Call Center Delay Announcement Using a Newsvendor‐Like Performance Criterion

The problem of estimating delays experienced by customers with different priorities, and the determination of the appropriate delay announcement to these customers, in a multi‐class call center with time varying parameters, abandonments, and retrials is considered. The system is approximately modeled as an M(t)/M/s(t) queue with priorities, thus ignoring some of the real features like abandonments and retrials. Two delay estimators are proposed and tested in a series of simulation experiments. Making use of actual state‐dependent waiting time data from this call center, the delay announcements from the estimated delay distributions that minimize a newsvendor‐like cost function are considered. The performance of these announcements is also compared to announcing the mean delay. We find that an Erlang distribution‐based estimator performs well for a range of different under‐announcement penalty to over‐announcement penalty ratios.     

The Roles of Bank and Trade Credits: Theoretical Analysis and Empirical Evidence

This study investigates the roles of bank and trade credits in a supply chain with a capital‐constrained retailer facing demand uncertainty. We evaluate the retailer's optimal order quantity and the creditors' optimal credit limits and interest rates in two scenarios. In the single‐credit scenario, we find the retailer prefers trade credit, if the trade credit market is more competitive than the bank credit market; otherwise, the retailer's preference of a specific credit type depends on the risk levels that the retailer would divert trade credit and bank credit to other risky investments. In the dual‐credit scenario, if the bank credit market is more competitive than the trade credit market, the retailer first borrows bank credit prior to trade credit, but then switches to borrowing trade credit prior to bank credit as the retailer's internal capital declines. In contrast, if the trade credit market is more competitive, the retailer borrows only trade credit. We further analytically prove that the two credits are complementary if the retailer's internal capital is substantially low but become substitutable as the internal capital grows, and then empirically validate this prediction based on a panel of 674 firms in China over the period 2001–2007.     

基于预算约束的多产品报童风险模型研究

对条件风险价值（conditional value-at-risk ,CVaR）准则下多产品报童模型进行研究。建立了以产品利润的CVaR值之和最大化为目标,具有预算约束的多产品报童模型。根据产品边际预算CVaR值的单调性,采用二分搜索算法对模型进行求解。应用算例分析零售商的预算与风险厌恶程度对最优订购策略的影响,得到结果:随着预算及风险厌恶程度的增加,零售商订购产品的种类增加;零售商的期望收益是风险厌恶程度的减函数。     

Durability,Transit Lags,and Optimality of Inventory Management Decisions

Two laboratory experiments on a single‐echelon inventory task show that inventory durability interacts with transit lags to create order volatility that exceeds demand volatility. Thus, inventory durability and transit lags cause managers to deviate from inventory decision optimality. Durability creates a large increase in order volatility because players adjust orders insufficiently to reflect current inventory and backlogs, much as they adjust orders insufficiently to reflect holding and backlog costs in newsvendor studies (e.g., Schweitzer and Cachon 2000). Transit lags exacerbate non‐optimal ordering by interfering with players' ability to correct prior errors. Our results suggest that non‐optimal inventory decisions can be driven by inventory and supply chain characteristics, even in the absence of the coordination and information sharing problems studied by Croson et al. (2005) and Sterman (1989a,b). We also examine the influence of features related to personality. We find little evidence that the interactive effects of durability and transit lags are altered by need for cognition, impulsiveness, or locus of control, suggesting that these features make supply chain management extremely difficult. These results imply that retailers and their upstream partners must consider the characteristics of their product and supply chains when interpreting demand signals received from downstream partners.     

The Newsvendor Model with Consumer Search Costs

We study the newsvendor problem when consumers are heterogeneous either in their valuations of the newsvendor's product, in their valuations of an outside option available to them, or in both valuations. In this context, we observe that the outside option, which represents the value that a given consumer associates with choosing not to purchase the newsvendor's product, may be interpreted as a search cost. Taking into consideration whether consumers' valuations differ on either one dimension of heterogeneity or on both dimensions, we develop a framework for classifying newsvendor models that incorporate demand‐management effects. In particular, we show that this framework includes both the newsvendor model with price‐dependent demand and the newsvendor model with endogenous demand as special cases. In addition to making a conceptual contribution by developing and drawing insights from this framework, we make technical contributions by providing more general sufficient conditions under which the underlying optimization problems are well behaved.     

