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31.
Despite strong political commitment, actual gains in improving accountability in development co‐operation have been limited. Main reasons for this include the low level of transparency and high number of actors, as well as the limitations of the self‐reported and input‐oriented OECD reporting system. Efforts through the International Aid Transparency Initiative (IATI) and related transparency initiatives are ill‐equipped to change this given their decision to adhere to the same system. This article uses the specific area of support to capacity development to illustrate this. While further disaggregation of reporting on technical co‐operation could respond to a transparency gap, overcoming the accountability gap requires moving beyond promoting ‘supply‐side’ reform and re‐engaging in efforts to promote collective action.  相似文献   
32.
The international field placement is a site of both identity confusion and identity development for the social work student. Aiming to develop their professional identity they are faced with a challenge: the presence of two dominant identities, the tourist identity and the student identity. Whilst the embodiment of the tourist identity has often facilitated the student’s motivation to undertake the placement experience, the student identity is what both university staff and agency field educators perceive as integral to student engagement in this remote educational setting. Social work educators perceive this identity challenge as an impediment to learning. In contrast, students report feeling that their tourist traits strengthened their personal and professional capacity, natural curiosity and ability to engage with the local community. By analysing the roles of university staff as liaison support, and field educators as agency supervisors, it is possible to explore a teaching and learning relationship that is student-centred, grounded in the immersive international experience. Through privileging the student’s voice social work educators involved with organising, supporting and supervising international field placements are able to understand the placement as a continuum of learning. On this continuum identity reconciliation is viewed as a crucial element in the development of a professional identity.  相似文献   
33.
One-sided confidence regions for continuous cumulative distribution function are constructed using empirical cumulative distribution functions and the generalized Kolmogorov-Smirnov distance. The band width of such regions becomes narrower in the right or left tail of the distribution. Significance levels necessary for implementation are given. Some other K-S type distances useful in constructing a confidence region with nonconstant width are also included.  相似文献   
34.
Clinical phase II trials in oncology are conducted to determine whether the activity of a new anticancer treatment is promising enough to merit further investigation. Two‐stage designs are commonly used for this situation to allow for early termination. Designs proposed in the literature so far have the common drawback that the sample sizes for the two stages have to be specified in the protocol and have to be adhered to strictly during the course of the trial. As a consequence, designs that allow a higher extent of flexibility are desirable. In this article, we propose a new adaptive method that allows an arbitrary modification of the sample size of the second stage using the results of the interim analysis or external information while controlling the type I error rate. If the sample size is not changed during the trial, the proposed design shows very similar characteristics to the optimal two‐stage design proposed by Chang et al. (Biometrics 1987; 43:865–874). However, the new design allows the use of mid‐course information for the planning of the second stage, thus meeting practical requirements when performing clinical phase II trials in oncology. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
35.
The popular generalized extreme value (GEV) distribution has not been a flexible model for extreme values in many areas. We propose a generalization – referred to as the Kumaraswamy GEV distribution – and provide a comprehensive treatment of its mathematical properties. We estimate its parameters by the method of maximum likelihood and provide the observed information matrix. An application to some real data illustrates flexibility of the new model. Finally, some bivariate generalizations of the model are proposed.  相似文献   
36.
Nuria Torrado 《Statistics》2017,51(6):1359-1376
Stochastic ordering relations between extreme order statistics from exponential, Weibull and gamma distributions have been studied extensively by many researchers in recent years. In this work, we obtain various ordering results for the comparisons of two extreme order statistics from scale models when one set of scale parameters majorizes the other. The new results obtained here are applied when the baseline distributions are exponentiated Weibull or generalized gamma distributions. In this way, we generalize and extend some results established recently in the literature.  相似文献   
37.
针对经管类专业学生统计学学习中重应用、轻理论的现状,在教学中融入模型思想,通过规范统计学中参数估计、假设检验、方差分析等几类问题的数学模型建立,加强学生对统计学问题的理解和学习。  相似文献   
38.
Comparisons of best linear unbiased estimators with some other prominent estimators have been carried out over the last 50 years since the ground breaking work of Lloyd [E.H. Lloyd, Least squares estimation of location and scale parameters using order statistics, Biometrika 39 (1952), pp. 88–95]. These comparisons have been made under many different criteria across different parametric families of distributions. A noteworthy one is by Nagaraja [H.N. Nagaraja, Comparison of estimators and predictors from two-parameter exponential distribution, Sankhyā Ser. B 48 (1986), pp. 10–18], who made a comparison of best linear unbiased (BLUE) and best linear invariant (BLIE) estimators in the case of exponential distribution. In this paper, continuing along the same lines by assuming a Type II right censored sample from a scaled-exponential distribution, we first compare BLUE and BLIE of the exponential mean parameter in terms of Pitman closeness (nearness) criterion. We show that the BLUE is always Pitman closer than the BLIE. Next, we introduce the notions of Pitman monotonicity and Pitman consistency, and then establish that both BLUE and BLIE possess these two properties.  相似文献   
39.
Let T2 i=z′iS?1zi, i==,…k be correlated Hotelling's T2 statistics under normality. where z=(z′i,…,z′k)′ and nS are independently distributed as Nkp((O,ρ?∑) and Wishart distribution Wp(∑, n), respectively. The purpose of this paper is to study the distribution function F(x1,…,xk) of (T2 i,…,T2 k) when n is large. First we derive an asymptotic expansion of the characteristic function of (T2 i,…,T2 k) up to the order n?2. Next we give asymptotic expansions for (T2 i,…,T2 k) in two cases (i)ρ=Ik and (ii) k=2 by inverting the expanded characteristic function up to the orders n?2 and n?1, respectively. Our results can be applied to the distribution function of max (T2 i,…,T2 k) as a special case.  相似文献   
40.
This paper establishes a nonparametric estimator for the treatment effect on censored bivariate data under unvariate censoring. This proposed estimator is based on the one from Lin and Ying(1993)'s nonparametric bivariate survival function estimator, which is itself a generalized version of Park and Park(1995)' quantile estimator. A Bahadur type representation of quantile functions were obtained from the marginal survival distribution estimator of Lin and Ying' model. The asymptotic property of this estimator is shown below and the simulation studies are also given  相似文献   
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