这种变化是餐饮企业文化自身为适应其内外部的环境,而形成的一种“绝对运动”与“相对稳定”的活动过程。针对餐饮企业文化发展的这一规律,从继承优秀的传统文化、吸纳先进的外来文化两方面入手,探讨了餐饮企业文化的传承战略,从而使餐饮企业最终能够实现在继承中创新,在创新中发展的目的。     

先进材料领域关键技术预见的研究

坚持创新在我国现代化建设全局中的核心地位，把科技自立自强作为国家发展的战略支撑，需要通过开展技术预见科学判断和前瞻把握先进材料领域的“卡脖子”问题、关键核心技术和未来发展趋势，回答先进材料如何保障国家经济建设、国防安全和人民群众对美好生活向往的一些关键性问题。本研究旨在综合利用无监督机器学习方法、复杂网络理论以及链路预测算法，开展先进材料领域的热点和前沿识别和技术预见，探索性识别出先进材料9个子领域的56个技术方向课题。同时组织开展德尔菲调查，依靠专家智慧，综合考量未来愿景、经济发展、国防建设和民生需求，遴选出面向2035年的10项优先发展技术方向，为党和政府科学决策服务、为推动创新驱动转型和国防安全提供重要的战略支撑。     

Confirming the timing of phase-based costing in oncology studies: a case example in advanced melanoma

Aims: The utilization of healthcare services and costs among patients with cancer is often estimated by the phase of care: initial, interim, or terminal. Although their durations are often set arbitrarily, we sought to establish data-driven phases of care using joinpoint regression in an advanced melanoma population as a case example.

Methods: A retrospective claims database study was conducted to assess the costs of advanced melanoma from distant metastasis diagnosis to death during January 2010–September 2014. Joinpoint regression analysis was applied to identify the best-fitting points, where statistically significant changes in the trend of average monthly costs occurred. To identify the initial phase, average monthly costs were modeled from metastasis diagnosis to death; and were modeled backward from death to metastasis diagnosis for the terminal phase. Points of monthly cost trend inflection denoted ending and starting points. The months between represented the interim phase.

Results: A total of 1,671 patients with advanced melanoma who died met the eligibility criteria. Initial phase was identified as the 5-month period starting with diagnosis of metastasis, after which there was a sharp, significant decline in monthly cost trend (monthly percent change [MPC]?=?–13.0%; 95% CI?=?–16.9% to –8.8%). Terminal phase was defined as the 5-month period before death (MPC?=?–14.0%; 95% CI?=?–17.6% to –10.2%).

Limitations: The claims-based algorithm may under-estimate patients due to misclassifications, and may over-estimate terminal phase costs because hospital and emergency visits were used as a death proxy. Also, recently approved therapies were not included, which may under-estimate advanced melanoma costs.

Conclusions: In this advanced melanoma population, optimal duration of the initial and terminal phases of care was 5 months immediately after diagnosis of metastasis and before death, respectively. Joinpoint regression can be used to provide data-supported phase of cancer care durations, but should be combined with clinical judgement.     

国外先进地区区域创新发展的实践及启示

区域创新发展是当前引领经济发展的重要模式。区域创新发展的实践推动了区域创新理论研究的深入，并在更广大的范围内推动了区域发展实践。研究分析了美国硅谷、欧盟、日韩在区域创新发展方面的做法，并对促进区域创新发展提出建议。     

应用型本科大学数学课程考试模式研究

文章针对应用本科培养模式的特点,分析了大学数学课程教学及考试模式的不足,提出了应用型本科大学数学课程网络考试的改革设想。并且对应用型本科大学数学课程网络考试系统的架构和功能给出了框架式的设计,不但节约资源,而且可以较大程度上实现教考分离,将一考定结局的模式调整为分阶段分过程的考查。网络考试的模式不但可以更加真实合理地考核及评价学生,而且还能改变功利性教学的现状,客观地实现以考促学、以考促教的效果,更符合教育规律。从而印证了应用型本科大学数学课程网络考试模式改革的合理性。