烟草配送体系建立的关键元分析

现代化的物流配送体系是提高卷烟销售网络建设水平的关键环节,是一项基础工程。为此,需要重点分析以下问题:一是将整个区域的电子地图及相关的专题图层存入空间数据库;二是对配送车辆进行GPS定位,及时掌握车辆的状况;三是降低运营成本,选择最短或最优的路径。这三个问题是整个新型烟草配送体系建立的关键之所在,本文对此进行了讨论。     

Integrated ecological-economic modelling of water pollution abatement management options in the Upper Ems River Basin

This paper presents the results of the FLUMAGIS project, in which we developed a spatial decision support system (SDSS) to support the implementation of the European Water Framework Directive (WFD). The modelling approach is based on the integration of ecological and socio-economic assessment methods, scale-specific and GIS-based data and knowledge modelling and visualization techniques. The project study area is the intensively cropped Upper Ems River Basin in north-western Germany. A method was developed that enables the transfer of scale-specific data and information. Analyses were performed for baseline conditions and specific management and planning scenarios to improve water quantity and quality at micro-, meso- and macro-scale. The results of the study indicate that substantial, expensive water and land management changes at different scales would be necessary to achieve the WFD water quality targets in this basin. Ecological-economic analysis of cost-effectiveness reveals that the costs of achieving certain goals of the WFD can vary more than tenfold depending on which measure is chosen out of the pool of management alternatives. Moreover, the study shows that the differentiation between landscapes and other regional characteristics although considered essential to the successful implementation of WFD measures is very data intensive.     

On the profitability of collusion in location games

In this note we take a first step towards the analysis of collusion in markets with spatial competition, focusing on the case of pure location choices. We find that collusion can only be profitable if a coalition contains more than half of all players. This result holds for location games played in k-dimensional Euclidean space as long as consumers are distributed via atomless density functions. For competition on the unit interval, unit circle, and unit square we also derive sufficient conditions for collusion to be profitable. The results have immediate implications for mergers in spatial markets.     

Exit and Upgrading in Response to Entry: The Case of Gasoline Retailing

Spatial competition models have established the importance of localized competition in determining competitive outcomes. However, few empirical studies attempt to determine to what extent actual local market conditions affect strategic decisions. This paper uses data provided by the acquisition of the Vancouver area Super‐Save chain of retail gasoline stations by ARCO to study the role of geographic space in competition, and the spatial response of the major competitors in the market to entry. The possibility of both accommodating and aggressive capacity responses by the major incumbent firms to entry are considered. While the empirical results show that proximity to ARCO increased the probability that a station shuts down, proximity to ARCO can explain only a limited amount of shutdown after ARCO’s entry. There is no evidence that incumbent firms used station locations and capacity changes to respond aggressively to ARCO’s entry with a spatial predation strategy.     

Two-step on-the-job search—Evidence from Taiwan

This study decomposes on-the-job search into two-step procedures. The first step is concerned with the dissatisfaction with the current job, and is very sensitive to the wage gap and other observed factors. The second step is concerned with initiating an on-the-job search, and is insensitive to the wage gap and most other observed factors. It is likely that the one-step approach overstates these observed factors, while it understates the unobserved factors that give rise to the subjective probability of finding a better job in the behavior of on-the-job search.     

Estimating regional trade agreement effects on FDI in an interdependent world

Recent research on trade and multinationals highlights that multinational firms’ integration strategies are complex and the degree of vertical integration varies in a multilateral world with many possible locations of activity. In particular, multinationals control a large fraction of trade within the block of developed countries. The most important regional trade agreements (RTAs) are signed between members of the very same block of economies. This gives rise to the question asked in the present paper: what is the impact of RTAs on FDI in an interdependent world? Recent spatial HAC estimation techniques are applied to both estimation and testing.     

Analysis of variance on indirectly measured variables

Abstract  When observations from a normal distribution can only be obtained indirectly by counting the number of subjects responding to a previously chosen dose, parameter estimates can be obtained by using probit analysis. Well-known is the maximum likelihood technique of parameter estimation, less known is the approach by weighted least squares. The latter approach is followed to compare the parameters of several normal distributions by testing their equality, in analogy with the analysis of variance. A practical situation gave rise to this study and it is worked out at the end of the paper.     

中国农业碳补偿率空间效应及影响因素研究--基于空间Durbin模型

探索农业碳补偿率空间关联情况、溢出效应及影响因素,可为分区制定农业减排措施提供理论依据。本文将农业生态系统的碳吸收、碳排放双重效应同时纳入考虑范围,在测算2007-2016年中国30个省(市、自治区)农业碳补偿率基础上,基于距离平方倒数权重矩阵,运用Moran’s I指数探究碳补偿率空间集聚情况,再构建空间Durbin模型对其空间溢出效应及影响因素展开探讨。结果显示:(1)农业碳补偿率表现出区域集聚态势,"高-高"集聚的省份均属于东北地区和西南地区,"低-低"集聚省份主要处于北部沿海地区、东部沿海地区和长江中游地区。随时间流逝,北部沿海地区的"低-低"集聚效应逐渐减弱,"高-高"集聚中心由东北地区转移至西南地区。(2)农业碳补偿率存在显著正向溢出效应,邻近省份农业碳补偿率提高1%,将导致本省农业碳补偿率增加0.439%,区域农业碳吸收能力呈互相促进、协同提升的演进特征。(3)农业经济发展、农林牧渔部门比例优化与造林力度均对本省农业碳补偿率具有正向影响,农林牧渔从业人数、化肥施用强度和草食牲畜占比则呈负向作用;源于溢出效应,邻近省份农业经济发展与部门比例优化均有利于本省农业碳补偿率的提高。建议各省份加强区域协作,调控关键影响因素,因地制宜探索多元化的协同减排增汇路径。     

Retail Price Fixity as a Facilitating Mechanism

Previous theoretical explanations for retail price fixity show that fixed retail prices can be consistent with either competitive or imperfectly competitive behavior. We develop a conceptual model of retail pricing wherein fixed price points are facilitating mechanisms for tacit collusion. A non-cooperative equilibrium in fixed retail prices is supported through credible threats to revert to Nash pricing if cheating is suspected. We test the implications of this model using a two-stage, ordered probit approach in weekly supermarket pricing data. The results show that price fixity does support collusive equilibria among retailers, but other factors may also explain retail price behavior.