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81.
This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new result is used to study functional summaries for log Gaussian Cox processes.  相似文献   
82.
This article deals with the estimation of R = P{X < Y}, where X and Y are independent random variables from geometric and exponential distribution, respectively. For complete samples, the MLE of R, its asymptotic distribution, and confidence interval based on it are obtained. The procedure for deriving bootstrap-p confidence interval is presented. The UMVUE of R and UMVUE of its variance are derived. The Bayes estimator of R is investigated and its Lindley's approximation is obtained. A simulation study is performed in order to compare these estimators. Finally, all point estimators for right censored sample from the exponential distribution, are obtained.  相似文献   
83.
In many industrial and natural phenomena, we need the probability that a component is smaller than the other component. Under a stress–strength model, this is reliability of an item. Under independent setup, there are different approaches for the estimation of such reliability. Here, estimation is considered under the dependent case. Under bi-variate setup uniformly minimum variance unbiased estimator is obtained. Also comparison with available estimator based on Maximum Likelihood Estimate (MLE) is done through Mean Square Error (MSE) and bias. Also these are compared by computing L1 distance between their distribution functions. From this idea and numerical computations, UMVUE appears to be good.  相似文献   
84.
Many nonparametric tests in one sample problem, matched pairs, and competingrisks under censoring have the same underlying permutation distribution. This article proposes a saddlepoint approximation to the exact p-values of these tests instead of the asymptotic approximations. The performance of the saddlepoint approximation is assessed by using simulation studies that show the superiority of the saddlepoint methods over the asymptotic approximations in several settings. The use of the saddlepoint to approximate the p-values of class of two sample tests under complete randomized design is also discussed.  相似文献   
85.
Two approximations recovering the functions from their transformed moments are proposed. The upper bounds for the uniform rate of convergence are derived. In addition, the comparisons of the estimates of the cumulative distribution function and its density function with the empirical distribution and the kernel density estimates are conducted via a simulation study. The plots of recovered functions are presented for several examples as well.  相似文献   
86.
The aim of this paper is to propose methods of detecting change in the coefficients of a multinomial logistic regression model for categorical time series offline. The alternatives to the null hypothesis of stationarity can be either the hypothesis that it is not true, or that there is a temporary change in the sequence. We use the efficient score vector of the partial likelihood function. This has several advantages. First, the alternative value of the parameter does not have to be estimated; hence, we have a procedure that has a simple structure with only one parameter estimation using all available observations. This is in contrast with the generalized likelihood ratio-based change point tests. The efficient score vector is used in various ways. As a vector, its components correspond to the different components of the multinomial logistic regression model’s parameter vector. Using its quadratic form a test can be defined, where the presence of a change in any or all parameters is tested for. If there are too many parameters one can test for any subset while treating the rest as nuisance parameters. Our motivating example is a DNA sequence of four categories, and our test result shows that in the published data the distribution of the four categories is not stationary.  相似文献   
87.
The Frisch–Waugh–Lovell (FWL) (partitioned regression) theorem is essential in regression analysis. This is partly because it is quite useful to derive theoretical results. The lasso regression and the ridge regression, both of which are penalized least-squares regressions, have become popular statistical techniques. This article describes that the FWL theorem remains valid for these penalized least-squares regressions. More precisely, we demonstrate that the covariates corresponding to unpenalized regression parameters in these penalized least-squares regression can be projected out. Some other results related to the FWL theorem in such penalized least-squares regressions are also presented.  相似文献   
88.
En Israël, les comités d'entreprise s'adaptent à l'économie néolibérale et aux évolutions qui en découlent sur le marché du travail en admettant de plus en plus le recours aux emplois atypiques, tout en essayant de lutter contre ce nouvel avatar de l'économie capitaliste pour protéger les droits des travailleurs. Tiraillés entre ces deux positions, ils sont pris dans un transitoire qui dure, une «liminalité» permanente, qui réduit leur rôle à la recherche de compromis et de solutions circonstancielles. La résistance aux effets pervers des formes d'emploi atypiques reste donc circonscrite et dispersée, ce qui conforte encore les pratiques en question.  相似文献   
89.
流行病学研究表明2型糖尿病(type 2 diabetes mellitus T2DM)能够增加患者发生阿尔茨海默病(Alzheimer's disease,AD)的风险。进一步的分子机制研究也表明,胰岛素抵抗以及胰岛素缺乏,这个T2DM特征性和最主要的发病机制也在AD的发病机制中发挥着重要作用。近年来甚至有人提议将AD称作"3型糖尿病"。基于这些研究,降糖药物也许是治疗AD的一个新选择。大量的临床试验研究也已经表明AD患者能够从降糖药物中获益,本文将主要介绍胰岛素、二甲双胍、噻唑烷二酮类药物以及胰升糖素样多肽1类似物。  相似文献   
90.
利用Schauder不动点定理、自同胚和紧凸子集的相关性质研究Feigenbaum型泛函方程的连续可微解的存在性和唯一性.  相似文献   
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