Keep Your Friends Close? Supply Chain Design and Disruption Risk

In this article, we evaluate the relationship between supply chain design decisions and supply chain disruption risk. We explore two supply chain design strategies: (i) the dispersion of supply chain partners to reduce supply chain disruption risk versus (ii) the co‐location of supply chain partners to reduce supply chain disruption risk. In addition, we assess supply chain disruption risk from three perspectives: the inbound material flow from the supplier (supply side), the internal production processes (internal), and the outbound material flow to the customer (customer side) as a disruption can occur at any of these locations. We measure disruption risk in terms of stoppages in flows, reductions in flow, close calls (disruptions that were prevented at the last minute), disruption duration (time until normal operation flow was restored), and the spread of disruptions all the way through the supply chain. We use seemingly unrelated regression (SUR) to analyze our data, finding that lead times, especially supply side lead times, are significantly associated with higher levels of supply chain disruption risk. We find co‐location with suppliers appears to have beneficial effects to the reduction of disruption duration, and, overall supply side factors have a higher impact when it comes to supply chain disruption risk than comparable customer side factors.     

不同阶段研发投资对企业绩效的动态效应研究:基于中国上市公司的面板数据分析

研发投资是提高企业绩效的重要途径,不同阶段的的研发投资对于企业绩效的改善存在着差异化作用。本文构建了不同阶段研发投资对企业绩效影响效应的理论模型,并以我国103家上市公司2010-2016年的相关数据为样本,从动态效应的实证分析阶段和开发阶段两个阶段的投资强度对企业绩效影响的异同,结果发现:研究阶段和开发阶段的投资对企业绩效影响均具有正向的积极影响作用,开发阶段的投资在当期对企业绩效的影响较强但不可持续,研究阶段的投资具有滞后效应并且对企业绩效的提升有比较长远的影响。因此过多关注开发阶段的投资并不能有效提高企业绩效,企业应加大研究阶段的投资,以更好地实现其在提高企业绩效中的长效作用。     

Exploring Parameter Relations for Multi‐Stage Models in Stage‐Wise Constant and Time Dependent Hazard Rates

Single cohort stage‐frequency data are considered when assessing the stage reached by individuals through destructive sampling. For this type of data, when all hazard rates are assumed constant and equal, Laplace transform methods have been applied in the past to estimate the parameters in each stage‐duration distribution and the overall hazard rates. If hazard rates are not all equal, estimating stage‐duration parameters using Laplace transform methods becomes complex. In this paper, two new models are proposed to estimate stage‐dependent maturation parameters using Laplace transform methods where non‐trivial hazard rates apply. The first model encompasses hazard rates that are constant within each stage but vary between stages. The second model encompasses time‐dependent hazard rates within stages. Moreover, this paper introduces a method for estimating the hazard rate in each stage for the stage‐wise constant hazard rates model. This work presents methods that could be used in specific types of laboratory studies, but the main motivation is to explore the relationships between stage maturation parameters that, in future work, could be exploited in applying Bayesian approaches. The application of the methodology in each model is evaluated using simulated data in order to illustrate the structure of these models.     

关于“非遗”保护三个基本问题的话语分析

话语研究不仅关心人们如何言说,而且更为重视分析决定言说方式的深层动因。“非遗”保护既是一个社会各阶层权力角逐的场域,又是一个可通过不断协商达成共识的平台。人们对于“非遗”保护的认识人言言殊的根本原因在于参与“非遗”保护的社会各阶层各自的利益诉求并不完全一致。“非遗”保护工作正是在争论中逐渐确立了自身的工作目标、指导原则、实施方案,体现了极强的话语建构性。“非遗”作为一种传统生活方式的隐形载体,活态传承性是其精髓与灵魂;“非遗”保护必须以人为本,只有让“非遗”与现实的人民群众的日常生活发生联系和耦合,“非遗”保护才可能取得实效。     

