Can we rationally learn to coordinate?

In this paper we examine the issue whether individual rationality considerations are sufficient to guarantee that individuals will learn to coordinate. This question is central in any discussion of whether social phenomena (read: conventions) can be explained in terms of a purely individualistic approach. We argue that the positive answers to this general question that have been obtained in some recent work require assumptions which incorporate some convention. This conclusion may be seen as supporting the viewpoint of institutional individualism in contrast to psychological individualism.     

考虑质量失误的供应链博弈模型研究

在理性的制造商和供应商组成的二级供应链中,考虑存在产品质量失误的情况下,通过最优化方法选择中间品的质量水平和制造商的检测水平,以实现供应链的利润最大化.并结合实际情况,根据质量内部、外部失误的不同承担方式,讨论了三种质量损失承担方式,得到在整体损失由两者共同承担的情况下,通过制定合理的内、外部损失分配系数,可以使两者选择水平的纳什均衡解与供应链的全局最优解相符,从而实现供应链全局最优和局部最优的一致.所得结论对指导供应链的有效运作有着较好的实际意义和参考价值.     

两阶段供应链中三种定价方式研究

本文考虑渠道一体化对品牌建设的作用,在一个制造商和两个零售商的两阶段供应链系统中,其中确定性的市场需求与产品的市场零售价格有关,通过分析以下三种定价方式下的最优定价和库存策略下供应链成员和系统的收益,1)商品市场零售价格由零售商各自决定,两零售商和制造商之间存在着竞争活动;2)商品市场零售价格由制造商统一制定;3)市场零售价格、转让价格和系统库存水平按渠道协调的最优原则确定,确定了同一产品品牌内部的市场竞争、定价控制权及转让价格对渠道性能及品牌自身造成的影响,并由此提出了分散决策系统中的一种激励机制.     

基于集成供应的RS契约协调模型研究

在由供应商和制造商组成的两级供应链中引入集成商,研究了需求不确定且价格敏感条件下基于集成供应的3级供应链的协调问题,建立了满足渠道协调条件和集成供应条件的RS契约协调模型,给出了模型中RS契约参数的取值范围和取值过程,并用实例加以说明。利用模型不仅可以确定产品的生产量和销售价格,而且还可以通过RS契约参数实现供应链利润的分配。     

VMI对供应链性能的影响分析

建立了分散式供应链和VMI模式供应链的模型,比较了两种模式供应链的性能,研究表明在缺乏有效的协作机制的情况下,VMI的优势不能得到有效的发挥,提出了进一步提高VMI模式供应链性能的有效途径,最后给出了数值算例对结论进行了验证。     

销售商的努力影响需求变化的供应链的合约

本文首先重新考察报童模型,认识设计使供应链达到合作的合约的内在机制。在此基础上,提出一个设计供应链合约的一般模型,然后利用此模型分析在销售商的努力影响需求变化的情形下使供应链达到合作的合约的设计框架,同时提出一个在销售商的努力影响需求变化的情形下使供应链达到合作的合约。     

A delay-in-payment contract for Pareto improvement of a supply chain with stochastic demand

We consider a supply chain consisting of a single supplier and a single retailer with stochastic customer demand, which is operated over an infinite horizon. We propose a delay-in-payment contract to coordinate the supply chain. With this contract, the supplier allows the retailer to pay partial order cost at the ordering epoch, and to pay the remaining portion after a permissible number of periods. The system is formulated as a stochastic dynamic programming problem. It is shown that there exists a base-stock policy to be optimal. Compared with the traditional wholesale-price contract, the delay-in-payment contract with appropriate parameters can achieve a Pareto improvement (i.e., the performances of both the supplier and the retailer using the delay-in-payment contract are better than those using the wholesale-price contract). Numerical studies are performed to investigate both the effectiveness of the Pareto improvement, and the impact of the major parameters of the delay-in-payment contract on the system performance.     

广义ATO下基于多种团购模型的供应链协调

针对由多个供应商、单个制造商和零售商所组成的广义按订单装配式供应链，在上游多个供应商不确定的零部件（或商品）供应以及下游客户不确定的需求的环境下，首先分析基本模型中团购前后的零售商和制造商的利润变化，然后提出了团购的标准模型和协调模型，并比较三种不同的团购模型对各成员以及全局供应链绩效的影响。通过数学推导证明和仿真数据算例分析，结果表明：零售商自发的团购基本模型总是对制造商有利，而对零售商的好处是有限的；由制造商主导的团购标准模型在满足一定条件时是优于团购基本模型的，但有使得零售商甚至制造商自身受到损失的可能；而集中决策下的团购协调模型能够提升全局供应链的期望利润，实现渠道的帕累托改善，但协调的效果会受到团购客户组成结构的限制。     

Statistical considerations in clinical trial design with event-free survival as the primary efficacy endpoint

In late-phase confirmatory clinical trials in the oncology field, time-to-event (TTE) endpoints are commonly used as primary endpoints for establishing the efficacy of investigational therapies. Among these TTE endpoints, overall survival (OS) is always considered as the gold standard. However, OS data can take years to mature, and its use for measurement of efficacy can be confounded by the use of post-treatment rescue therapies or supportive care. Therefore, to accelerate the development process and better characterize the treatment effect of new investigational therapies, other TTE endpoints such as progression-free survival and event-free survival (EFS) are applied as primary efficacy endpoints in some confirmatory trials, either as a surrogate for OS or as a direct measure of clinical benefits. For evaluating novel treatments for acute myeloid leukemia, EFS has been gradually recognized as a direct measure of clinical benefits. However, the application of an EFS endpoint is still controversial mainly due to the debate surrounding definition of treatment failure (TF) events. In this article, we investigate the EFS endpoint with the most conservative definition for the timing of TF, which is Day 1 since randomization. Specifically, the corresponding non-proportional hazard pattern of the EFS endpoint is investigated with both analytical and numerical approaches.