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71.
In this article a general result is derived that, along with a functional central limit theorem for a sequence of statistics, can be employed in developing a nonparametric repeated significance test with adaptive target sample size. This method is used in deriving a repeated significance test with adaptive target sample size for the shift model. The repeated significance test is based on a functional central limit theorem for a sequence of partial sums of truncated observations. Based on numerical results presented in this article one can conclude that this nonparametric sequential test performs quite well.  相似文献   
72.
“动词+到L”的“把”字句论析   总被引:1,自引:1,他引:0  
重点讨论了“到L”处在动词之后的“把”字句,从三个不同的角度分析了此类“把”字句的位移类型,认为虽然每一具体句子的位移情况都可以从三个方面来考察,但共现的具体小类有差别,这是因为不同的位移类型与动词的语义特征和类之间存在着相互制约的关系。  相似文献   
73.
Microbiological food safety is an important economic and health issue in the context of globalization and presents food business operators with new challenges in providing safe foods. The hazard analysis and critical control point approach involve identifying the main steps in food processing and the physical and chemical parameters that have an impact on the safety of foods. In the risk‐based approach, as defined in the Codex Alimentarius, controlling these parameters in such a way that the final products meet a food safety objective (FSO), fixed by the competent authorities, is a big challenge and of great interest to the food business operators. Process risk models, issued from the quantitative microbiological risk assessment framework, provide useful tools in this respect. We propose a methodology, called multivariate factor mapping (MFM), for establishing a link between process parameters and compliance with a FSO. For a stochastic and dynamic process risk model of in soft cheese made from pasteurized milk with many uncertain inputs, multivariate sensitivity analysis and MFM are combined to (i) identify the critical control points (CCPs) for throughout the food chain and (ii) compute the critical limits of the most influential process parameters, located at the CCPs, with regard to the specific process implemented in the model. Due to certain forms of interaction among parameters, the results show some new possibilities for the management of microbiological hazards when a FSO is specified.  相似文献   
74.
We consider a model of firm pricing and consumer choice, where consumers are loss averse and uncertain about their future demand. Possibly, consumers in our model prefer a flat rate to a measured tariff, even though this choice does not minimize their expected billing amount—a behavior in line with ample empirical evidence. We solve for the profit‐maximizing two‐part tariff, which is a flat rate if (a) marginal costs are not too high, (b) loss aversion is intense, and (c) there are strong variations in demand. Moreover, we analyze the optimal nonlinear tariff. This tariff has a large flat part when a flat rate is optimal among the class of two‐part tariffs.  相似文献   
75.
Using the universe of large Canadian manufacturing firms in 1988 and 1996, we investigate to what extent outsourcing patterns concord with the predictions of a simple property rights model. The unique availability of disaggregate information on outputs as well as inputs permits the construction of a detailed measure of vertical integration. We rely on five measures of technological intensity to proxy for investments that are likely to be specific to a buyer–seller relationship. A theoretical model that allows for varying degrees of investment specificity and interrelatedness—externalities between buyer and supplier investments—guides the analysis. Property rights predictions on the link between investment intensities and optimal ownership are strongly supported, but only for transactions with low interrelatedness. High specificity and low risk of appropriation strengthen the predictions in the model and in the data.  相似文献   
76.
ABSTRACT: We introduce a class of Toeplitz‐band matrices for simple goodness of fit tests for parametric regression models. For a given length r of the band matrix the asymptotic optimal solution is derived. Asymptotic normality of the corresponding test statistic is established under a fixed and random design assumption as well as for linear and non‐linear models, respectively. This allows testing at any parametric assumption as well as the computation of confidence intervals for a quadratic measure of discrepancy between the parametric model and the true signal g;. Furthermore, the connection between testing the parametric goodness of fit and estimating the error variance is highlighted. As a by‐product we obtain a much simpler proof of a result of 34 ) concerning the optimality of an estimator for the variance. Our results unify and generalize recent results by 9 ) and 15 , 16 ) in several directions. Extensions to multivariate predictors and unbounded signals are discussed. A simulation study shows that a simple jacknife correction of the proposed test statistics leads to reasonable finite sample approximations.  相似文献   
77.
One aspect of successful employee assistance program (EAP) implementation is the adoption of a formal, written policy, reflecting company commitment to EAP guidelines and goals. This study of criteria predictive of such policy adoption was conducted at the occupational alcoholism project of a New England health maintenance organization (HMO). Data on nearly 400 organizations contacted by occupational program consultants (OPCs) over a 20-month period were collected by questionnaire and interview. One third of these organizations adopted employee assistance policies and set about establishing formal programs. Stepwise multiple regression is the principal method used to pinpoint the correlates of policy adoption. Two of the most important of these are the attitudes of contact persons within the organization toward alcoholism and employee assistance programs, particularly their admission of alcohol problems within their social networks; and the consultants' persistence and marketing skills. The adopting organizations also had reputations for being progressive, and actively concerned about employee welfare; they tended to be large, their executives autonomous, and their union membership rates high. Inhibiting policy acceptance were fears that a written policy would jeopardize the reputation and image of the organization, and that an employee assistance program would remove internal control of personal procedures. The adequacy of the evaluative data and methods are discussed, and recommendations are offered in the interests of streamlining the efforts of OPCs and of achieving greater penetration of targeted organizations.  相似文献   
78.
中介语和反馈在外语学习中的作用   总被引:1,自引:0,他引:1  
二语习得者在学习过程中不可避免地出现许多错误,这不仅是可以容忍的,而且是有益的。改正错误则是学习者的“中介语”向目的语趋近的一种方法。本文将对中介语的发展进行讨论,并从“反馈”这一角度来阐述它对外语教学的影响。  相似文献   
79.
张学良西北开发思想及其启示   总被引:1,自引:0,他引:1  
张学良不仅是一位爱国将军,一位民族英雄,也是中国现代化建设的先驱。早在20世纪30年代,他就提出开发西北的一些设想,认为开发西北是复兴中国的基础,开发西北要革除私心,一致动员,借鉴美国的西部开发,同时要注意交通、环境、民族等问题。这些设想虽在当时由于缺乏现实条件难以实现,但是其现代化建设思想的重要组成部分,对今天的西部大开发仍有借鉴意义。  相似文献   
80.
辣椒常规品种子叶诱导植株再生体系的建立   总被引:4,自引:0,他引:4  
以辣椒常规品种保加利亚尖椒与赤研6号为材料,探讨了激素、苗龄、有机成分、AgNO3等因素对子叶再生的影响.观察到PD添加剂对常规品种辣椒离体子叶不定芽的诱导分化及伸长有明显的促进作用.保加利亚尖椒的子叶分化频率达到100%,赤研6号的分化频率达到83%.芽伸长率分别为75%与55%,生根率达到80%以上.建立了辣椒常规品种的子叶离体高效再生体系.  相似文献   
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