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61.
In the paper we present a new method of calculating sampling intervals, so-called windows, allowing an experimenter some flexibility in timing the sample collection, while a minimum required design efficiency for parameter estimation is assured. The method is based on the Equivalence Theorem for D-optimality what makes the length of each window related to the parameter sensitivities. An example of calculating the windows in a pharmacokinetic study is presented. Some other methods of calculating efficient sampling windows are briefly discussed.  相似文献   
62.
Awkward Customers? Parents and Provision for Special Educational Needs   总被引:1,自引:1,他引:0  
This article selectively reports on a small-scale qualitative exploration of the experiences of families who had undergone recent conflict with special educational needs (SEN) professionals. The data were collected over the spring and summer terms of 2001 from 10 families in two local education authorities (LEAs) in the English midlands. The research aimed to examine the parents' perspectives on points of conflict or dissatisfaction between themselves and education professionals. It was concerned with the parents' points of view regarding their pursuit of desired outcomes for their children and the factors that helped or hindered their endeavours. The project found that the parents' negotiation of the SEN system was held by them to be exceptionally difficult and stressful compared to other troubling issues in their lives. The research suggests that dissatisfactions with SEN provision have important implications for the management of LEA Parent partnership Schemes (PPS) in ameliorating the differences between parental aspirations and governmental ambition.  相似文献   
63.
近600年来我国的旱灾与瘟疫   总被引:6,自引:0,他引:6  
根据有关历史文献、气象资料、报表和地方志的统计结果 ,15— 19世纪 ,全国共发生旱灾 15次 ,总历时 4 9年 ,其中 14次有瘟疫伴生。北方旱灾 14次 ,13次有瘟疫伴生 ;南方旱灾 7次 ,均有瘟疫伴生 ,有 6次南北同旱。 2 0世纪 ,全国共发生旱灾 18次 ,其中 ,北方旱灾 17次 ,两次有瘟疫伴生 ;南方旱灾 11次 ,1次有瘟疫伴生。 2 0世纪的灾害发生率是前 5 0 0年的 6倍。该文指出 ,这是由于在全球工业化过程中 ,不断增加的温室气体产生了温室效应 ,使气候变暖、降水减少、持续冬暖所致。因此 ,该文建议加快实施西部开发 ,治理环境 ,实施节水、调水工程 ,提高防灾抗灾能力 ,以缓解南北旱灾和瘟疫的发生  相似文献   
64.
To protect public-use microdata, one approach is not to allow users access to the microdata. Instead, users submit analyses to a remote computer that reports back basic output from the fitted model, such as coefficients and standard errors. To be most useful, this remote server also should provide some way for users to check the fit of their models, without disclosing actual data values. This paper discusses regression diagnostics for remote servers. The proposal is to release synthetic diagnostics—i.e. simulated values of residuals and dependent and independent variables–constructed to mimic the relationships among the real-data residuals and independent variables. Using simulations, it is shown that the proposed synthetic diagnostics can reveal model inadequacies without substantial increase in the risk of disclosures. This approach also can be used to develop remote server diagnostics for generalized linear models.  相似文献   
65.
经济系统的演化与政策作用   总被引:1,自引:0,他引:1  
该文根据耗散结构的基本原理 ,将经济系统划分为平衡态、过渡态和自组织状态。并将政策因素看成是一种外部调控手段 ,分析了在经济系统的不同状态下 ,政策因素对改变系统的结构及变化趋势所起的不同作用  相似文献   
66.
This article explores the experiences of asylum seekers who have been housed in Glasgow under the government's dispersal policy. It notes the work of the Audit Commission in identifying those factors which may be considered when assessing the suitability of areas for asylum-seeker settlement. These factors are then discussed in detail in relation to the Glasgow case study, using information derived from interviews with asylum seekers themselves, with service providers and various community and voluntary organizations. The article notes the impact of additional factors such as media coverage, which were not considered by the Audit Commission. The article discusses the appropriateness of cities such as Glasgow, with relatively small minority ethnic populations, as locations for asylum-seeker settlement, and explores the impact of devolution. It concludes by suggesting that areas such as Glasgow may, with the appropriate commitment, become places where asylum seekers may successfully settle, once they have received refugee status, with new multicultural communities being created.  相似文献   
67.
该文分析了法国会计模式的特点和影响因素 ,认为法国会计模式与中国会计模式存在相似之处 ,并借鉴法国 1 996年以来会计改革的经验 ,对完善我国会计模式提出了建议  相似文献   
68.
We consider the problem of density estimation when the data is in the form of a continuous stream with no fixed length. In this setting, implementations of the usual methods of density estimation such as kernel density estimation are problematic. We propose a method of density estimation for massive datasets that is based upon taking the derivative of a smooth curve that has been fit through a set of quantile estimates. To achieve this, a low-storage, single-pass, sequential method is proposed for simultaneous estimation of multiple quantiles for massive datasets that form the basis of this method of density estimation. For comparison, we also consider a sequential kernel density estimator. The proposed methods are shown through simulation study to perform well and to have several distinct advantages over existing methods.  相似文献   
69.
70.
Summary. We propose a simple estimation procedure for a proportional hazards frailty regression model for clustered survival data in which the dependence is generated by a positive stable distribution. Inferences for the frailty parameter can be obtained by using output from Cox regression analyses. The computational burden is substantially less than that of the other approaches to estimation. The large sample behaviour of the estimator is studied and simulations show that the approximations are appropriate for use with realistic sample sizes. The methods are motivated by studies of familial associations in the natural history of diseases. Their practical utility is illustrated with sib pair data from Beaver Dam, Wisconsin.  相似文献   
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