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91.
Varying-coefficient models are very useful for longitudinal data analysis. In this paper, we focus on varying-coefficient models for longitudinal data. We develop a new estimation procedure using Cholesky decomposition and profile least squares techniques. Asymptotic normality for the proposed estimators of varying-coefficient functions has been established. Monte Carlo simulation studies show excellent finite-sample performance. We illustrate our methods with a real data example.  相似文献   
92.
Empirical Bayes estimates of the local false discovery rate can reflect uncertainty about the estimated prior by supplementing their Bayesian posterior probabilities with confidence levels as posterior probabilities. This use of coherent fiducial inference with hierarchical models generates set estimators that propagate uncertainty to varying degrees. Some of the set estimates approach estimates from plug-in empirical Bayes methods for high numbers of comparisons and can come close to the usual confidence sets given a sufficiently low number of comparisons.  相似文献   
93.
We consider the problem of modelling a long-memory time series using piecewise fractional autoregressive integrated moving average processes. The number as well as the locations of structural break points (BPs) and the parameters of each regime are assumed to be unknown. A four-step procedure is proposed to find out the BPs and to estimate the parameters of each regime. Its effectiveness is shown by Monte Carlo simulations and an application to real traffic data modelling is considered.  相似文献   
94.
As a critical community resource, the senior centre has provided older Americans with a wide array of recreational, nutritional, health, and social service programmes. Funding resources include the Older Americans Act allocations, local organisations and governments, national charities, voluntary associations, and religious associations. The types of programmes offered at a senior centre reflect two models: social agency model or voluntary organisation model. The five most popular programmes are nutrition, health and fitness, recreation, volunteering, and social services. Participation in senior centre activities has positive impacts on the overall well-being of older adult participants. With the rapid growth in the ageing population and improved life expectancy in China, senior centres may serve as a focal point for Chinese older adults by providing a broad spectrum of social services to enhance the well-being of community-dwelling older adults, to support their independence and dignity, and to facilitate ageing in place in later life.  相似文献   
95.
There have been a number of procedures used to analyze non-monotonic binary data to predict the probability of response. Some classical procedures are the Up and Down strategy, the Robbins–Monro procedure, and other sequential optimization designs. Recently, nonparametric procedures such as kernel regression and local linear regression (llogr) have been applied to this type of data. It is a well known fact that kernel regression has problems fitting the data near the boundaries and a drawback with local linear regression is that it may be “too linear” when fitting data from a curvilinear function. The procedure introduced in this paper is called local logistic regression, which fits a logistic regression function at each of the data points. An example is given using United States Army projectile data that supports the use of local logistic regression when analyzing non-monotonic binary data for certain response curves. Properties of local logistic regression will be presented along with simulation results that indicate some of the strengths of the procedure.  相似文献   
96.
We investigate the convergence rates of uniform bias-corrected confidence intervals for a smooth curve using local polynomial regression for both the interior and boundary region. We discuss the cases when the degree of the polynomial is odd and even. The uniform confidence intervals are based on the volume-of-tube formula modified for biased estimators. We empirically show that the proposed uniform confidence intervals attain, at least approximately, nominal coverage. Finally, we investigate the performance of the volume-of-tube based confidence intervals for independent non-Gaussian errors.  相似文献   
97.
Political reform after the departure of President Soeharto’s New Order (1966–1998) provided opportunities for previously oppressed social groups to express their concerns and to demand fair recognition. The results of this newly found freedom have been quite immediately visible in Jakarta, where social and political institutions spearheaded by Chinese originally sprouted. In the regions, political participation of ethnic Chinese has also grown; significantly in those regions with a large Chinese population. In West Kalimantan, the number of Chinese being elected to local parliaments in some regions has doubled. They have also contested numerous direct local executive elections since 2003 and have been successful in winning four posts: a mayor, a district head, a deputy district head, and a deputy governor. By looking at the case of West Kalimantan, this article will examine the factors behind the growth in Chinese political activism, the factors contributing to the success of Chinese candidates in elections, how the Chinese have influenced local and provincial politics, and the challenges they are facing.  相似文献   
98.
The skew-generalized-normal distribution [Arellano-Valle, RB, Gómez, HW, Quintana, FA. A new class of skew-normal distributions. Comm Statist Theory Methods 2004;33(7):1465–1480] is a class of asymmetric normal distributions, which contains the normal and skew-normal distributions as special cases. The main virtues of this distribution is that it is easy to simulate from and it also supplies a genuine expectation–maximization (EM) algorithm for maximum likelihood estimation. In this paper, we extend the EM algorithm for linear regression models assuming skew-generalized-normal random errors and we develop a diagnostics analyses via local influence and generalized leverage, following Zhu and Lee's approach. This is because Cook's well-known approach would be more complicated to use to obtain measures of local influence. Finally, results obtained for a real data set are reported, illustrating the usefulness of the proposed method.  相似文献   
99.
When sampling from a continuous population (or distribution), we often want a rather small sample due to some cost attached to processing the sample or to collecting information in the field. Moreover, a probability sample that allows for design‐based statistical inference is often desired. Given these requirements, we want to reduce the sampling variance of the Horvitz–Thompson estimator as much as possible. To achieve this, we introduce different approaches to using the local pivotal method for selecting well‐spread samples from multidimensional continuous populations. The results of a simulation study clearly indicate that we succeed in selecting spatially balanced samples and improve the efficiency of the Horvitz–Thompson estimator.  相似文献   
100.
学前教育地方立法是我国学前教育立法体系的有机组成部分,截至2020 年1 月,我国现行有效的学前教育地方性法规 规章共61 部,呈现出立法时间跨度大,立法主体覆盖面广,立法模式体例多样等特征。地方立法一定程度上规范着地方学前 教育的有序开展,但也存在部分省市立法机关对当地学前教育立法关注度不高、部分立法难以满足当前学前教育发展需求、表 达不规范、可操作性欠佳、缺乏地方特色以及冲突与越位等问题。对此,应从科学确定学前教育地方立法内容、建立地方性法 律适时更新制度、健全学前教育地方立法调研制度、加强地方立法专业化制度建设等方面予以优化。  相似文献   
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