Work Attitudes,Work Conditions and Hours Constraints: An Explorative,Cross‐national Analysis

In this paper, individuals’ desire to work more or less than they actually do (hours constraints) is analysed in nine OECD countries using data from the 1989 International Social Survey Program (ISSP). Our results show that hours constraints deviate substantially from country to country. However, in all countries, the proportion of individuals wanting to work more (and earn more) than they actually do is larger than the fraction of workers wanting to work less (and earn less). Socio‐economic and demographic characteristics, work attitudes, and work conditions have a significant effect on hours constraints.     

供应链中具有产能限制的竞争企业中的信息共享研究

本文研究由一个供货商和两个制造商组成的二级供应链中,制造商之间的横向信息共享策略和供应商的定价问题。在模型中,上游供应商同时为下游两家制造商提供价格相同的原材料,下游制造商生产具有替代性的商品进行数量竞争,并受到相同的产能限制。以Cournot博弈为研究手段,求解了制造商的均衡订货决策和信息共享策略,分析比较了在不同的信息共享策略下制造商的利润、供应商的利润和批发价格。本文在研究制造商的信息共享策略时考虑了上游供应商的批发价格的影响。研究表明,当均衡解受到产能约束时,制造商的信息共享策略会反向。在某些情况下,完全信息共享和完全信息不共享都可能成为博弈的占优策略。上游供应商通过调整批发价格可以影响制造商的信息共享决策。该模型为上游供应商提供了一种最优定价策略,也为下游制造商提供了求解自身最优订货量和信息共享决策的方法。     

Increasing flexibility in shiftwork arrangements

Renewed interest in increasing flexibility in working time arrangements derives from both social and economic changes. The dominant reasons for greater flexibility in shiftwork arrangements relate to diverse business demands resulting from competitive pressures and rapid technological change, modern workers' personal preferences about the timing of work, and the reduction in hours of work. Many new patterns are applied to meet these demands. A review of innovative patterns reveals their close link with shorter working hours and diversifying career needs. Typical patterns include (a) hours averaging schemes, (b) flexible daily hours, (c) individualized free time schemes. (d) flexitime plus shift systems, (e) a combination of full-time and part-time systems, (f) job sharing, (g) temporary transfer to day work, and (h) career break schemes. Attention is drawn to multi-skilling of workers associated with more independent responsibility and closer communication. Changes to a flexible pattern are usually a result of consultations that respond to the conflicting interests of employers and workers. Support is necessary for a process of informed joint planning. Particularly useful are: (1) identification of operational demands and individual preferences about increasing flexibility in work schedules; (2) presentation of available options with information on implications for workers' health and social life; and (3) facilitating training and group consultation. The adjustments required depend greatly on how the tasks of individual workers are reorganized. In increasing the flexibility of shift schedules, it is important to learn from positive experiences of joint optimization of work content and working time arrangements.     

Increasing flexibility in shiftwork arrangements

Abstract

Renewed interest in increasing flexibility in working time arrangements derives from both social and economic changes. The dominant reasons for greater flexibility in shiftwork arrangements relate to diverse business demands resulting from competitive pressures and rapid technological change, modern workers' personal preferences about the timing of work, and the reduction in hours of work. Many new patterns are applied to meet these demands. A review of innovative patterns reveals their close link with shorter working hours and diversifying career needs. Typical patterns include (a) hours averaging schemes, (b) flexible daily hours, (c) individualized free time schemes. (d) flexitime plus shift systems, (e) a combination of full-time and part-time systems, (f) job sharing, (g) temporary transfer to day work, and (h) career break schemes. Attention is drawn to multi-skilling of workers associated with more independent responsibility and closer communication. Changes to a flexible pattern are usually a result of consultations that respond to the conflicting interests of employers and workers. Support is necessary for a process of informed joint planning. Particularly useful are: (1) identification of operational demands and individual preferences about increasing flexibility in work schedules; (2) presentation of available options with information on implications for workers' health and social life; and (3) facilitating training and group consultation. The adjustments required depend greatly on how the tasks of individual workers are reorganized. In increasing the flexibility of shift schedules, it is important to learn from positive experiences of joint optimization of work content and working time arrangements.     

