Exponentiated Chen distribution: Properties and estimation

This article addresses various properties and estimation methods for the Exponentiated Chen distribution. Although, our main focus is on estimation from frequentist point of view, yet, some statistical and reliability characteristics for the model are derived. We briefly describe different estimation procedures, namely, the method of maximum likelihood estimation, percentile estimation, least square and weighted least-square estimation, maximum product of spacings estimation, Cramér-von-Mises estimation, Anderson–Darling, and right-tail Anderson–Darling estimation. Monte Carlo simulations are performed to compare the performances of the proposed methods of estimation for both small and large samples. Finally, the potentiality of the model is analyzed by means of three real datasets.     

Which factors explain the decline in infant and child mortality in Matlab,Bangladesh?

Infant and child mortality rates have decreased substantially in Matlab, Bangladesh, as they have in many developing areas. We use data from the Matlab Demographic Surveillance System on nearly 94,000 singleton live births that occurred between 1987 and 2002 to investigate the extent to which the change in mortality over this period can be explained by changes in reproductive patterns and socio-economic characteristics. We estimate Cox proportional hazards models for four subperiods of infancy and childhood. Changes over time in reproductive patterns (maternal age, parity, and pregnancy spacing) and in the socio-economic characteristics we consider (e.g. maternal education, SES) explain between 10 and 40% of the decline in mortality rates. Changes in maternal education explain the largest portion of the reduction in infant and child mortality over time that we are able to explain, followed by reductions in the incidence of short interpregnancy intervals. In the other direction, decreases in fertility over time led to increases in the proportion of births that were first births, putting upward pressure on mortality.

Change PP plot and continous sample quantile function

Functional inference recommends data analysis of a sample of n observations by functional and graphical representations of its probability models using various functions on 0 < u < 1, including the quantile function. This paper discusses: charge PP plots and a continuous version of the sample quantile function which use the mid-distinct value probability integral transform; comparison density functions; comparison interpretation of probability integral transform; maximum spacings method of one sample parameter estimation.     

Improved estimation of the stable laws

Fitting general stable laws to data by maximum likelihood is important but difficult. This is why much research has considered alternative procedures based on empirical characteristic functions. Two problems then are how many values of the characteristic function to select, and how to position them. We provide recommendations for both of these topics. We propose an arithmetic spacing of transform variables, coupled with a recommendation for the location of the variables. It is shown that arithmetic spacing, which is far simpler to implement, closely approximates optimum spacing. The new methods that result are compared in simulation studies with existing methods, including maximum-likelihood. The main conclusion is that arithmetic spacing of the values of the characteristic function, coupled with appropriately limiting the range for these values, improves the overall performance of the regression-type method of Koutrouvelis, which is the standard procedure for estimating general stable law parameters.     

Understanding the effects of siblings on child mortality: evidence from India

Given the intrinsically sequential nature of childbirth, timing of a child’s birth has consequences not only for itself but also for its older and younger siblings. The paper argues that prior spacing and posterior spacing between consecutive siblings are thus important measures of intensity of sibling competition for limited parental resources. While the available estimates of child mortality tend to ignore the endogeneity of sibling composition, we use a correlated recursive model of prior and posterior spacing and child mortality to correct it. There is evidence that uncorrected estimates under-estimate the effects of prior and posterior spacing on child mortality.

On the consistency of the maximum spacing method

The main result of this paper is a consistency theorem for the maximum spacing method, a general method of estimating parameters in continuous univariate distributions, introduced by Cheng and Amin (J. Roy. Statist. Soc. Ser. A 45 (1983) 394–403) and independently by Ranneby (Scand. J. Statist. 11 (1984) 93–112). This main result generalizes a theorem of Ranneby (Scand. J. Statist. 11 (1984) 93–112). Also, some examples are given, which shows that this estimation method works also in cases where the maximum likelihood method breaks down.     

以晚育为杠杆,平稳向二孩政策过渡

目前取消生育间隔政策而允许生二孩条件不变的弊远大于利 ,其中最大的弊端在于它实际上是为生育政策平稳调整设置障碍。目前取消只适用于少数人的间隔政策 ,而作出牺牲最大、流引产与被罚风险最大的大多数一孩夫妇的权益得不到改善 ,而且在为一孩夫妇的权益改善 (即生育政策调整 )设置障碍 ,实际上是一种社会不公。晚育是一根有力的“杠杆” ;运用好了 ,可以在国家能够承受的“人口增量”范围内 ,实现平稳向二孩政策过渡的软着陆。     

长江下游地区挖入式港池口门宽度的计算方法

受长江航道的自然地形水深和南京长江大桥通航净空的限制,港口物流服务的腹地纵向延伸和广域化辐射受到较大阻碍,因此,在长江下游河段新建的港口宜尽量兼备承接上游来船转运出海的功能和由海轮转驳江轮的功能。现行规范对于挖入式港池宽度已有较为详细的规定,但对于船舶进出于两码头之间的挖入式港池口门宽度还没有明确的规定和要求,从航道角度出发,引入航行漂角和偏航角概念,着力于阐述船舶进出于两码头之间的挖入式港池口门宽度的计算确定方法。     

A Note on the Fisher Information in Exponential Distribution

ABSTRACT

It is known that the Fisher information in any set of order statistics can be simplified to a sum of double integrals. In this article, we show that it can be further simplified to a sum of single integrals for the scale parameter of an exponential distribution. Moreover, we use the result and provide a simple method of obtaining the optimal spacing of order statistics.