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941.
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
942.
In general linear modeling, an alternative to the method of least squares (LS) is the least absolute deviations (LAD) procedure. Although LS is more widely used, the LAD approach yields better estimates in the presence of outliers. In this paper, we examine the performance of LAD estimators for the parameters of the first-order autoregressive model in the presence of outliers. A simulation study compared these estimates with those given by LS. The general conclusion is that LAD does not deal successfully with additive outliers. A simple procedure is proposed which allows exception reporting when outliers occur. 相似文献
943.
Reuven Karni 《决策科学》1985,16(3):284-298
Conventional production planning methods assume the existence of a medium- or longrange demand horizon. However, demand usually is known over a much shorter range; scheduling decisions must be made within this “decision window,” which rolls forward in time. This paper presents a new lower bound for lot-sizing heuristics in a rolling-horizon framework and compares it to the well-known Wagner-Whitin bound. The new bound indicates heuristic schedules that have costs close to the optimum. Rolling-horizon schedule costs are compared to corresponding static-horizon schedule costs (assuming the whole horizon is known in advance), using the ratio of decision-window size to the natural order cycle as a parameter. For values below unity, the rolling-horizon policy is significantly more costly. For values above one, the two policies have similar costs and actually converge as the parameter value increases. 相似文献
944.
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
945.
2007年6月1日开始实施的新《合伙企业法》是一部非常有效地法律,但其最大缺陷是仍然没有规定表见合伙制度。表见合伙与表见代理、与民事欺诈是有明显区别的,不能用表见代理与民事欺诈解决实践中的表见合伙纠纷。新《合伙企业法》第76条的规定让人困惑,像似表见合伙,实则不然。建立表见合伙制度更有利于保障交易公平和安全,彰显善意第三人的利益,充分救济善意第三人的权利。因此,我国应当建立表见合伙制度。 相似文献
946.
Families across the income spectrum experienced subjective feelings of economic strain during the Great Recession. Existing evidence suggests that much of that economic strain did not arise from individual‐specific economic shocks, such as unemployment or income loss, as much as it did from worry and uncertainty about the future. The authors tested a model in which a measure of subjective perceptions of economic strain was the key predictor of children's behavior problems and objective indicators of economic experiences were treated as control variables. To do so, they used new data from a population‐based sample of children ages 4–17 (N = 303) living in southeast Michigan during the period 2009–2012. They found that economic strain exhibited a qualitatively large independent association with internalizing behavior problems for White—but not Black—children. This association was statistically significant over and above objective indicators of economic experiences and the family psychosocial context. 相似文献
947.
John F.McLennan is well known for introducing the terms of “exogamy” and “en-dogamy” in Primitive Marriage:An Inquiry into the Origins of the Form of Capture in Marriage Ceremo-nies(1865) .In this book... 相似文献
948.
Dejian Lai Qiang Zhang Jose-Miguel Yamal Paula T. Einhorn Barry R. Davis 《统计学通讯:理论与方法》2017,46(18):8943-8951
Effective recruitment is a prerequisite for successful execution of a clinical trial. ALLHAT, a large hypertension treatment trial (N = 42,418), provided an opportunity to evaluate adaptive modeling of recruitment processes using conditional moving linear regression. Our statistical modeling of recruitment, comparing Brownian and fractional Brownian motion, indicates that fractional Brownian motion combined with moving linear regression is better than classic Brownian motion in terms of higher conditional probability of achieving a global recruitment goal in 4-week ahead projections. Further research is needed to evaluate how recruitment modeling can assist clinical trialists in planning and executing clinical trials. 相似文献
949.
侯凌霄 《吉林工程技术师范学院学报》2014,30(7):59-61
职业教育旨在培养“学历+能力”型的人才,而这种人才培养模式的实现主要依靠校企合作,传统的教学模式因此受到了挑战.本文在实证研究的基础上,结合需求分析和任务型教学法理论,对高职商务英语专业“校企合作”这一模式进行探讨,分析其在商务英语教学体系中的地位和意义,为商务英语教学,尤其是高职商务英语教学提供启示和参考. 相似文献
950.
Tyler M. Argüello 《Journal of gay & lesbian social services》2016,28(3):231-244
Queer theory often falls impotent in its palatability across disciplinary lines. I offer a conceptual article that interrogates the dis-ease and divide when considering queer theory in and for the health sciences. In so doing, I look to foster a process of making queer theory more tenable to applied practice—and to make practice in social work, at least, more queer. The exemplar of HIV is deconstructed as a preeminent discourse and health disparity. In the end, it is argued that queer theory may be an essential intervention in the arsenal of the helping professions. 相似文献