不完全信息下再制造逆向供应链的定价与协调研究

本文探讨了回收量随机情况下的单一制造商和两个零售商组成的再制造逆向供应链系统的定价策略。在完全信息下,分别得到了Stackelberg博弈和联合博弈下的可行策略集合及可行解。在不完全信息下,运用信号甄别方法及激励相容约束得到了两个最优定价合同。研究表明:定价合同可以有效避免逆向选择问题,保证回收市场的稳定性;通过签订合同,制造商和零售商的利润均有所增加;制造商可通过零售商的履约表现控制其回收量,并对未完成任务的零售商进行惩罚;高运营成本零售商会不断降低运营成本以增加利润。     

基于知识量的知识作业评测研究

以知识量作为作业难度表征的重要指标;在讨论信息量、教学时间与知识量关系的基础上,根据BROOKES信息基本方程,建立了社会标准教学时间与知识量的映射关系;根据知识表达系统提出了基于社会标准教学时间的知识测度原理及其测度方法;结合岗位知识量的测度进行了算例说明.     

具有时间转换约束项目网络的时差分析

在传统的网络计划模型中,当所有的紧前工序结束后,当前工序就能够马上开始。但在实践过程中,由于许多工序会受到开始时间的约束,因此工序很少能在满足优先关系约束后的任意时刻开始,而具有时间转换约束的网络则能很好地描述此类问题。本文主要研究在时间转换约束下,不同类型的工序在网络中的时间特性变化情况,并在现有研究基础上,将网络中工序的时间参数由传统的算法转换成具有时间转换约束的时间参数,提出新的机动时间计算公式。最后以案例的形式分析比较传统网络与具有时间转换约束网络的区别,从而体现时间转换约束网络模型的实践价值。     

?konomie des Abschlusspr��ferwechsels

In this state-of-the-art article we survey the analytical and empirical work on the economic determinants and consequences of auditor changes. First, we define the term ??auditor change?? and touch on the legal constraints affecting auditor changes in Germany and in the USA. Additionally. we discuss the corresponding disclosure requirements associated with auditor changes in these countries. Auditor changes can be triggered by the client or by the auditor. We identify four categories under which auditor change incentives can be classified: (1) changes in contractual relationships of the client which in turn can cause a change in demand for audit quality; (2) changes of information possessed by the client or auditor concerning certain attributes of the audit; (3) changes in certain characteristics of the audit and (4) changes in regulation. We use this classification to structure our discussion of analytical models and empirical evidence. Turning to the consequences of auditor changes, we summarize the findings of the prior literature to show that capital market participants react on auditor changes and that they differentiate between both the initiator of auditor changes and the incentives to change auditor. We conclude with a discussion of some of the limitations of the current literature on auditor changes and identify some possible avenues for future research.     

Sharing shipment quantity information in the supply chain

This paper evaluates the benefit of a strategy of sharing shipment information, where one stage in a supply chain shares shipment quantity information with its immediate downstream customers—a practice also known as advanced shipping notice. Under a periodic review inventory policy, one supply-chain member places an order on its supplier every period. However, due to supplier's imperfect service, the supplier cannot always exactly satisfy what the customer orders on time. In particular, shipment quantities arriving at the customer, after a given lead-time, may be less (possibly more) than what the customer expects—we define this phenomenon as shipment quantity uncertainty. Where shipment quantity information is not shared with customers, the only way to respond is through safety stock. However, if the supplier shares such information, i.e. customers are informed every period of the shipment quantity dispatched, the customer may have enough time to adapt and resolve this uncertainty by adjusting its future order decisions. Our results indicate that in most circumstances this strategy, enabled by information technologies, helps supply-chain members resolve shipment quantity uncertainty well. This study provides an approach to quantify the value of shared shipment information and to help supply-chain members evaluate the cost-benefit trade-off during information system construction. Numerical examples are provided to indicate the impact of demand/shipment parameters on strategy implementation. While previous studies mainly focus on the information receiver's perspective, we evaluate a more general three-tier linear supply chain model via simulation, studying how this strategy affects the whole supply chain: the information sender, the information receiver and the subsequent downstream tier.     

