北京城区文化设施利用的空间分异研究——以博物馆、体育馆、展览馆为例

本文通过对北京市博物馆、体育馆和展览馆空间分布现状和问卷调查结果的分析,指出:北京市这三类文化设施的分布具有较为明显的南北、内外和城区间差异;同时,年龄、收入、家庭结构和受教育程度等是影响文化设施利用的非空间因素。在空间因素和非空间因素的共同作用下,文化设施利用表现出一定的空间分异特征和不平衡现象。在一定程度上导致不同地区居民在享受文化设施过程中的不平等性,以及较为明显的供求不匹配现象。在此分析基础上,对北京市文化设施建设提出了几点建议。     

基于用户偏好的垂直搜索算法

提出并研究、实现了基于用户偏好的垂直搜索算法(PVSA)。以领域特征为基本出发点,PVSA借助领域主题偏好向量、领域元数据权重因子、检索名词差异化、行业词典库更新等4项策略,有效地挖掘、表征用户的领域个性化偏好,以此为基础构建基于用户偏好的垂直搜索算法。实验结果表明了PVSA算法的有效性和可行性。     

新闻职业伦理四大争议问题评析

本文基于伦理和道德问题的分殊,重点探究当代新闻伦理四个基本问题。本文认为,在当今的全球化时代,许多社会基本问题充满了伦理争议,对于深刻影响社会的新闻传播职业来说,情况尤其是如此。如果说人们对于虚构造假、漠视生命等新闻职业道德问题通常可以明辨是非的话,那么新闻传播职业伦理问题则复杂得多,而且即便经过百家争鸣式的讨论,也难以求得一致意见。但是,我们通过这种以反思批判为特征的讨论,至少可以建立这样的共识:伦理思考和争论是一种极好的思维和表达训练,它对新闻从业者个人人格的完善、职业伦理以及公共伦理的养成和发展都是至关重要的。     

Limited Information and Advertising in the U.S. Personal Computer Industry

Traditional discrete‐choice models assume buyers are aware of all products for sale. In markets where products change rapidly, the full information assumption is untenable. I present a discrete‐choice model of limited consumer information, where advertising influences the set of products from which consumers choose to purchase. I apply the model to the U.S. personal computer market where top firms spend over $2 billion annually on advertising. I find estimated markups of 19% over production costs, where top firms advertise more than average and earn higher than average markups. High markups are explained to a large extent by informational asymmetries across consumers, where full information models predict markups of one‐fourth the magnitude. I find that estimated product demand curves are biased toward being too elastic under traditional models. I show how to use data on media exposure to improve estimated price elasticities in the absence of micro ad data.     

垂直专业化的决定因素与国际贸易——基于中国工业行业数据的经验研究

垂直专业化分工是跨国公司选择非股权形式国际生产快速发展的结果,应融合跨国公司理论与价值链理论来解释。利用投入产出表数据进行了实证研究,结果表明,中国工业行业FDI和自由贸易对垂直专业化具有较强的互补性,重要驱动力量是行业规模经济因素与知识产权保护水平的提高,且在不同行业中各种影响因素的作用表现有所差异。     

农业纵向一体化经营与农户横向一体化合作——我国“三农问题”及其出路解析

“三农”问题即“农村、农民、农业”问题.从农业的特殊性出发,认为通过实现农业纵向一体化经营、大力发展农户横向一体化合作经济组织是发展农业、保护农民利益、维护农村稳定、真正做到“农业增产、农民增收”的有效途径.     

‘Getting by’: life on the Copperbelt after the privatisation of the Zambia Consolidated Copper Mines

The privatisation of the Zambian Consolidated Copper Mines (ZCCM) in 1997 resulted in massive job losses, which marked the beginning of an unprecedented economic crisis on the Copperbelt. This coincided with the initiation of a house ownership policy by the Chiluba administration. Miners thus lost a job and gained a house as part of their retrenchment packages, which included some cash. The harsh material and psychological realities experienced by miners in this transition period spurred a wide array of informal economic activities in which the house and yard played important economic roles. It also tinged the experiences of former mine employees with nostalgia for a ‘golden’ past where the mining system provided a stable economic base and a wide range of social services. The disappearance of the old ZCCM system and its de facto control on socio‐economic differentiation sparked new processes of ‘class’ formation. This paper describes the livelihood processes and experiences of former mine employees, focussing on a high‐cost mine neighbourhood in the Copperbelt town of Luanshya.     

单一出厂定价制度下区位假设与厂商选址决策

本文修改Hotelling（1929）模型的基本假定,假定厂商边际生产成本为正,交通成本由消费者负担,厂商区位可以为内生变量,也可以为外生变量,在此假定前提下,分析厂商的最优的区位一价格策略,以探讨最大差异化原则或者最小差异化原则何时成立,或者不成立。     

风险规避型供应链的收益共享机制研究

探讨了由风险规避型零售商与风险规避型供应商组成的两级供应链协作激励问题.首先研究了Stackelberg主从对策模型下风险规避型零售商与风险规避型供应商的决策行为,并分析了双方的风险规避系数对双方决策行为的影响.然后,研究了垂直一体化模型下风险规避型供应链的决策行为,同样分析了双方风险规避系数对供应链决策行为的影响程度.最后,提出采用收益共享契约机制来协调该供应链.并通过数值实验进一步分析供应商与零售商的风险规避系数对双方的决策行为及收益共享系数的影响程度.     

Assortment Planning for Vertically Differentiated Products

We consider the problem of a retailer managing a category of vertically differentiated products. The retailer has to pay a fixed cost for each product included in the assortment and a variable cost per product sold. Quality levels, fixed, and variable costs are exogenously determined. Customers differ in their valuation of quality and choose the product (if any) that maximizes their utility. First, we consider a setting in which the selling prices are also fixed. We find that the optimal set of products to offer depends on the distribution of customer valuations and might include dominated products, that is, products which are less attractive than at least one other product, on every possible dimension. We develop an efficient algorithm to identify an optimal assortment. Second, we consider a setting in which the retailer also determines the selling prices. We show that in this case the optimal assortment does not include any dominated product and does not vary with the distribution of customer valuations when there is no fixed cost. We develop several efficient algorithms to identify an optimal assortment and optimally price the products. We also test the applicability of our methods with realistic data for two product categories.