我国中小企业三维差异化特征比较研究

作为推动国民经济增长和促进社会稳定的基础力量,中小企业在市场中扮演着最活跃的经济主体。与大企业相比,中小企业有其鲜明的成长特征,从动态演进视角选取体量规模、生命周期、要素需求三个维度,系统探讨了中小企业的差异化特征。结论显示:体量规模特征反映在个体与群体以及经济板块之间;生命周期特征体现在死亡陷阱和空间格局演变上;要素需求特征会根据阶段创新内容的不同做出适时调整。     

Construction of a service quality scale for the online food delivery industry

The main purpose of this study is based on qualitative and quantitative research procedures, and integrates the key service factors for the online food delivery (OFD) industry extracted by Internet Big Data Analytics (IBDA) to construct a OFD service quality scale (OFD-SERV). This study takes OFD customers in Taipei City as the objects. The results show that 20 key service factors for the OFD industry are extracted through IBDA. The OFD-SERV scale contains six dimensions including reliability, maintenance of meal quality and hygiene, assurance, security, system operation and traceability, a total of 28 items. The results from the structural equation modeling showed that the reliability, assurance and system operation have a positive impact on customer satisfaction. Finally, the findings provide knowledge and inspiration for the current OFD, and enable OFD operators and future researchers to more accurately identify the deficiency of service quality.     

川西北高原藏区农村贫困化分异机制探测

[目的]客观揭示农村贫困化地域分异机制,为科学推进川西北高原藏区精准扶贫创新途径、综合战略和认真贯彻落实中央治藏方略提供参考依据。[方法]应用地理探测器模型、GIS空间分析与地统计方法等方法,探测川西北高原藏区贫困村单位面积GDP分异的主导因素,揭示农村贫困化分异机制,提出不同贫困化地域类型的扶贫政策措施。[结果]影响川西北高原藏区农村贫困化分异的主导因素包括到主要交通道路距离、归一化植被指数(NDVI)、土地利用、年均温度和海拔高程等,各因素对贫困村经济发展分异的解释力分别为80. 76%、12. 82%、8. 82%、5. 45%和3. 96%;贫困村经济发展贫困化的分异机制存在明显差异,可归纳为交通区位约束型、自然环境约束型和经济区位约束型等三大类型;农村贫困化驱动机制下的贫困村精准扶贫政策措施亟需因地制宜、科学推进、讲求实效,有序推进精准扶贫战略。[结论]精准扶贫应分类指导、重点突破,尤其加强贫困村交通、水利、公共基础设施建设和特色农牧业产业培植,注重多种扶贫模式的综合集成。     

A reduced PDE method for European option pricing under multi-scale,multi-factor stochastic volatility

The number of tailor-made hybrid structured products has risen more prominently to fit each investor’s preferences and requirements as they become more diversified. The structured products entail synthetic derivatives such as combinations of bonds and/or stocks conditional on how they are backed up by underlying securities, stochastic volatility, stochastic interest rates or exchanges rates. The complexity of these multi-asset structures yields lots of difficulties of pricing the products. Because of the complexity, Monte-Carlo simulation is a possible choice to price them but it may not produce stable Greeks leading to a trouble in hedging against risks. In this light, it is desirable to use partial differential equations with relevant analytic and numerical techniques. Even if the partial differential equation method would generate stable security prices and Greeks for single asset options, however, it may result in the curse of dimensionality when pricing multi-asset derivatives. In this study, we make the best use of multi-scale nature of stochastic volatility to lift the curse of dimensionality for up to three asset cases. Also, we present a transformation formula by which the pricing group parameters required for the multi-asset options in illiquid market can be calculated from the underlying market parameters.     

