我国牧区草原生态补偿机制构建研究

［目的］通过构建一套科学、合理的牧区草原生态补偿机制，解决牧区近10年来主要实施的一系列生态治理项目和措施中存在的草原生态补偿标准普遍偏低、政策缺少灵活性、监管体系不够完善、缺乏相应保障机制等问题。［方法］通过对国内有关草原生态补偿机制相关文献分类梳理，基于我国牧区草原生态环境现状，对比分析国内外实践，总结国外成功经验，定性分析补偿机制要素，对草原生态补偿机制进行全面、系统地分析论述。［结果］我国牧区草原生态补偿主体应以各级政府为主； 补偿对象应包括牧区牧民、草原生态环境保护的投资者和建设者以及牧区地方政府； 因保护草原生态环境而导致牧区和牧民的发展权受限由此产生的机会成本作为草原生态补偿标准； 补偿方式以中央财政纵向转移支付为主，以市场补偿为辅的组合模式。保障机制需完善法律法规、公众参与、监督管理、绩效评估等方面建设。［结论］我国牧区草原生态补偿机制的构建须对补偿责任主体、补偿范围、补偿标准、补偿方式及补偿保障机制等各要素要进行整体性、系统性深入分析，才能确保草原生态补偿机制能够满足牧区实际需求，提供有力保障。     

Structural changes in heterogeneous panels with endogenous regressors

This paper extends Pesaran's (Econometrica, 2006, 74, 967–1012) common correlated effects (CCE) by allowing for endogenous regressors in large heterogeneous panels with unknown common structural changes in slopes and error factor structure. Since endogenous regressors and structural breaks are often encountered in empirical studies with large panels, this extension makes Pesaran's CCE approach empirically more appealing. In addition to allowing for slope heterogeneity and cross‐sectional dependence, we find that Pesaran's CCE approach is also valid when dealing with unobservable factors in the presence of endogenous regressors and structural changes in slopes and error factor loadings. This is supported by Monte Carlo experiments.     

全球价值链视角下中国的FTA贸易伙伴选择-基于贸易增加值数据的分析

在全球价值链视角下,FTA数量的增长和层次的提升对中国的对外贸易和经济增长产生了怎样的影响?中国下一步应该如何选择FTA对象?文章基于ADBMRIO和OECDICIO的国别(地区)贸易增加值数据,通过拓展的贸易引力模型研究了FTA数量和FTA层次对中国贸易增加值的影响.研究表明:FTA的建立使中国与成员国(地区)之间的贸易自由化和便利化水平进一步提升;目前FTA对贸易增加值的作用仍然以广延边际为主,FTA深度对贸易增加值的集约拉动需要继续加深;与传统贸易活动相比,FTA在全球价值链活动中起到的作用更加突出.效应异质性研究发现:从全球价值链的视角来看,与较发达国家和地区建立FTA对中国对外贸易的拉动作用最大;FTA参与度较高以及2008年金融危机之后与中国建立FTA的国家和地区对中国全球价值链参与度和竞争力的提升有显著的帮助;与中国距离较近的国家和地区建立FTA有利于中国贸易增加值的提升,但随着科技的进步,地理距离在对外贸易中的影响正在逐渐下降.因此,中国应加快FTA的全球战略布局,在增加FTA数量的同时,加强FTA的深度建设,注重FTA贸易伙伴的多元化,在亚洲邻国的基础上,加快与世界主要经济体之间的FTA谈判步伐.     

