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poisson回归在职业队列研究中的应用

中国卫生统计 1996年第1期13卷 6-9页

作者：宇传华余松林向惠云陈俊群第四军医大学卫生统计学教研室同济医科大学卫生统计学教研室湖北省襄樊棉纺织印染厂卫生处

本文介绍Ｐｏｉｓｓｏｎ回归模型及其计算方法，运用这一方法对某职业人群队列研究死亡资料作了Ｐｏｉｓｓｏｎ回归分析。研究结果提示该厂可能有某些职业危害因素存在，影响了职工寿命。

关键词：死亡职业队列研究回归分析 poisson

One-Sample Bayesian Predictive Analyses for an Exponential Non-Homogeneous poisson Process in Software Reliability

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Open Journal of Statistics 2014年第5期4卷 402-411页

作者： Albert Orwa Akuno Luke Akong’o Orawo Ali Salim Islam Department of Mathematics Egerton University Egerton Kenya

The Goel-Okumoto software reliability model, also known as the Exponential Nonhomogeneous poisson Process,is one of the earliest software reliability models to be proposed. From literature, it is evident that most of the study that has been done on the Goel-Okumoto software reliability model is parameter estimation using the MLE method and model fit. It is widely known that predictive analysis is very useful for modifying, debugging and determining when to terminate software development testing process. However, there is a conspicuous absence of literature on both the classical and Bayesian predictive analyses on the model. This paper presents some results about predictive analyses for the Goel-Okumoto software reliability model. Driven by the requirement of highly reliable software used in computers embedded in automotive, mechanical and safety control systems, industrial and quality process control, real-time sensor networks, aircrafts, nuclear reactors among others, we address four issues in single-sample prediction associated closely with software development process. We have adopted Bayesian methods based on non-informative priors to develop explicit solutions to these problems. An example with real data in the form of time between software failures will be used to illustrate the developed methodologies.

关键词： Nonhomogeneous poisson Process Non-Informative Priors Software Reliability Models Bayesian Approach

Using poisson Modeling and Queuing Theory to Optimize Staffing and Decrease Patient Wait Time in the Emergency Department

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Open Journal of Emergency Medicine 2018年第3期6卷 54-72页

作者： Geralda Xavier Joseph Crane Michele Follen Wendy Wilcox Steven Pulitzer Chuck Noon Kings County Hospital Brooklyn NY USA Haslam College of Business University of Tennessee Knoxville TN USA Teamhealth Inc. Knoxville TN USA

Introduction: Studies have shown Emergency Department (ED) crowding contributes to reduced quality of patient care, delays in starting treatments, and increased number of patients leaving without being seen. This analysis shows how to theoretically and optimally align staffing to demand. Methods: The ED value stream was identified and mapped. Patients were stratified into three resource-driven care flow cells based on the severity indices. Time observations were conducted for each of the key care team members and the manual cycle times and service rate were calculated and stratified by severity indices. Using X32 Healthcare’s Online Staffing Optimization (OSO) tool, staffing inefficiencies were identified and an optimal schedule was created for each provider group. Results: Lower Severity Indices (higher acuity patient) led to longer times for providers, nurses, patient care assistants, and clerks. The patient length of stay varied from under one hour to over five hours. The flow of patients varied considerably over the 24 hours’ period but was similar by day of the week. Using flow data, we showed that we needed more nurses, more care team members during peak times of patient flow. Eight hour shifts would allow better flexibility. We showed that the additional salary hours added to the budget would be made up for by increased revenue recognized by decreasing the number of patients who leave without being seen. Conclusion: If implemented, these changes will improve ED flow by using lean tools and principles, ultimately leading to timeliness of care, reduced waits, and improved patient experience.

关键词： poisson Modeling Queuing Theory Reduced Waits Improved Patient Experience

Analysis on Sixth-Order Compact Approximations with Richardson Extrapolation for 2D poisson Equation

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Journal of Applied Mathematics and Physics 2018年第6期6卷 1139-1159页

作者： Ruxin Dai Pengpeng Lin Department of Computer Science and Information Systems University of Wisconsin River Falls River Falls WI USA Department of Mathematics Statistics and Computer Science University of Wisconsin Stout Menomonie WI USA

By using Richardson extrapolation and fourth-order compact finite difference scheme on different scale grids, a sixth-order solution is computed on the coarse grid. Other three techniques are applied to obtain a sixth-order solution on the fine grid, and thus give out three kinds of Richardson extrapolation-based sixth order compact computation methods. By carefully analyzing the truncation errors respectively on 2D poisson equation, we compare the accuracy of these three sixth order methods theoretically. Numerical results for two test problems are discussed.

