Brand-specific tastes for quality

This paper develops a model of nonlinear pricing with competition. The novel element is that each consumer's willingness to pay for quality is private information and is allowed to differ across brands. The consumer's preferences are represented by a multidimensional type containing the marginal value of quality for different products. Buyers with high willingness to pay for quality also display strong preferences for particular brands, and require higher discounts in order to switch away from their favorite product. Therefore, competition is fiercer for buyers with lower tastes for quality, and hence more elastic demands. This is in sharp contrast to earlier models in which competition is fiercer for higher-taste, more valuable buyers. In equilibrium, firms either compete intensively for the entire market (providing strictly positive rents to all consumers) or shut down the least profitable segment of the market. Quality levels are distorted downwards for all buyers, except for those with the highest type. The number of competing firms and the degree of correlation across brand preferences enhance the efficiency of the allocation.     

大型研发企业的研发投入分析——基于全球前2000家企业研发投入数据

利用2006年全球研发投入居前2000位的企业数据,考察了这些企业研发投入的一些基本特征,如产业分布、国家分布,以及研发的集中度,并探讨了企业研发投入与企业规模之间的关系。研究结论是：研发具有产业异质性;研发在一些国家集中;企业研发的总量水平、研发比率、研发增长率与企业规模具有非线性关系．中型企业具有较高的研发投入量,而小型企业与大型企业具有较高有研发投入比,以及研发增长率。     

Scarcity, regulation and endogenous technical progress

This paper studies to which extent a firm using a scarce resource input and facing environmental regulation can still manage to have a sustainable growth of output and profits. The firm has a vintage capital technology with two complementary factors, capital and a resource input subject to quota, the latter being increasingly scarce through an exogenously rising price. The firm can scrap obsolete capital and invest in adoptive and/or innovative R&D resource-saving activities. Within this realistic framework, we first characterize long-term growth regimes driven by scarcity (induced-innovation) vs. long-term growth regimes driven by quota regulation (Porter-like innovation). More importantly, we study the interaction between scarcity and quota regulation. In particular, we show that there exists a threshold level for the growth rate of the resource price above which the Porter mechanism is killed while the scarcity-induced growth regime may emerge. Symmetrically, we also find that there must exist a threshold value for the environmental quota under which the growth regime induced by scarcity vanishes while the Porter-like growth regime may survive.     

A semiparametric panel model for unbalanced data with application to climate change in the United Kingdom

This paper is concerned with developing a semiparametric panel model to explain the trend in UK temperatures and other weather outcomes over the last century. We work with the monthly averaged maximum and minimum temperatures observed at the twenty six Meteorological Office stations. The data is an unbalanced panel. We allow the trend to evolve in a nonparametric way so that we obtain a fuller picture of the evolution of common temperature in the medium timescale. Profile likelihood estimators (PLE) are proposed and their statistical properties are studied. The proposed PLE has improved asymptotic property comparing the sequential two-step estimators. Finally, forecasting based on the proposed model is studied.     

Evaluation of similarity models for expected utility violations

A body of work proposes a decision cost argument to explain expected utility (EU) violations based on pair similarity. These similarity models suggest various measures over the risky pairs that define decision costs and benefits. This paper assesses the empirical modeling success of these similarity measures in explaining risky choice patterns showing EU independence violations. We also compare model fit for these similarity models relative to EU and to a selected generalized EU model. Although the candidate models exhibit some degree of substitutability, our results indicate support for models that use relatively simple measures as instruments for similarity.     

Robustness and inference in nonparametric partial frontier modeling

A major aim in recent nonparametric frontier modeling is to estimate a partial frontier well inside the sample of production units but near the optimal boundary. Two concepts of partial boundaries of the production set have been proposed: an expected maximum output frontier of order m=1,2,… and a conditional quantile-type frontier of order α∈]0,1]. In this paper, we answer the important question of how the two families are linked. For each m, we specify the order α for which both partial production frontiers can be compared. We show that even one perturbation in data is sufficient for breakdown of the nonparametric order-m frontiers, whereas the global robustness of the order-α frontiers attains a higher breakdown value. Nevertheless, once the α frontiers break down, they become less resistant to outliers than the order-m frontiers. Moreover, the m frontiers have the advantage to be statistically more efficient. Based on these findings, we suggest a methodology for identifying outlying data points. We establish some asymptotic results, contributing to important gaps in the literature. The theoretical findings are illustrated via simulations and real data.     

Escalation effects and the player draft in the AFL

This study investigates escalation effects in the Australian Football League (AFL). We use a sample of players selected in the AFL player draft (National Draft) between 1986 and 2002, and test for escalation effects by examining whether a player's draft order affects his subsequent utilisation by the club to which he was drafted. Utilisation is represented with measures of games played and tenure. Limited evidence of an escalation effect is found. Any relation between a player's draft order and his games played and tenure at the club to which he was drafted is concentrated in the early years of his career, and this apparent relation can be explained by the information about a player's ability that is contained in the player's draft order and by incentives for clubs to provide greater playing experience to higher ability players. Escalation effects in the AFL competition are therefore much weaker than have been found in studies of the US National Basketball Association (NBA). It is suggested that differences in the structure of the competitions may explain why the escalation effect in the AFL would be weaker than in the NBA.     

石家庄铁路入地三维地理信息系统的设计与实现

研究了世界首例国营干线铁路入地工程建设与运营管理问题,提出一种基于时间-事件-状态一体化时空数据模型,结合里程桩滑动条的施工信息动态查询方法,解决了隧道施工中连续型空间信息存储与管理的难点,构建了铁路入地三维地理信息系统,实现了三维建模、征地拆迁、地下管线管理、施工进度管理以及运营后的应急辅助决策支持等功能.     

LOD技术在三维地形图实时可视化中的应用研究

随着计算机科学、计算机图形学和现代测绘科学的迅速发展,三维数字地形图的研究与实现越来越成为人们研究和关注的热点,要实现三维地形图的实时可视化,应用LOD技术的研究又是非常必要的,如何针对大数据量三维地形图建立不同细节层次的模型和优化其算法又成为要研究关键技术。本文重点对LOD技术的原理、分类和应用进行比较与探讨。     

新型研发机构重在制度创新

新型研发机构是区域创新体系建设的催化剂。像中国科学院深圳先进技术研究院、清华大学深圳研究院和江苏产业研究院等机构在区域创新体制机制改革和服务地方经济等方面已成为一股不可忽视的新兴力量。但是,我国新型研发机构发展整体处于初期探索阶段,大部分新型研发机构在区域创新体系建设中存在“重数量轻质量”“重建设轻运营”和“重管理轻治理”的问题。其原因主要在于,我国在新型研发机构功能定位、新体制建立和管理机制等多方面改革的滞后。对此,我们需要进一步明确新型研发机构在区域创新体系中的功能定位,进一步向地方政府和研发机构赋权,进一步提高地方政府创新治理水平,进一步强化新型研发机构中的央地协同力度。