A likelihood ratio test to discriminate exponential–Poisson and gamma distributions

The exponential–Poisson (EP) distribution with scale and shape parameters β>0 and λ∈?, respectively, is a lifetime distribution obtained by mixing exponential and zero-truncated Poisson models. The EP distribution has been a good alternative to the gamma distribution for modelling lifetime, reliability and time intervals of successive natural disasters. Both EP and gamma distributions have some similarities and properties in common, for example, their densities may be strictly decreasing or unimodal, and their hazard rate functions may be decreasing, increasing or constant depending on their shape parameters. On the other hand, the EP distribution has several interesting applications based on stochastic representations involving maximum and minimum of iid exponential variables (with random sample size) which make it of distinguishable scientific importance from the gamma distribution. Given the similarities and different scientific relevance between these models, one question of interest is how to discriminate them. With this in mind, we propose a likelihood ratio test based on Cox's statistic to discriminate the EP and gamma distributions. The asymptotic distribution of the normalized logarithm of the ratio of the maximized likelihoods under two null hypotheses – data come from EP or gamma distributions – is provided. With this, we obtain the probabilities of correct selection. Hence, we propose to choose the model that maximizes the probability of correct selection (PCS). We also determinate the minimum sample size required to discriminate the EP and gamma distributions when the PCS and a given tolerance level based on some distance are before stated. A simulation study to evaluate the accuracy of the asymptotic probabilities of correct selection is also presented. The paper is motivated by two applications to real data sets.     

Inference for quantile measures of kurtosis,peakedness, and tail weight

Insight into measures of peakedness, heavy-tailedness, and kurtosis can be gained by studying Ruppert’s ratios of interquantile ranges. They are not only monotone in Horn’s measure of peakedness when applied to the central portion of the population, but also monotone in the practical tail-index of Morgenthaler and Tukey, when applied to the tails. Non-parametric confidence intervals are found for Ruppert’s ratios, and sample sizes required to obtain such intervals for a pre-specified relative width and level are provided. In addition, the empirical power of distribution-free tests for peakedness and bimodality are found for some symmetric distributions.     

Testing Wagner's Law in India: A cointegration and causality analysis

The present study empirically analyzes the validity of Wagner's Law for Indian economy. With the use of annual time series data from 1970–71 to 2013–14, all the six versions of Wagner's Law have been analyzed to test the relationship between government expenditure and gross domestic product. Wagner's Law states that the economic growth is the causative factor of the growth of the public expenditure. The study applied the unit root test and cointegration test to find the long-run relationship between government expenditure and gross domestic product. The present study employed the various econometric techniques such as unit root test, cointegration, and causality analysis for empirical analysis. The empirical analysis under study inferred mixed results of Wagner's Law for Indian economy, where four versions, namely Peacock, Gupta, Guffman, and Musgrave, found valid for Indian economy. The study concluded that the Wagner's Law is valid for the Indian economy except the Pryor and Mann Versions of the Wagner's Law.     

皖北地区旅游业发展制约因素的个案研究

皖北地区旅游业是安徽省旅游业发展的短板，要实现皖北旅游业快速发展就要深究皖北旅游业发展缓慢的症结所在。本文选取淮北市作为调查点，从主客观方面分析了制约淮北市旅游业发展的因素并提出解决对策，以此为皖北旅游业发展提供借鉴。     

政治过程视角下的执政党实现人民利益能力建设

实现人民利益有利于执政党的长期执政，而能否实现好人民利益，又要依靠党的执政，依靠党的实现人民利益能力的不断提升。从人民利益实现过程分析，党实现人民利益的能力主要包涵人民利益表达能力、综合能力、决策能力、执行能力以及反馈能力。现阶段执政党要提高实现人民利益能力，需要进一步加强思想建设、组织建设、作风建设以及制度建设，不断开创党的建设这一伟大工程的新局面。     

Young People Leaving Care: Participatory Research to Improve Child Welfare Practices and the Rights of Children and Young People

Abstract

This paper discusses participatory research with young people who are leaving public care in Finland to begin independent lives. The aim of the research, organised by SOS Children's Villages International, was to bring about change in alternative care arrangements, particularly those involving young people's transition to independence. The project used a participatory research design based on employing care-leaving peers as co-researchers. This paper adheres to the methodological principles of empowerment in analysing the personal experiences of young people leaving alternative care with the goal of informing good practice. The findings suggest that the peer research method can be an effective means of empowering young people to develop research skills and to be involved in knowledge production, as well as serving as a means of promoting improved services for “care-leavers”, those young people who are leaving either foster care or institutional care. The participatory and peer research method challenges the traditional understandings of expertise and knowledge production. Although the hierarchy between adult researchers and young people as co-researchers is still evident, the method provides possibilities for better understanding the social- and health-service systems and their challenges and pitfalls from a user's perspective.     

《三国演义》在明清时期的传播对民族精神的影响研究

《三国演义》是我国"四大古典小说之一,其在明清时期的广泛传播对中华民族精神产生了不可或缺的深远影响:树立了集"忠义"和"神勇"于一身的崇拜偶像—关羽,提升了民族笃信好义精神,提高了民族凝聚力,增强了民族忧患意识。     

80后农民工的城市就业现状与对策建议

分析了80后农民工在城市的就业特征,主要从四方面提出了对策建议:建立健全80后农民工就业的社会保障机制;改革创新80后农民工就业培训模式;为农民工塑造良好的工作环境;构建农民工双向流迁就业体系。     

浅析社会困境

社会困境是指那些使得个体理性导致集体非理性的环境。文章介绍了社会困境在两人和多人环境下的具体含义,详细说明了解决社会困境的可能途径,即动机性、策略性和结构性解决方法。     

The empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior under Stein's loss function

For the hierarchical Poisson and gamma model, we calculate the Bayes posterior estimator of the parameter of the Poisson distribution under Stein's loss function which penalizes gross overestimation and gross underestimation equally and the corresponding Posterior Expected Stein's Loss (PESL). We also obtain the Bayes posterior estimator of the parameter under the squared error loss and the corresponding PESL. Moreover, we obtain the empirical Bayes estimators of the parameter of the Poisson distribution with a conjugate gamma prior by two methods. In numerical simulations, we have illustrated: The two inequalities of the Bayes posterior estimators and the PESLs; the moment estimators and the Maximum Likelihood Estimators (MLEs) are consistent estimators of the hyperparameters; the goodness-of-fit of the model to the simulated data. The numerical results indicate that the MLEs are better than the moment estimators when estimating the hyperparameters. Finally, we exploit the attendance data on 314 high school juniors from two urban high schools to illustrate our theoretical studies.