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641.
This note examines the sensitivity of the basic economic-order-quantity inventory model to lot-size errors when holding costs are assumed to be a strictly increasing (though not necessarily linear) function of average inventory. In particular, we show that the penalty associated with ordering either too much or too little is a function not only of the size of the error but of the shape of the holding-cost curve as well. We demonstrate that, under certain conditions, even relatively small lot-size errors can be extremely costly. 相似文献
642.
643.
A model is presented that yields optimal production rates for a firm producing a contracted order. The model is unique in that it considers the influence of production rate and learning on total program cost. An application to the specific characteristics of two military production programs is presented. As demonstrated by the application, models of this type may be used as decision-making tools when negotiating the cost impact of contract modifications. 相似文献
644.
Scheduling university examinations is often done with the objective of spreading a student's required examinations over an examination week. That is the equivalent of the problem of minimizing the number of examinations a student must take on any one day. An approach to scheduling exams which relates the problem to the classical assignment problem is discussed. The model developed is a symmetry-constrained assignment model, and the solution method requires use of a branch-and-bound algorithm. Results from application of the algorithm to six semesters of actual data are presented. 相似文献
645.
In this paper we incorporate a linear demand function to model the price-volume causal relationship into stochastic cost-volume-profit (CVP) analysis. We assume that the objective function is to maximize expected profit; other objective functions are also discussed and compared. A linear stochastic model follows from which probabilistic statements can be easily obtained if the random variables are assumed to be multivariate normal. The basic framework is shown to be a special case of project value maximization where project value is the cash flow of the project discounted for time and risk according to the capital asset pricing model. Moreover, an intertemporal extension that considers inventory is developed. In summary, a new approach to stochastic CVP analysis that incorporates the management decision process in an uncertain environment is developed. 相似文献
646.
This paper examines the role of living arrangements in thequality of life of community-dwelling Chinese elders (aged 65 andover) currently residing in Vancouver and Victoria, BritishColumbia. Data are based on a random sample of 830 persons[response rate = 71.5%], who were interviewed in their homes inthe language of their choice in 1995–96. Three dimensions ofquality of life – satisfaction, well-being and social support –are examined for married men and women [living with spouse alonevs. living intergenerationally] and widowed women [living alonevs. living intergenerationally]. Few differences are found formarried persons, especially women; for widows, living alonesignificantly reduces quality of life in a number of areas.Regression analyses indicate that living arrangements are not asignificant predictor of life satisfaction or well-being formarried men and women. For widows, living arrangements determinewell-being but not life satisfaction.Overall, age, health status, and social support (havingfriends/confidante) are better predictors of quality of life forelderly Chinese Canadians than are living arrangements. Findingshighlight the importance of: empirically distinguishing maritalstatus and living arrangements in studying the quality of life ofelders; not homogenizing Chinese Canadian seniors with regard toliving arrangements; and focussing on Chinese elderly widows wholive alone as a group at risk of low well-being. 相似文献
647.
Studies on population history are often based on incomplete records of life histories. For instance, in studies using data obtained from family reconstitution, the date of death is right censored (by migration) and the censoring time is never observed. Several methods for the correction of mortality estimates are proposed in the literature, most of which first estimate the number of individuals at risk and then use standard techniques to estimate mortality. Other methods are based on statistical models. In this paper all methods are reviewed, and their merits are compared by applying them to simulated and to seventeenth-century data from the English parish of Reigate. An ad hoc method proposed by Ruggles performs reasonably well. Methods based on statistical models, provided they are sufficiently realistic, give comparable accuracy and allow the estimation of several other quantities of interest, such as the distribution of migration times. 相似文献
648.
For many older adults having access to affordable health care is a major concern. The present study's goal was to examine what factors were related to individuals' knowledge of late-life health insurance. A total of 131 women and 116 men (all aged 55-71) answered questions about private, Medicare, Medigap, and long-term care insurances. In addition, they answered demographic, personality, and health status questions. Results revealed that different factors are related to men's and women's knowledge of late-life health insurance options implying genderspecific educational interventions would be more effective than current educational interventions. 相似文献
649.
650.
Research suggests that victims of bullying may lack skills in emotional regulation, a process which facilitates coping with provocative situations to lessen the stress of negative emotions (Cicchetti, Ackerman, & Izard, 1995). The present study examined the emotional regulation and display patterns of victims during classroom bullying episodes. Children in grades one through six were observed during free play in the winter and spring of three consecutive school years. Results of the study indicated that the coping styles observed in victims of bullying can be grouped into two distinct clusters: 1) problem-solving strategies that are associated with the de-escalation and resolution of bullying episodes; and 2) aggressive strategies that tend to perpetuate and escalate the bullying interaction. Parallels were found between victims' and bullies' emotional displays. Results are discussed in the context of how maladaptive emotional regulation processes may act as risk factors for chronic victimization. 相似文献