In-Sample Inference and Forecasting in Misspecified Factor Models

This article considers in-sample prediction and out-of-sample forecasting in regressions with many exogenous predictors. We consider four dimension-reduction devices: principal components, ridge, Landweber Fridman, and partial least squares. We derive rates of convergence for two representative models: an ill-posed model and an approximate factor model. The theory is developed for a large cross-section and a large time-series. As all these methods depend on a tuning parameter to be selected, we also propose data-driven selection methods based on cross-validation and establish their optimality. Monte Carlo simulations and an empirical application to forecasting inflation and output growth in the U.S. show that data-reduction methods outperform conventional methods in several relevant settings, and might effectively guard against instabilities in predictors’ forecasting ability.     

Choosing summary statistics by least angle regression for approximate Bayesian computation

Bayesian statistical inference relies on the posterior distribution. Depending on the model, the posterior can be more or less difficult to derive. In recent years, there has been a lot of interest in complex settings where the likelihood is analytically intractable. In such situations, approximate Bayesian computation (ABC) provides an attractive way of carrying out Bayesian inference. For obtaining reliable posterior estimates however, it is important to keep the approximation errors small in ABC. The choice of an appropriate set of summary statistics plays a crucial role in this effort. Here, we report the development of a new algorithm that is based on least angle regression for choosing summary statistics. In two population genetic examples, the performance of the new algorithm is better than a previously proposed approach that uses partial least squares.     

1980年代“译介热”与中国审美话语的本体自律

20世纪80年代的“译介热”通过引进西方现代文论资源,实现了对政治意识形态“工具论”“反映论”的反拨与对抗,与此同构的是审美自律的进程和审美本体的建构.“审美自律论”和“方法多元论”成为“译介热”的两个主要支点,共同参与现代性人学启蒙,促使了现代派文学的文本发现与形式自律.“审美自律论”促使了审美活动从外部的“他律”转向了审美的“自律”,形式主义文论、结构主义文论等在译介热中引入中国,纷纷促使了美学和文学批评从外部转向内部、从内容转向形式、从思想内涵转向话语革命.同时也直接启发了中国现代派文学和先锋小说的创作,激活了新时期以来潜藏的“形式化”冲动,从而使得形式和语言实验在80年代中后期的文学创作中焕发出愈加重要的作用.     

口述史的复调价值及其实现

布罗代尔认为,理想的历史应该是多声部的。现代意义上的口述史的出现使基于文献书写的历史的单声部特征显露无遗。口述史不再是现代社会“沉默的大多数”发出的声音。以口头陈述为基础的口述史的叙事和以文献为基础的历史的书写都同样是有关历史事实的观念的反映。各具独立旋律的叙事与书写理应建立起和谐的关系而形成复调历史。这种复调历史并非杜赞奇基于话语分析方法,以解构民族国家单线叙事为目的的复线历史。口述史与历史二者之间互补互益的差异使反思性知识与批判性知识可以对过去的历史进行检讨并对历史事实进行更为深刻的理解。借鉴历史研究方法及滥觞于研究无文字民族的民族志方法是解决口述史实践中存在的诸多问题的重要路径。     

“经济人”:一种研究范式的革新与局限

公共选择理论的“经济人”研究范式主要包括经济人假设、交易政治学和方法论的个人主义三部分。通过对这种范式的私益内涵分析和利弊分析,指出其在革新传统政治学研究方法的同时也具有自身不可克服的局限。借鉴“经济人”研究范式对我国政治学乃至经济学研究都具有重要的方法论意义。     

论马克思理论的逻辑起点与出发点

马克思理论的逻辑起点是“本质的人”,出发点是“现实的人”。马克思理论的出发点和逻辑起点的区分,标志了马克思思维方式的彻底变革,为马克思理论的产生和形成奠定了科学的基础。同时,它对我们深化理解马克思理论和构建社会主义和谐社会来说有着极其重要的理论和实践意义。