Verti-zontal differentiation in export markets

Many trade models of monopolistic competition identify cost efficiency as the main determinant of firm performance in export markets. To date, the analysis of demand factors has received much less attention. We propose a new model where consumer preferences are asymmetric across varieties and heterogeneous across countries. The model generates new predictions and allows for an identification of horizontal differentiation (taste) clearly distinguished from vertical differentiation (quality). Data patterns observed in Belgian firm–product level exports by destination are congruent with the predictions and seem to warrant a richer modelling of consumer demand.     

功能主义视角下的社区分化与整合--以SY市C社区为例

改革开放以来,随着经济的不断发展和户籍制度的开放,中国城市化进程加快。同时,更多的人从农村迁移到城市,城市社区日益发展完善。在C社区,居民的社会地位、经济地位、文化地位、政治地位、社会评价标准处于严重的社会分化状态。而导致社区分化的最根本的原因就是强制性的拆迁征地,破坏了原来社区的共享价值观,让整个社区系统失去平衡。因此,建构一种健康、和谐、平衡的社区整合路径,具有重要的意义。     

基于产品差异化和规制条件下的斯坦克尔伯格模型研究

本文研究了产品差异化和规制条件下的斯坦克尔伯格模型,认为跟随企业的定价受主导企业定价的影响,但其定价受主导企业定价的影响的敏感程度随行业内跟随企业数量增加而下降.此外,本文还研究了在完全信息和不对称信息条件下政府对主导企业进行不对称规制时,为实现社会福利最大化对其征税的最优税率的确定.     

不对称R＆D活动下的市场绩效分析——基于有差异产品的寡头市场

为了研究在Stackelberg寡头竞争模型下企业在产品市场是否合作对市场绩效的影响,建立了寡头市场中面向R＆D工艺的两阶段博弈模型。采用逆向归纳法求出了产品市场合作与不合作两种情况下的古诺-均衡解。研究表明,从促进技术进步的角度来看,对于R＆D效率不太高的R＆D项目,产品市场合作策略优于产品市场竞争策略。从提高企业利润的角度来看,对于R＆D效率较高的R＆D项目,当产品差异不大时,产品市场合作策略优于产品市场竞争策略;当产品差异较大时,产品市场竞争策略优于产品市场合作策略。对于R＆D效率较低的R＆D项目,产品市场竞争策略优于产品市场合作策略。从提高消费者剩余以及改善社会福利的角度来看,对于R＆D效率较低的R＆D项目,产品市场竞争策略优于产品市场合作策略。     

新型农业经营主体的空间分异特征及其创新发展机制——以山东省为例

目的 新型农业经营主体的创新发展是我国实现农业农村现代化发展的重大战略,通过对山东省3类新型农业经营主体发展特征进行研究,有利于以点带面,提升各类新型农业经营主体发展质量。方法 文章以山东省1 585个新型农业经营主体为研究对象,综合运用空间分析方法和地理探测器模型系统揭示山东省3类新型农业经营主体空间分异特征及其创新发展机制。结果 （1）山东省3类经营主体呈集聚型分布,3类经营主体的空间离散程度均处在高非均衡水平,空间分布结构的区域差异明显。（2）3类经营主体呈现“多中心,连片化”的空间分布特征,家庭农场整体呈“带状”分布,农民专业合作社和龙头企业整体呈“环带状”分布。（3）家庭农场与农民专业合作社在县域层面呈显著的空间正相关性,龙头企业在市域层面呈显著的空间负相关性。（4）生产要素、政府能力、劳动力质量、技术创新、产业结构、金融服务、电子商务和市场化水平共同推动各类经营主体创新发展,且两两之间的交互能对3类经营主体创新发展具有协同增强的作用。结论 因此,针对不同类型新型农业经营主体创新发展特性,采取多元化、差异化的发展策略组合有助于推动各类经营主体的创新发展。     

Sushi or Fish Fingers? Seafood Diversity,Collapsing Fish Stocks,and Multispecies Fishery Management*

We present a model of a multispecies fishery, and we show the following. (i) Consumer preferences for seafood diversity can trigger a sequential collapse of fish stocks under open‐access fishery. (ii) The stronger the preferences are for diversity, the higher is the need for coordinated multispecies regulation. (iii) Second‐best optimal management of only one (or a few) species is less strict than socially optimal management of the same species. (iv) Myopic regulation of one species, ignoring spillovers to other species, can cause depletion of other stocks that would not be depleted under open access.     

全球化、柔性化、复合化、差异化:信息时代城市功能演变研究

结合信息技术对中国城市影响的实际,从信息技术影响下城市空间相互作用方式、空间结构的构成要素及其影响因素的变化出发,对信息时代国内城市功能特征进行研究变得尤为重要.全球化、柔性化、复合化、差异化已成为信息时代城市功能的主要特征;信息流和接入信息的能力变得尤为重要;每个城市都成为全球或区域城市网络的一个节点;部分服务的区位选择因此也表现出较大的弹性;城市居住空间分异仍然存在,影响因素越来越复杂.     

Product innovation and firms’ ownership

This paper explores (i) the incentives for an incumbent firm to acquire an entrant willing to sell a product innovation rather than openly competing with this entrant, and (ii) in case of acquisition, the incentives to sell simultaneously both the existing products and the new one rather than specializing on a single variant. We prove that, in some circumstances, an incumbent firm can find it profitable to make an acquisition proposal to the entrant. Nevertheless, in this acquisition scenario, a product proliferation strategy is never observed at equilibrium. Furthermore, while being available for sale, sometimes the innovation simply remains unexploited.     

Quality in competitive fresh produce supply chains with application to farmers' markets

Fresh produce supply chains have special characteristics, notably, that the quality of the product (fruit or vegetable) deteriorates continuously over time, even under ideal conditions. In this paper, we begin with explicit formulae for fresh produce quality deterioration based on chemistry and temperature and provide a path-based framework. We then focus on farmers' markets, the popularity of which has been growing due to consumers' greater awareness of and interest in product quality and emphasis on health. Farmers' markets, as examples of direct to consumer channels and shorter supply chains, are studied in the framework of game theory in both uncapacitated and capacitated versions. A case study of apples in Massachusetts, under various scenarios, including production disruptions, provides quantitative evidence of the applicability of our supply chain network approach.