论俄美中亚博弈中俄罗斯形象的变迁

在重塑大国地位的思想指导下,面对美国在中亚的步步紧逼,俄罗斯以强化能源外交、加强军事合作、尊重中亚各国的选择和维护中亚各国现政权的稳定为手段,积极发挥自身优势,极大地扭转了在中亚地缘政治中的颓势,与中亚诸国的关系迅速回暖。双方在政治、经济和军事安全领域的合作逐步得到加强与深化,影响一体化进程的关键问题相继得以解决,相互关系出现了罕见的积极发展势头。     

The M4 Competition: Results,findings, conclusion and way forward

The M4 competition is the continuation of three previous competitions started more than 45 years ago whose purpose was to learn how to improve forecasting accuracy, and how such learning can be applied to advance the theory and practice of forecasting. The purpose of M4 was to replicate the results of the previous ones and extend them into three directions: First significantly increase the number of series, second include Machine Learning (ML) forecasting methods, and third evaluate both point forecasts and prediction intervals. The five major findings of the M4 Competitions are: 1. Out Of the 17 most accurate methods, 12 were “combinations” of mostly statistical approaches. 2. The biggest surprise was a “hybrid” approach that utilized both statistical and ML features. This method’s average sMAPE was close to 10% more accurate than the combination benchmark used to compare the submitted methods. 3. The second most accurate method was a combination of seven statistical methods and one ML one, with the weights for the averaging being calculated by a ML algorithm that was trained to minimize the forecasting. 4. The two most accurate methods also achieved an amazing success in specifying the 95% prediction intervals correctly. 5. The six pure ML methods performed poorly, with none of them being more accurate than the combination benchmark and only one being more accurate than Naïve2. This paper presents some initial results of M4, its major findings and a logical conclusion. Finally, it outlines what the authors consider to be the way forward for the field of forecasting.     

Induced Innovation in U.S. Agriculture: Time-series, Direct Econometric, and Nonparametric Tests

The hypothesis of induced innovation is tested for U.S. agriculture using a high-quality state-level panel data set and three disparate testing techniques—time series, direct econometric, and nonparametric. We find little support for the hypothesis. That conclusion is robust across testing techniques. However, as with all empirical tests of this hypothesis conducted to date, ours focus only on the demand side of the hypothesis. The hypothesis could have been rejected simply because the marginal cost of developing and implementing input-saving technologies for the relatively expensive inputs is greater than for the relatively cheap inputs.     

传感器系列课程教学改革实践与探索

在传感器系列课程的教学、实验、设计等教学环节中进行教学改革,将知识传授、能力培养、素质教育融为一体,提高了学生的学习兴趣,获得了较好的工程实训效果。     

农村环境治理不足的经济学分析及对策建议

农村环境主要是指农村居住环境和农业生产环境。目前,农村环境污染主要包括生活垃圾污染、种植业和养殖业产生的污染、乡镇企业造成的污染三种类型。农村环境治理不足主要是由于农村环境的公共产品特性及由其导致的市场失灵和政府缺陷。应通过建立环保组织机构、加大并充分利用政府的财政投入、改变二元化治理结构、积极开展广泛的公众监督等措施来加强农村环境治理。     

中国经济型饭店市场选择的空间特征及其影响因素——基于全国性与区域性连锁的对比分析

市场潜力和区位优势是连锁饭店选址的重要依据,两类连锁饭店市场选择具有差异性。回归分析结果表明:以GDP、人均GDP、非农业人口、消费品零售、批发零售总额为代表的市场潜力成为中国经济型连锁饭店总体市场选择中最重要的因素。另外,全国性经济连锁饭店在北京、上海这样的一线城市重点布局,选择铁路交通便利的城市,区域性经济连锁饭店在发源地城市的分店要显著多于其他城市,并开始逐步朝周边城市扩张。     

我国经济增长对二氧化碳排放影响的实证分析——基于一般均衡模型的分解方法

文章基于动态的一般均衡模型分析框架,利用中国1997--2040年的宏观经济数据和CO2排量数据,试图回答以下两个问题：第一,中国未来三十年的经济增长对CO2污染排量会有怎样的影响？第二,如何制定合理的政策实现中国政府承诺的CO2减排量？研究结论表明,如果实行正确的控污措施,在未来的30年里中国经济增长将不会造成CO2排量大量增加。通过对CO2排放量进行Divisia分解所得的结构效应和技术效应显示,污染排放量的有效控制可以通过重点减排活动、发展清洁燃料产品以及改进其使用技术得以实现。     

Evolving splines and seasonal unit roots in weekly agricultural prices

The univariate statistical properties of agricultural price series need to be examined as a first step in the analysis of price transmission mechanisms. However, in the case of weekly price series, increasingly available, the testing procedures usually applied in this step are not suitable to deal with evolving seasonal effects. In this study, a method of testing for seasonal unit roots in weekly series of agricultural prices is described. When the deterministic seasonal component does not remain constant over time, the restricted evolving spline model (RESM) is shown to be a useful parametric formulation to capture the deterministic seasonal pattern. Therefore, the RESM model should be included as a deterministic component in auxiliary regression for unit root tests at seasonal frequencies. This proposal is applied to three weekly series of Canary Islands banana prices. From the standard seasonal unit root tests, the null hypothesis is failed to be rejected at the 5% or 10% significance level at some seasonal frequencies for each one of the series. Once critical values are obtained by simulation exercises when the RESM model is included, the hypotheses of unit root are rejected at each one of the seasonal frequencies for all of the three series.     

Perspectives on Natural Resources in the Global Economy: Polity Series Review

Polity's ‘Resources’ series is a set of scholarly books, each of them dealing with a single resource or resource‐based commodity from a generally global or international perspective. As of this writing, nine books have been published in the series, six of which I review here. The series is a welcome contribution to interdisciplinary and overall critical perspectives on the social and environmental dimensions and implications of the international appropriation, production and exchange of natural resources. While there is no clear disciplinary bent or theoretical foundation running across the volumes, together the books develop a transnational perspective, stressing the linkages between specific sites of appropriation and production, on the one hand, and broader political economic networks of processing, finance, coordination, commercial distribution and social regulation, on the other. The books should serve as valuable references to researchers in academic, government and non‐government institutional settings, but should also prove valuable for undergraduate teaching on contemporary natural resource industries and their social regulation.     

理工科开设技术经济学课程的必要性及其教学方法

为了适应我国近年来市场经济飞速发展、人才的知识层次全面发展，理工科学生进入工作岗位后，技术经济的分析将必不可少，高校教育必须适应这种需求。文章论证了理工科开设技术经济课程的必要性，并根据个人的教学过程总结了教学经验。