结构性减税与扩张政府支出的宏观经济效应

为了深入研究不同类型财政政策对宏观经济的影响效应，本文构建纳入异质性家庭和细化财税工具的新凯恩斯DSGE模型，并着重模拟分析了不同类型财政政策冲击对居民消费、私人投资、通胀率以及总产出水平的动态影响效应。研究结果表明，不同类型财税工具对宏观经济的冲击效果存在显著差异，对于税收政策，劳动收入税减税能够有助于提升消费水平和消费需求，并调节和完善消费结构；而对于政府支出政策，转移支付规模的扩张通过刺激家庭消费，引导消费内需有效提升，从而带动经济增长方式由投资驱动型向消费驱动型转变，进而推动经济高质量发展。     

碳排放交易制度的节能减排路径：效率提升还是结构转型？——来自中国省级数据的准自然实验

以中国2013年以来实行的碳排放交易试点政策作为准自然实验事件，基于2000-2017年中国30个省市的面板数据，运用双重差分法实证检验碳排放交易制度的节能减排效应及影响机制。研究发现，碳排放交易制度有利于实现中国经济“节能”与“减排”的双重目标，并通过了一系列稳健性检验；作用机制检验表明，能源效率提升和能源结构转型都是碳排放交易制度实现节能减排目标的重要路径；能源效率提升在碳排放交易制度实现“节能”和“减排”中分别发挥了10.19%和5.93%的作用，而能源结构转型分别发挥了48.87%和52.95%的作用。这意味着中国碳排放交易制度实现节能减排的主要动力来自能源结构转型，而非能源效率提升。能源结构转型涉及问题更加宏观和深层，这为中国加快推进节能减排进程，特别是完成2030年碳达峰和2060年碳中和的国际承诺提供政策启示。     

集中连片特困地区扶贫产业发展的规模特征及其经济效率评价——以武陵山片区恩施自治州为例

[目的]在扶贫开发战略中成长起来的特色产业已经成为贫困地区经济发展和农民脱贫致富的支柱产业,特色产业的规模和经济效率直接决定着贫困地区脱贫致富能力。[方法]文章以茶叶、蔬菜代表武陵山片区湖北省恩施自治州扶贫产业,利用集中度指数、扩张弹性系数、单位面积的产值能力和产量能力以及单位产量的产值能力等指标进行扶贫产业发展的规模特征及其经济效率评价。[结果]“十一五”期间以来武陵山片区扶贫产业发展的产业地位逐渐提高、规模扩张优势显著、规模收益递增、投入规模扩张率高于产出规模扩张率、资源配置效率不断提高,比较经济效率差距持续扩大。[结论]扶贫产业亟待根据产业发展的生态化、集聚化和融合化等趋势,在规模扩张中强化特色产品的品质建设和效率优势品种生产专业化程度、提高生产技术水平以及完善产业化组织及其能力建设,提高扶贫产业的经济效率和致富能力。     

Comparison of dimension reduction methods for DEA under big data via Monte Carlo simulation

Data with large dimensions will bring various problems to the application of data envelopment analysis (DEA). In this study, we focus on a “big data” problem related to the considerably large dimensions of the input-output data. The four most widely used approaches to guide dimension reduction in DEA are compared via Monte Carlo simulation, including principal component analysis (PCA-DEA), which is based on the idea of aggregating input and output, efficiency contribution measurement (ECM), average efficiency measure (AEC), and regression-based detection (RB), which is based on the idea of variable selection. We compare the performance of these methods under different scenarios and a brand-new comparison benchmark for the simulation test. In addition, we discuss the effect of initial variable selection in RB for the first time. Based on the results, we offer guidelines that are more reliable on how to choose an appropriate method.     

寡头博弈模型中的时间记忆性质与预期对模型稳定性的影响

公平竞争是市场经济的灵魂,是发挥市场力量的关键.研究寡头垄断企业的竞争行为和竞争环境对中国强化反垄断,构建更加安全公平、有效竞争的经济市场意义重大.梳理寡头垄断企业中的价格竞争和产量竞争中的模型稳定性研究情况,通过模型的边界均衡点和局部均衡点来分析模型的稳定性,对寡头博弈模型中时间的记忆性与预期对模型稳定性的影响进行分析.