Bayesian Inventory Management with Potential Change‐Points in Demand

We consider the inventory management problem of a firm reacting to potential change points in demand, which we define as known epochs at which the demand distribution may (or may not) abruptly change. Motivating examples include global news events (e.g., the 9/11 terrorist attacks), local events (e.g., the opening of a nearby attraction), or internal events (e.g., a product redesign). In the periods following such a potential change point in demand, a manager is torn between using a possibly obsolete demand model estimated from a long data history and using a model estimated from a short, recent history. We formulate a Bayesian inventory problem just after a potential change point. We pursue heuristic policies coupled with cost lower bounds, including a new lower bounding approach to non‐perishable Bayesian inventory problems that relaxes the dependence between physical demand and demand signals and that can be applied for a broad set of belief and demand distributions. Our numerical studies reveal small gaps between the costs implied by our heuristic solutions and our lower bounds. We also provide analytical and numerical sensitivity results suggesting that a manager worried about downside profit risk should err on the side of underestimating demand at a potential change point.     

Same Profession,Different People: Stratification,Structure, and Physicians' Employment Choices

Professions such as medicine are in the midst of profound change. This paper explores how recent stratifying forces within the medical profession relate to the trend toward salaried employment for physicians. Specifically, growing segments of female, black and Hispanic, and lower and middle class doctors are focused upon in the analysis. Several important structural forces related to managed care and the nature of medical work are discussed and examined as well. The results suggests that it is useful to consider factors internal to professions in explaining large-scale professional change. This does not mean forgetting about the role played by structure in this change. Instead, it supports incorporating stratification perspectives into studies of professionals and of considering micro levels of analysis which acknowledge and investigate the effects of intraprofessional diversity.     

Dynamic Pricing in the Presence of Myopic and Strategic Consumers: Theory and Experiment

We investigate retailers’ dynamic pricing decisions in a stylized two‐period setting with possible supply constraints and demand from both myopic and strategic consumers. We present an analytical model and then test its predictions in a behavioral experiment in which human subjects played the role of pricing managers. We find that the fraction of strategic consumers in the market systematically moderates the optimal pricing structure. When this fraction exceeds a certain threshold, the retailer offers relatively small late season markdowns to discourage strategic consumers from waiting and to incentivize them to buy during the early season; otherwise, the retailer offers relatively large markdowns to divert all strategic consumers to the late season, where the majority of revenue is made. Our model analyses suggest that the latter policy is optimal under fairly broad conditions. Our experiment shows that after some significant learning, aggregate behavior is able to approximate the key qualitative predictions from our model analysis, with one notable deviation: in the presence of a mixture of myopic and strategic consumers, subjects act somewhat myopically – they underprice and oversell in the main selling season, which significantly limits their ability to generate revenue in the markdown season.     

我国零售业的供应商管理库存实施策略研究

针对我国零售行业库存方面普遍存在的问题，零售业采取比较先进的供应商管理库存（VMI）管理模式，通过实施VMI降低企业的运营成本，提高企业的经营效益与效率。本土零售企业在借鉴外国的先进经验的基础上，结合实际情况来发展供应商管理库存，从而促进了我国零售企业快速发展，提高了市场竞争力。     

供应链库存合约研究

研究了制造商与其供应商的供应链最优库存策略和在非合作情况下的库存策略,比较分析了两种情况下的库存策略,并设计了库存合约;分析表明,制造商通过设计有效的转移支付合约,可以实现供应链库存的最优化。     

供应链库存协调策略研究

研究和分析了直运型供应链通过共同补给期协调库存的策略问题。在该供应链中,单一供应商提供单一产品给面临随机需求的单一零售商。在所提出的库存协调策略条件下,供应商指定共同补给期,当零售商按供应商指定的共同补给期作为其订货周期时,供应商提供零售商一定的价格折扣。这种协调策略可以视为Stackelberg博弈。在阐述了解决该博弈问题的方法后,进行了数值实验,分析了采用这种协调策略的利益。     

供应链中牛鞭效应问题研

牛鞭效应对企业的效益甚至整个国家的经济会造成严重的影响,多年来一直受到人们 的关注,但直到近年对它才有较为清晰的认识. 文章通过文献综述,讨论供应链中牛鞭效应的 现象和成因,减轻和消除该效应的对策以及进一步的研究方向     

一类供应链的Stackelberg主从对策问题研究

本文研究了供应链中的一般订货模式和协调模式,提出了一类供应链Stackelberg主从对策问题,卖方作为主方给出最小补充期策略,买方作为从方以最优库存策略响应。考虑一致价格折扣弥补买方的库存成本增加,以及买方的库存成本合理化,建立买方需求确定下的卖方成本优化模型。最后,应用遗传算法对石油分销系统Stackelberg主从对策问题离线仿真计算,得出Stackelberg主从对策均衡解。     

考虑产品变质的VMI混合补货发货策略及优化仿真

本文研究了“产品可变质”情况下的VMI库存补货与装运调度问题,并建立了Poisson需求过程下的VMI混合补货发货模型,根据此模型通过简单的规划求解即可得到使长期平均成本最小的最佳混合策略组合。由于模型推演过程中涉及到对补货周期内期望发货次数的近似估计,因而模型解是拟最优的。算例和模型仿真显示,模型结果与仿真结果十分相近,从而模型有效性得以确认。