Access prices,unbundling and product variety in European Internet markets

A fundamental policy in European broadband regulation is unbundled access to the local loop of the incumbent telephone company. We present comparative static results that show as the access price decreases, the retail price decreases, the variety of plans offered by Internet service providers increases and the quantity of each variety increases when a threshold condition is met. Using data from 18 European countries from 2006 to 2012, we find empirical support for these results when Internet product variety is measured by variation in download speeds.     

What drives cross-country differences in export variety? A bilateral panel approach

A worldwide event like the 2020 Coronavirus outbreak can only reinforce the interest in modelling trade diversification as a key factor in countries’ vulnerability to external shocks. This paper adopts a detailed relative framework to study the determinants of product-level export variety in a large bilateral panel of developing and developed economies (16,770 country pairs in the period 1988–2014). We find that country pairs characterized by large differentials in productivity and in the makeup of the labour force differ in export variety patterns. This result holds after controlling for other endowments and for trade costs. Further, productivity plays a significant role in the reduction of export variety dissimilarities between countries belonging to different income groups. Hence, without successful technological convergence the low-income economies will not be able to reduce their exposure to export risk.     

世界杀菌剂开发进展及趋势

综述了近年来世界杀菌剂新品种的开发进展，并介绍了杀菌剂工业发展的一些新特点。     

Product variety,sourcing complexity,and the bottleneck of coordination

Research summary: This paper studies the coordination burden for firms that pursue variety as their main product strategy. We propose that product variety magnifies the tension between scale economies in production and scope economies in distribution, giving rise to complex sourcing relationships. Sourcing complexity worsens performance and poses a dilemma for organization design: A hierarchical structure with intermediate coordinating units such as sourcing hubs reduces sourcing complexity for downstream distribution but creates bottlenecks at the hubs, hurting performance for both the hubs and downstream distribution. We empirically examine operations data for about 300 distribution centers within a major soft drink bottling company in 2010–2011. Results support our hypotheses, illuminating the source of complexity in multi‐product firms and the challenge for organization design in managing complexity. Managerial summary: This paper uses data for about 300 distribution centers within a major soft drink bottling company to study how a large product variety creates complex sourcing networks. We find that, in addition to poor performance (e.g., increased stockouts), complex sourcing networks can cause challenges for organization design. In particular, the benefits of converting an existing distribution center into a sourcing hub (i.e., reduction in sourcing complexity for downstream distribution) and the costs of doing so (i.e., reduction in performance for both the hubs and downstream distribution) are both real and significant. The design of an efficient sourcing network despite its complexity involves important managerial decisions. Experiences in building and managing such networks can be the basis of a dynamic capability. © 2016 The Authors. Strategic Management Journal published by John Wiley & Sons Ltd.     

The private value of plant variety protection and the impact of exemption rules

Plant Breeders Rights (PBRs) are sui generis IPRs intended to promote plant variety creation. Two characteristics distinguish PBRs from patents: the research and the farmers' exemptions. This article attempts to assess the impact of these exemption rules on the private value of PBRs. For this purpose, a microeconometric model of PBRs renewals is developed and estimated. This model extends previous models of patents renewals by allowing the use of PBRs-specific variables. It is argued that simple tests on the coefficients associated with key PBRs-specific variables can provide insights into the impact of the two exemption rules. Implementation to PBRs in France over the period 1973–2011 for six major crops suggests that neither the farmers' exemption nor the research exemption have a clear-cut effect on the private value of PBRs. We conclude that there is no evidence to argue in favor of a reform of PBRs.     

论成本变化规律的对偶性及其意义

文章基于总结规律以指导生产实践和课堂教学之目的,论述各种短期成本的四阶段变化规律及其内在联系,各种长期成本的四阶段变化规律及其内在联系,以及长短期诸多成本规律两两之间和群体内在联系之间的对偶性,并分析其对偶性差异及其产生原因。阐释各种长期成本曲线与各种短期成本曲线所处位置的对偶性及其原因,揭示了长期总成本曲线、长期平均成本曲线与生产扩展线之间的对偶性。     

Price competition in a differentiated products duopoly under network effects

We examine price competition under product-specific network effects, in a duopoly where the products are differentiated both horizontally and vertically. We emphasize the role of consumers’ expectations formation. When expectations are not influenced by prices, the market may be shared but shares must be equal unless product qualities differ or one firm, possibly even the low-quality one, may capture the entire market. When expectations are influenced by prices, which would be the case when there is commitment, competition becomes more intense and the high-quality firm tends to capture a larger market share. Under strong network effects there is a continuum of equilibria and the higher the prices, the smaller the difference between those prices can be. Requiring continuity of expectations, however, delivers a unique equilibrium where one firm captures the entire market.     

我国水果产品在东盟市场的竞争力研究

运用市场占有率、贸易竞争力指数、显性比较优势指数对我国与东盟主要水果出口国在东盟市场的竞争状况进行了测算和比较分析。研究结果表明:在总体上,我国水果在东盟市场上具有一定优势,但在多数水果品目上并不具有竞争优势;研究结论可为有针对性地增强我国水果在东盟的竞争力提供借鉴。