Contract Negotiation and the Coase Conjecture: A Strategic Foundation for Renegotiation‐Proof Contracts

What does contract negotiation look like when some parties hold private information and negotiation frictions are negligible? This paper analyzes this question and provides a foundation for renegotiation‐proof contracts in this environment. The model extends the framework of the Coase conjecture to situations in which the quantity or quality of the good is endogenously determined and to more general environments in which preferences are nonseparable in the traded goods. As frictions become negligible, all equilibria converge to a unique outcome which is separating, efficient, and straightforward to characterize.     

评估供货量信息的共享在供应链管理中的价值

本文衡量了一种共享供货量信息的信息策略-即供应商向其客户(下游厂商)发布每次供货的具体数量,并通过数学建模以及模拟对此问题进行分析。结果显示,在大多数情况下,这种由信息技术支持的策略有助于供应链中的厂商适应并解决供货量不稳定的问题,供货量越是不稳定,企业越是能够从中获益。但是,当供应商及时稳定地补足缺货时,这种受益并不明显。本文的另一个发现是,供货量信息的共享可以使信息获得者受益,但是可能并不有利于发布者。也就是说,这样的信息共享能够为供应商的客户带来好处,但是供应商本身并不能因此获得显著的额外利益,反而要承担实施成本。这种不对称可能会阻碍企业间信息系统的实施,从而促使供应链成员协调信息沟通的费用,以激励供应商发布信息。我们的研究提供了对供货量信息价值进行量化的途径,同时也能够帮助供应链中的厂商评估他们在信息系统建设中的成本-收益率。     

基于激励相容契约的ATO式供应链交叉协调研究

考虑由两个零部件供应商与单个制造商组成的按订单装配式供应链中的信息不对称问题。以完全信息下各成员的利润作为基准,分析了成本类型信息占优的单个供应商"信息伪装"对纵向制造商和横向互补供应商所造成的损失,提出了基于激励相容的供应商-制造商纵向契约和横向互补供应商参与下的交叉协调契约。通过数学建模和仿真数据分析,研究表明：制造商主导的针对单个信息不对称供应商的激励契约,会产生"低端向下扭曲"现象,降低了横向供应商的最优订单量;制造商与横向的信息对称供应商分担信息租金而形成的交叉协调,在显示真实成本信息的同时,还可以提高最优订单量和整个供应链的全局利润。     

Is high touch finally here?

Can anyone single-handedly create a caring environment without adding hours to his or her work week? As turnover continues to rise, it's worth considering. Techniques managers say have worked for them are suggested, including: Monitor workloads; celebrate successes; make niceness an expectation; mentor; offer training as often as possible; stamp out problems before they go public; consider offering flexible hours and extended leaves for all; and introduce yeast to keep people stimulated. Will these strategies--all of which may not work for you--fatten your bonus this year? Probably not, unless top management is monitoring retention and doing occasional exit interviews. However, one of the byproducts is that employees don't stop with each other. They begin to treat patients better, something neither bribery nor threats may produce.     

The price-setting newsvendor with service and loss constraints

Current performance measurement systems consider not only financial measures, like costs and profits, but also non-financial indicators with respect to customer service, quality and flexibility. Using the newsvendor model, we analyse the respective influence of these possibly conflicting performance measures on important operations and marketing decisions, for instance the order quantity and the selling price of a product. As in the classical newsvendor model for price-independent as well as price-dependent demand distribution, the objective of the firm is to maximise expected profit. In this paper, we also consider a service constraint—a lower bound for the level of product availability—and a loss constraint—an upper bound for the probability of a loss occurring. For both models, we provide conditions for the existence of solutions. We then analyse the influence of demand variability using a set of conditions specifying the quantiles of the predetermined performance measures: a higher variability of demand implies a smaller admissible region of the decision variables. In the price-independent case, the optimal solution has a control-limit structure: the optimal order quantity is thus given either by the classical newsvendor solution or by the control-limits corresponding to the constraints. In the price-setting model with multiplicative demand, this structure is used to check whether small admissible prices are determined by the service constraint or by the loss constraint. Using these structural results, a procedure is developed to more easily enable the computation of the optimal values of the order quantity, selling price and expected profit.     