基于顾客惰性行为的无理由退货策略研究

通过对加入了顾客惰性因素的无理由退货策略建立数学模型,发现当惰性顾客存在时,商家的最优销售价格为只考虑理性顾客时的标准价格与惰性损失之差;最优退货价格为产品的清货价格与边际惰性效用贡献率之和;与只考虑理性顾客的无理由退货策略相比,惰性在一定程度上会对销量产生负影响,但在相同环境下却能为商家带来更多的利润.     

报童订购行为: 订购成本与性别影响因素分析

本文采用数理模型和管理实验方法研究报童订购量拉向中心偏差问题．首先,分析企业订购水平行为,得出采用对偶平衡策略,即多订购所导致的成本等于少订购所导致的成本,可解释此偏差; 并且,在最差情况下,采用对偶平衡策略引发的成本不超过采用最优策略引发的成本的两倍． 其次,分析企业订购调整行为,得出: 第一,在高(低) 边际利润情境中,相对于前期少订购给企业带来的影响,前期多订购给企业带来的影响较小(大) ; 据此,企业可在高(低) 边际利润情境中助推决策者关注少(多) 订购造成的损失,以缓解拉向中心偏差． 第二,相对于女性被试,男性被试的当期订购量受前期订购量的影响较小,表明男性对自我的界定和决策行为相对不易受外界因素影响,此研究发现提醒企业需关注两性在订购决策行为方面的差异．     

Comparison as Incentive: Newsvendor Decisions in a Social Context

Explicit formal mechanisms dominate the discussion about incentives in Operations Management, yet many other mechanisms exist. Social comparison between peers may provide strong implicit incentives for individuals. Social comparison arises naturally in all social settings and may thus be unintended; however, many companies deliberately use it to motivate employees. In this study, we model a social context in which purchasers evaluate their performance relative to their peers; a feeling of inferiority results in a negative contribution to utility, whereas a feeling of superiority results in a positive contribution. We find that social comparison induces characteristic deviations from the newsvendor optimum ordering decision: if fear of inferiority outweighs anticipation of superiority, then purchasers herd together; the converse scenario incites actors to polarize away from each other. In both cases, actors will deviate from ordering the newsvendor optimum in order to satisfy social goals. Demand correlation and profit margins moderate the extent of the deviation.     

On the Preference to Avoid Ex Post Inventory Errors

The value of demand information underlies many supply chain strategies that aim at better matching supply and demand. This study reports on the results of a laboratory experiment designed to estimate the behavioral value of demand information. Relative to the commonly assumed benchmark of a rational risk‐neutral decision maker, we find that decision makers are consistently willing to pay too much for the option to eliminate the risk of supply not matching demand. Contrary to intuition, we show that risk aversion does not explain this result. We posit that demand information provides behavioral value because it mitigates regret from ex post inventory errors.     

带有马尔可夫竞争因子的多产品报童模型

在竞争的环境下考虑多产品报童问题。为了刻画多产品间的竞争关系，本文利用马尔可夫链构建多产品的需求转移模型，并根据模型的转移概率矩阵提出马氏竞争因子和综合竞争力等核心概念，进而结合卷积公式和雅可比行列式，将竞争因子的概念纳入经典报童模型的框架，构建了带有马氏竞争因子的多产品报童模型，同时在该模型的理论基础上给出了新的决策机制。模型的数据实验表明：竞争因子对多产品库存系统的最优订购策略具有重要的影响，关于产品的综合竞争力为单调递增函数；将竞争因子纳入多产品库存系统的决策机制，可进一步拓展报童模型在实际应用领域中的适应性以及提高库存系统的优化与控制的效用。