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91.
The mean residual life measures the expected remaining life of a subject who has survived up to a particular time. When survival time distribution is highly skewed or heavy tailed, the restricted mean residual life must be considered. In this paper, we propose an additive–multiplicative restricted mean residual life model to study the association between the restricted mean residual life function and potential regression covariates in the presence of right censoring. This model extends the proportional mean residual life model using an additive model as its covariate dependent baseline. For the suggested model, some covariate effects are allowed to be time‐varying. To estimate the model parameters, martingale estimating equations are developed, and the large sample properties of the resulting estimators are established. In addition, to assess the adequacy of the model, we investigate a goodness of fit test that is asymptotically justified. The proposed methodology is evaluated via simulation studies and further applied to a kidney cancer data set collected from a clinical trial.  相似文献   
92.
Menarche, the onset of menstruation, is an important maturational event of female childhood. Most of the studies of age at menarche make use of dichotomous (status quo) data. More information can be harnessed from recall data, but such data are often censored in a informative way. We show that the usual maximum likelihood estimator based on interval censored data, which ignores the informative nature of censoring, can be biased and inconsistent. We propose a parametric estimator of the menarcheal age distribution on the basis of a realistic model of the recall phenomenon. We identify the additional information contained in the recall data and demonstrate theoretically as well as through simulations the advantage of the maximum likelihood estimator based on recall data over that based on status quo data.  相似文献   
93.
In this paper, the problem of constant partially accelerated life tests when the lifetime follows the generalized exponential distribution is considered. Based on progressive type-II censoring scheme, the maximum likelihood and Bayes methods of estimation are used for estimating the distribution parameters and acceleration factor. A Monte Carlo simulation study is carried out to examine the performance of the obtained estimates.  相似文献   
94.
It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived. In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included.  相似文献   
95.
审查基准是行政法规审查制度的重要组成部分,它不仅规定了行政法规合法性审查之宽严程度,也限定了审查机关之权限范围。根据我国宪法与立法法之规定,全国人民代表大会常务委员会对行政法规之审查以"合法性"为基准。这种"合法性"审查基准在行政法规制定权限审查、行政法规内容审查以及审查程序等方面遭遇现实难题,并因此净化了行政法规审查制度的现实效果,为此,有必要引借"合理性"审查基准,并借此推动我国行政法规审查制度的完善。  相似文献   
96.
通过7×5不完全双列杂交,分析了几个新恢复系、不育系及其杂交组合10个观察性状的一段配合力、特殊配合力、总配合力效应和小区产量的遗传效应。大多数性状的一段配合力比特殊配合力具有更大的相对重要性,结实率主要受特殊配合力控制。总配合力效应与性状平均值至高度正相关。产量的杂种优势主要来源于基因分散,遗传效应中以加性效应最大,显性效应次之,上位性和胞质效应也有一定的影响。  相似文献   
97.
ABSTRACT

The Rayleigh distribution is proposed to be the underlying model from which observables are to be predicted by using Bayesian approach. Progressively Type-II censored data from the Rayleigh distribution is considered and the two-sample prediction technique is used. Numerical computations and a simulation are given to illustrate the performance of the procedures.  相似文献   
98.
Consider a positive random variable of interest Y depending on a covariate X, and a random observation time T independent of Y given X. Assume that the only knowledge available about Y is its current status at time T  : δ=I{YT}δ=I{YT} with II the indicator function. This paper presents a procedure to estimate the conditional cumulative distribution function F of Y given X   from an independent identically distributed sample of (X,T,δ)(X,T,δ).  相似文献   
99.
Outsourcing has been a key policy tool for delivering a range of social services, and regarded as more effective than insourcing or direct government provision. At the same time, it has also caused many delivery issues such as principal‐agent problems, a lack of policy coordination, and poor‐quality welfare services. While the pendulum continues to swing between insourcing and outsourcing, we aim to propose a new public–private partnership model called the “hybrid insourcing model” and examine which factors influence the performance of the model. In South Korea, around 2010, the local government in Namyangju City was the first to implement the “Hope Care Center model,” a kind of hybrid insourcing model, which has been praised for its innovation and widely emulated by central and local governments. Our analysis utilizes data collected between December 2017 and January 2018 from public sector employees and civilian staff in Namyangju and a comparable city, A. From this, we draw a number of implications, both for theory and for policy. We argue that, for public–private partnerships, active cooperation and equality are the biggest factors in contributing to positive performance. These work alongside leaders with a clear vision and with employees' positive attitude.  相似文献   
100.
In comparing two treatments with failure time observations, confidence bands for the "difference" of two survival curves provide useful information about a global picture of the treatment difference over time. In this note, we propose a rather simple procedure for constructing such simultaneous confidence intervals. Our technique can also be used in the one-sample case, which has been extensively studied in the literature.  相似文献   
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