粮食与经济重心迁移路径及空间耦合关系分析*——以湖北省粮食主产县为例

[目的]我国的粮食安全问题一直备受关注,作为粮食安全重要保障的粮食主产区近年来却面临着粮食生产与经济发展协调性、可持续性下降的困扰。文章以湖北省46个粮食主产县为研究区,对其粮食生产与经济发展的耦合协调状况进行研究,以期为地方政府粮食安全政策制定提供参考。[方法]以研究区粮食产量、地区生产总值、行政区划图层为数据源,构建重心模型和空间耦合模型,对粮食主产县2006—2015年间粮食重心和经济重心迁移路径、粮食生产与经济发展耦合协调状况进行分析。[结果](1)研究期间粮食主产县的粮食重心和经济重心整体上皆向西北方向转移,经济重心始终位于粮食重心东南部,经济重心的移动幅度大于粮食重心,但经济重心的移动方向更稳定。研究区北部的粮食生产地位高于南部,南部的经济地位则高于北部,粮食生产的稳定性相对低于经济发展。(2)两重心整体上虽均向西北方向转移,但具体移动方向存在较大差异,两者空间重叠性整体下降,变动一致性减弱,空间耦合性变差。(3)粮食生产与经济发展空间一致性地域分异特征明显,相较于2006年,2015年粮食经济整体协调性进一步减弱,粮食生产与经济发展日趋分散。[结论]建立重心模型和空间耦合模型对粮食生产与经济发展耦合协调状况进行研究是有效可行的,为推动粮食生产与经济发展协调稳步发展决策提供一定的参考。     

Azéma martingales for Bessel and CIR processes and the pricing of Parisian zero‐coupon bonds

In this paper, we study the excursions of Bessel and Cox–Ingersoll–Ross (CIR) processes with dimensions . We obtain densities for the last passage times and meanders of the processes. Using these results, we prove a variation of the Azéma martingale for the Bessel and CIR processes based on excursion theory. Furthermore, we study their Parisian excursions, and generalize previous results on the Parisian stopping time of Brownian motion to that of the Bessel and CIR processes. We obtain explicit formulas and asymptotic results for the densities of the Parisian stopping times, and develop exact simulation algorithms to sample the Parisian stopping times of Bessel and CIR processes. We introduce a new type of bond, the zero‐coupon Parisian bond. The buyer of such a bond is betting against zero interest rates, while the seller is effectively hedging against a period where interest rates fluctuate around 0. Using our results, we propose two methods for pricing these bonds and provide numerical examples.     

农民工教育与职业的匹配及其工资效应——基于城市规模视角

农民工教育与职业的匹配状况对提高劳动力资源利用、增加劳动供给质量具有重要意义。本文使用中国流动人口动态监测调查2011~2016年微观数据,基于城市规模视角分析了农民工教育与职业的匹配状况对工资效应的差别。研究发现:人口规模越大的城市,农民工教育与职业的错配比例越高;中小城市农民工教育过度对工资的影响呈现工资嘉赏效应,大城市农民工教育过度对工资的影响以工资惩罚为主;而教育不足对农民工工资则普遍存在负向影响。农民工教育与职业不匹配对工资影响的理论机制表明,中小城市支持人力资本理论模型,而大城市和特大城市则支持分配理论模型。这意味着,农民工在中小城市表现出学历越高人力资本回报越高的特点;而在大城市,教育与职业适配则更为重要。因此,改善城市层面的教育-职业的适配性,让农民工在城市劳动力市场上自由流动和工作转换,进一步增强城市间劳动力资源的流动是相关政策调节的重点。     

A systematic review of pharmacoeconomic guidelines

Objective: To review, summarize, and analyze both similarities and differences of pharmacoeconomic (PE) guidelines, to enable researchers to access their characteristics and the current state of PE guidelines; furthermore, to learn which methodological issues still remain contested and to promote the methodological development of PE guidelines.

Materials and methods: The authors performed a search for PE guidelines using PubMed, the Cochrane library database, and the websites of the International Society for Pharmacoeconomics and Outcomes Research. Information of each guideline was extracted using a pre-designed extraction template, which included 22 aspects; the guidelines were summarized in the forms of charts, and their characteristics have been described.

Results: A total of 40 PE guidelines were studied. The most common methodological issues include the types of analysis, sources for effectiveness, use of quality-adjusted life-years (QALYs) to measure outcomes, and use of incremental cost effectiveness ratios to present results. The majority of the guidelines preferred a cost utility analysis with outcomes expressed in terms of QALYs. Most of the guidelines preferred meta-analysis or meta-analysis of the randomized controlled trials, and required a systematic review of all evidence. Issues that varied most in the guidelines were the choice of the comparator, recommended costs to be included, methods related to indirect cost calculations, methods of sensitivity analysis, and discounting rate.

Conclusion: A comparison of these guidelines revealed that a number of differences exist among them in several key aspects, and some critical methodological issues still exist, for which no best solution is available. Furthermore, efforts need to be made to develop harmonious methods for the PE, and to improve the transferability of the outcomes of PE evaluations.