Tour Scheduling and Task Assignment of a Heterogeneous Work Force: A Heuristic Approach

The dual problem of work tour scheduling and task assignment involving workers who differ in their times of availability and task qualifications is examined in this paper. The problem is presented in the context of a fast food restaurant, but applies equally well to a diverse set of service operations. Developing a week-long labor schedule is a nontrivial problem, in terms of complexity and importance, which a manager spends as much as a full workday solving. The primary scheduling objective (the manager's concern) is the minimization of overstaffing in the face of significant hourly and daily fluctuations in minimum staffing requirements. The secondary objective (the workers’ concern) is the minimization of the sum of the squared differences between the number of work hours scheduled and the number targeted for each employee. Contributing to scheduling complexity are constraints on the structure of work tours, including minimum and maximum shift lengths and a maximum number of workdays. A goal programming formulation of a representative problem is shown to be too large, for all practical purposes, to be solved optimally. Existing heuristic procedures related to this research possess inherent limitations which render them inadequate for our purposes. Subsequently, we propose and demonstrate a computerized heuristic procedure capable of producing a labor schedule requiring at most minor refinement by a manager.     

Supplier selection with multiple criteria in volume discount environments

Supplier selection is a multi-criteria decision making problem which includes both qualitative and quantitative factors. In order to select the best suppliers it is necessary to make a trade-off between these tangible and intangible factors some of which may conflict. When business volume discounts exist, this problem becomes more complicated as, in these circumstances, buyer should decide about two problems: which suppliers are the best and how much should be purchased from each selected supplier. In this article an integrated approach of analytical hierarchy process improved by rough sets theory and multi-objective mixed integer programming is proposed to simultaneously determine the number of suppliers to employ and the order quantity allocated to these suppliers in the case of multiple sourcing, multiple products, with multiple criteria and with supplier's capacity constraints. In this context, suppliers offer price discounts on total business volume, not on the quantity or variety of products purchased from them. A solution methodology is presented to solve the multi-objective model, and the model is illustrated using two numerical examples.     

Multi-item EOQ inventory model with varying holding cost under two restrictions: A geometric programming approach

In this paper we provide a simple method to determine the inventory policy of multiple items having varying holding cost using a geometric programming approach. The varying holding cost is considered to be a continuous function of the order quantity. The EOQ inventory model with constant holding cost and the classical EOQ inventory model without constraints are derived.     

实报还是谎报——双边信息激励与供应链效率

探讨了双边不对称信息下供应链信息真实分享和谎报对效率的影响。首先,给出完全信息下的最优商品交易量和供应链利润作为比较基准。其次,构建双方信息真实分享的激励模型。研究发现激励双方信息真实共享所需的信息租金降低交易量和供应链利润。再次,构建允许信息谎报的交易量谈判模型。研究发现,供销双方都偏好高报自己的信息类型。个体谎报信息的幅度随着谈判力增加而减小。拥有绝对谈判力的一方不会谎报信息。供应链效率与谎报信息的幅度、成本上界以及销售价格相关。最后,通过数值算例对实报信息和谎报信息下交易量、供应链个体利润及效率进行对比分析。研究结果为管理实践提供一定的洞见:供应链企业是否激励双边信息分享可根据双方成本大小进行选择。     

不同决策目标下受资金约束零售商的最优采购策略研究

在提前订购和延时采购两种情景下,分别考虑最大化期望收益和最小化违约概率两种决策目标,对受资金约束零售商的最优采购量和相匹配的融资策略进行分析,结果表明,相比于以最大化期望收益为决策目标,以最小化违约概率为决策目标的零售商在提前订购中将奉行"保守"的采购量和融资策略（仅耗尽自有资金量采购而不融资）,而在延时采购中采取"激进"的采购量和融资策略（与最大化期望收益下一致）;在此基础上,对不同决策目标下受资金约束零售商的最优采购时机问题进行研究发现,在最大化期望收益下,零售商的最优采购时机由产品采购成本、市场容量均值、市场容量方差、自有资金量、银行贷款利率等多个参数共同决定,而在最小化违约概率下,零售商将始终选择延时采购。