关键词： Richardson Extrapolation Sixth-Order Solutions High Order Compact Finite Difference Scheme Truncation Error Analysis 2D poisson Equation

The Exact Formulation of the Inverse of the Tridiagonal Matrix for Solving the 1D poisson Equation with the Finite Difference Method

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Journal of Electromagnetic Analysis and Applications 2014年第10期6卷 303-308页

作者： Serigne Bira Gueye Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

A new method for solving the 1D poisson equation is presented using the finite difference method. This method is based on the exact formulation of the inverse of the tridiagonal matrix associated with the Laplacian. This is the first time that the inverse of this remarkable matrix is determined directly and exactly. Thus, solving 1D poisson equation becomes very accurate and extremely fast. This method is a very important tool for physics and engineering where the poisson equation appears very often in the description of certain phenomena.

关键词： 1D poisson Equation Finite Difference Method Tridiagonal Matrix Inversion Thomas Algorithm Gaussian Elimination Potential Problem

Comparison of Ruin Probabilities in Compound poisson Risk Model

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Open Journal of Statistics 2019年第1期9卷 41-47页

作者： Dol Nath Khanal Mathematics Faculty Otero Junior College La Junta USA

Compound poisson risk model has been simulated. It has started with exponential claim sizes. The simulations have checked for infinite ruin probabilities. An appropriate time window has been chosen to estimate and compare ruin probabilities. The infinite ruin probabilities of two-compound poisson risk process have estimated and compared them with standard theoretical results.

关键词： Compound poisson Risk Model Ruin Probabilities Comparison Simulations Theoretical Results

Generalization of the Exact Solution of 1D poisson Equation with Robin Boundary Conditions, Using the Finite Difference Method

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Journal of Electromagnetic Analysis and Applications 2014年第12期6卷 372-381页

作者： Serigne Bira Gueye Kharouna Talla Cheikh Mbow Département de Physique Faculté des Sciences et Techniques Université Cheikh Anta Diop Dakar-Fann Sénégal

A new and innovative method for solving the 1D poisson Equation is presented, using the finite differences method, with Robin Boundary conditions. The exact formula of the inverse of the discretization matrix is determined. This is the first time that this famous matrix is inverted explicitly, without using the right hand side. Thus, the solution is determined in a direct, very accurate (O(h2)), and very fast (O(N)) manner. This new approach treats all cases of boundary conditions: Dirichlet, Neumann, and mixed. Therefore, it can serve as a reference for solving the poisson equation in one dimension.

关键词： Robin Boundary poisson Equation Matrix Inversion

Asymptotic Comparison of Method of Moments Estimators and Maximum Likelihood Estimators of Parameters in Zero-Inflated poisson Model

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Applied Mathematics 2012年第6期3卷 610-616页

作者： G. Nanjundan T. Raveendra Naika Department of Statistics Bangalore University Bangalore India Maharani’s Science College for Women Bangalore India

This paper discusses the estimation of parameters in the zero-inflated poisson (ZIP) model by the method of moments. The method of moments estimators (MMEs) are analytically compared with the maximum likelihood estima... 详细信息

关键词： Zero-Inflated poisson Model Maximum Likelihood and Moment Estimators EM Algorithm Asymptotic Relative Efficiency

Two-Sample Bayesian Predictive Analyses for an Exponential Non-Homogeneous poisson Process in Software Reliability

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Open Journal of Statistics 2014年第9期4卷 742-750页

作者： Albert Orwa Akuno Luke Akong’o Orawo Ali Salim Islam Department of Mathematics Egerton University Egerton Kenya

The Goel-Okumoto software reliability model is one of the earliest attempts to use a non-homogeneous poisson process to model failure times observed during software test interval. The model is known as exponential NHPP model as it describes exponential software failure curve. Parameter estimation, model fit and predictive analyses based on one sample have been conducted on the Goel-Okumoto software reliability model. However, predictive analyses based on two samples have not been conducted on the model. In two-sample prediction, the parameters and characteristics of the first sample are used to analyze and to make predictions for the second sample. This helps in saving time and resources during the software development process. This paper presents some results about predictive analyses for the Goel-Okumoto software reliability model based on two samples. We have addressed three issues in two-sample prediction associated closely with software development testing process. Bayesian methods based on non-informative priors have been adopted to develop solutions to these issues. The developed methodologies have been illustrated by two sets of software failure data simulated from the Goel-Okumoto software reliability model.

关键词： Nonhomogeneous poisson Process Software Reliability Models Non-Informative Priors Bayesian Approach