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21.
Non-coding deoxyribonucleic acid (DNA) can typically be modelled by a sequence of Bernoulli random variables by coding one base, e.g. T, as 1 and other bases as 0. If a segment of a sequence is functionally important, the probability of a 1 will be different in this changed segment from that in the surrounding DNA. It is important to be able to see whether such a segment occurs in a particular DNA sequence and to pin-point it so that a molecular biologist can investigate its possible function. Here we discuss methods for testing the occurrence of such a changed segment and how to estimate the end points of it. Maximum-likelihood-based methods are not very tractable and so a nonparametric method based on the approach of Pettitt has been developed. The problem and its solution are illustrated by a specific DNA example.  相似文献   
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In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing.  相似文献   
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在层层比较中作者们认为西北贫困民族聚居区学校体育具有总体比较落后、地域特征明显;观念比较陈旧、经费严重不足;民族特色突出、发展潜力较大;少数民族青少年为主体,多数以一课两操为支撑四个方面的基本特征。  相似文献   
26.
Financial Issues Associated with Having a Child with Autism   总被引:2,自引:2,他引:0  
Data from the Family Experiences with Autism Survey are used to identify factors associated with financial problems in families that have a child with autism. Likelihood of financial problems was positively associated with use of medical interventions, having unreimbursed medical or therapy expenses, and having relatively lower income. Use of speech and language therapy was negatively associated with likelihood of financial problems. Many survey respondents forfeited future financial security and even experienced bankruptcy to provide needed therapy for a child with autism. Specific ways that financial advisors can help families that have a child with autism are outlined.
Dana Lee BakerEmail:
  相似文献   
27.
“三关爱”与建设计划生育文明   总被引:1,自引:0,他引:1  
长春市人口计生委率先提出的人性关爱、人情关爱和人文关爱,即“三关爱”理念,体现了一种自外而内、从下到上的追求,勾画出了计划生育文明的思路框架。人性关爱体现了权利本位的思想,尊重群众,理解群众。人情关爱体现了服务本位的思想。人文关爱体现了文化本位的思想。“三关爱”化解矛盾、创造和谐、促进发展。“三关爱”对政府的工作提出了全新要求,体现了管理型计划生育向服务型计划生育的历史转轨,重民权、合民情、贴民心,构成抓好人口计生工作、提升人口计生工作质量的新动力,是新时期人口计生工作值得关注的重要导向。  相似文献   
28.
信息系统工程监理在我国目前还是一个新生事物,无论是在理论研究上,还是在社会实践中,都还处于一个探索和起步阶段.要真正发挥ERP工程监理的作用,解决ERP成功率不高的问题,必须按照ERP工程的特点,建立相应的监理机制和实施模式.文章力图从ERP项目的特点和存在的问题出发,探讨ERP项目监理的有关问题.  相似文献   
29.
Portfolio evaluation is the evaluation of multiple projects with a common purpose. While logic models have been used in many ways to support evaluation, and data visualization has been used widely to present and communicate evaluation findings, adopting logic models for portfolio evaluation and using data visualization to share findings simultaneously is surprisingly limited in the literature. With the data from a sample portfolio of 209 projects which aims to improve the system of early care and education (ECE), this study illustrated how to use logic model and data visualization techniques to conduct a portfolio evaluation by answering two evaluation questions: “To what extent are the elements of a logic model (strategies, sub-strategies, activities, outcomes, and impacts) reflected in the sample portfolio?” and “Which dominant paths through the logic model were illuminated by the data visualization technique?” For the first question, the visualization technique illuminated several dominant strategies, sub-strategies, activities, and outcomes. For the second question, our visualization techniques made it convenient to identify critical paths through the logic model. Implications for both program evaluation and program planning were discussed.  相似文献   
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在介绍PERT网络模型基础上 ,从影响项目工期的风险因素出发 ,分析风险因素对项目活动的影响 ,提出了一种新的项目活动持续时间的估算方法 ,通过多次模拟确定项目持续时间分布和期望工期 ,并可找出影响项目工期最大的因素。  相似文献   
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