The Anderson-Darling test of fit for the power-law distribution from left-censored samples

Maximum likelihood estimation and a test of fit based on the Anderson-Darling statistic are presented for the case of the power-law distribution when the parameters are estimated from a left-censored sample. Expressions for the maximum likelihood estimators and tables of asymptotic percentage points for the A² statistic are given. The technique is illustrated for data from the Dow Jones Industrial Average index, an example of high theoretical and practical importance in Econophysics, Finance, Physics, Biology and, in general, in other related sciences such as Complexity Sciences.     

A power law distribution in patients’ lengths of stay in hospital

The distribution of patients’ lengths of stay in English hospitals is measured by using routinely collected data from 11 years. It is found to be well approximated by a power law distribution spanning over more than three decades. To explain this observation, a theoretical resource allocation model is presented. It is based on iterative long-term scheduling of hospital beds, and its main assumption is that future beds are allocated preferentially. This represents a situation where different parts of the health care system compete for resources, with bargaining powers proportional to current resource levels.     

有重弹性体形变与质量分布规律的简明推导

依据胡克定律与串联弹性体的劲度系数计算公式,直观简便地导出了弹性体在重力场中的形变规律、质量分布规律及其质心位置.     

HL-2A装置ECRH的微波强度分布测量与分析

利用红外热像仪测量微波传播路径上的三个不同距离截平面上的微波强度分布,计算出辐射图的一阶及二阶矩并重建相位信息,可以确定微波波束的强度分布和准直度。使用该方法对两套ECRH系统传输线进行了定量的分析,获得了微波强度分布均为高斯分布、7m 3^#传输线的微波束线准直度为0.05°、6m 4^#传输线微波束线准直度为0.14°的结果。