柏拉图与亚里士多德生成论之比较

柏拉图在《蒂迈欧》和“未成文学说”中所讨论的生成理论与亚里士多德的生成论有很大的相关性,甚至可以说后者是在与前者的对话中形成的。无论是三本原的生成模式学说,火、气、水、土四元素相互生成学说,还是由四元素生成同质体的理论,甚至个别事物的生成理论,亚里士多德都从老师那里获取了理论资源。本文即从这几个方面进行对比论证,表明亚里士多德继承和发展了柏拉图的生成理论。本文还就柏拉图的“接受者”与亚里士多德的最初质料和终极质料的关系进行了进一步的澄清。     

Every Minute Counts: Using Process Improvement and Performance Feedback to Improve Patient Flow in an Emergency Department

Prolonged emergency department (ED) visits are associated with a number of adverse outcomes for patients as well as lower patient satisfaction scores and increased costs. Several factors that influence the length of ED visits are out of the control of hospital employees, but some opportunities exist to improve performance. For this study, the ED department of a 150-bed hospital in the southeastern United States wanted to improve door-to-discharge time. To do so, a subprocess of door-to-discharge time was targeted, door-to-order. After analyzing the process, the team created standard orders for the 10 most common presenting conditions in the ER with preapproval, allowing nurses to submit the orders without the provider first visiting the patient. Following the process change, daily feedback was added to increase utilization of the preapproved orders. Reductions in door-to-order times and door-to-discharge were observed and patient satisfaction remained stable. Implications for future research in this area are discussed.     

Characterizations based on order statistics under sampling without replacement

In this paper, we consider finite populations and investigate their characterizations by regressions of order statistics under sampling without replacement. We also investigate some asymptotic results when the size of the population goes to infinity.     

Inference of non-centrality parameter of a truncated non-central chi-squared distribution

Non-central chi-squared distribution plays a vital role in statistical testing procedures. Estimation of the non-centrality parameter provides valuable information for the power calculation of the associated test. We are interested in the statistical inference property of the non-centrality parameter estimate based on one observation (usually a summary statistic) from a truncated chi-squared distribution. This work is motivated by the application of the flexible two-stage design in case–control studies, where the sample size needed for the second stage of a two-stage study can be determined adaptively by the results of the first stage. We first study the moment estimate for the truncated distribution and prove its existence, uniqueness, and inadmissibility and convergence properties. We then define a new class of estimates that includes the moment estimate as a special case. Among this class of estimates, we recommend to use one member that outperforms the moment estimate in a wide range of scenarios. We also present two methods for constructing confidence intervals. Simulation studies are conducted to evaluate the performance of the proposed point and interval estimates.     

Classification rules for triply multivariate data with an AR(1) correlation structure on the repeated measures over time

In this article we study the problem of classification of three-level multivariate data, where multiple q$q$-variate observations are measured on u$u$-sites and over p$p$-time points, under the assumption of multivariate normality. The new classification rules with certain structured and unstructured mean vectors and covariance structures are very efficient in small sample scenario, when the number of observations is not adequate to estimate the unknown variance–covariance matrix. These classification rules successfully model the correlation structure on successive repeated measurements over time. Computation algorithms for maximum likelihood estimates of the unknown population parameters are presented. Simulation results show that the introduction of sites in the classification rules improves their performance over the existing classification rules without the sites.     

Optimum covariate designs in partially balanced incomplete block (PBIB) design set-ups

The use of covariates in block designs is necessary when the covariates cannot be controlled like the blocking factor in the experiment. In this paper, we consider the situation where there is some flexibility for selection in the values of the covariates. The choice of values of the covariates for a given block design attaining minimum variance for estimation of each of the parameters has attracted attention in recent times. Optimum covariate designs in simple set-ups such as completely randomised design (CRD), randomised block design (RBD) and some series of balanced incomplete block design (BIBD) have already been considered. In this paper, optimum covariate designs have been considered for the more complex set-ups of different partially balanced incomplete block (PBIB) designs, which are popular among practitioners. The optimum covariate designs depend much on the methods of construction of the basic PBIB designs. Different combinatorial arrangements and tools such as orthogonal arrays, Hadamard matrices and different kinds of products of matrices viz. Khatri–Rao product, Kronecker product have been conveniently used to construct optimum covariate designs with as many covariates as possible.     

Semiparametric estimation for count data through weighted distributions

This paper is concerned with semiparametric discrete kernel estimators when the unknown count distribution can be considered to have a general weighted Poisson form. The estimator is constructed by multiplying the Poisson estimate with a nonparametric discrete kernel-type estimate of the Poisson weight function. Comparisons are then carried out with the ordinary discrete kernel probability mass function estimators. The Poisson weight function is thus a local multiplicative correction factor, and is considered as the uniform measure to detect departures from the equidispersed Poisson distribution. In this way, the effects of dispersion and zero-proportion with respect to the standard Poisson distribution are also minimized. This method of estimation is also applied to the weighted binomial form for the count distribution having a finite support. The proposed estimators, in addition to being simple, easy-to-implement and effective, also outperform the competing nonparametric and parametric estimators in finite-sample situations. Two examples illustrate this new semiparametric estimation.     

世界的多线发展与中国的发展路径创新

本文以马克思的辩证唯物史观为武器,多角度、多层面、大跨度地分析了现实中还不够标准的社会主义的历史发展模式,研究了中国社会主义初级阶段内涵的发展子阶段和市场经济本质。