洗衣机发展预测模型及应用

我国洗衣机的生产发展十分迅速,从1978年的年产400台到1985年的883万台,八年间增长二千多倍,今后的生产发展前景如何?运用本文介绍的一种预测模型,可以求得公元2000年以前每年洗衣机需求量的预测值,并求得1983年8月至1991年1月为洗衣机生产发展的成熟时期,该模型亦可用于其它耐用消费品的生产发展预测,所得结果可供有关部门决策时参考。     

Questions and Answers

In addition to his contributions to biostatistics and clinical trials, Paul Meier had a long-term interest in the legal applications of statistics. As part of this, he had extensive experience as a statistical consultant. Legal consulting can be a minefield, but as a result of his background, Paul had excellent advice to give to those starting out on how to function successfully in this environment.     

Analysis of accelerated life tests with weibull failure distribution via generalized linear models

Efficient industrial experiments for reliability analysis of manufactured goods may consist in subjecting the units to higher stress levels than those of the usual working conditions. This results in the so called "accelerated life tests" where, for each pre-fixed stress level, the experiment ends after the failure of a certain pre-fixed proportion of units or a certain test time is reached. The aim of this paper is to determine estimates of the mean lifetime of the units under usual working conditions from censored failure data obtained under stress conditions. This problem is approached through generalized linear modelling and related inferential techniques, considering a Weibull failure distribution and a log-linear stress-response relationship. The general framework considered has as particular cases, the Inverse Power Law model, the Eyring model, the Arrhenius model and the generalized Eyring model. In order to illustrate the proposed methodology, a numerical example is provided.     

Hazard functions and life distributions in discrete time

The problem of studying lifelength distributions in discrete time is considered for certain forms of hazard functions. A class of life distributions that consists of the geometric, the Waring and the negative hypergeometric distributions is shown to result when the hazard function is inversely proportional to some linear function of time.     

Discrete adaptive design in attribute life testing

Properties of a discrete adaptive design in attribute life testing situation are studied. It is shown that the design is strongly consistent and asymptotically normal. Some examples are discussed to show that the design could be used in a wide range of ields, Finally, we give some simulation results to compare the discrete adaptive desigin with some continuous optimal designs.     

Effect of a new selection procedure on adaptive estimation

Adaptive estimation of parameters of some failure time distributionsis considered. A new procedure named the F-procedure has beendeveloped for selecting an appropriate model out of two possible models by Pandey et.al. (1991). Applying this F-procedure adaptive estimatorsof parameters of exponential, Wei bull, inverse Gaussian (IG) and Wald failure time distributions have been proposed in this paper. Comparison of these estimators has been undertaken with MLE's of the respective parameters and with some previous adaptiveestimators by simulation of samples using the Monte Carlo method.Adaptive estimation of parameters of some failure time distributions is considered. A new procedure named the F-procedure has been developedfor selecting an appropriate model out of two possible models by Pandey et.al. (1991). Applying this F-procedure adaptive estimators of parameters of exponential, Wei bull, inverse Gaussian (IG) and Wald failure time distributions have been proposed in this paper. Comparison of these estimators has been undertaken with MLE's of the respective parameters and with some previous adaptive estimators by simulation of samples using the Monte Carlo method.     

Setting the clock back to zero property of a class of bivariate life distributions

In a previous paper. B. R. Rao and Talwalker (1993) considered absolutely continuous life distributions and extended the Lack of Memory Property (L.M.P.) of the exponential distribution and showed that several classes of life distributions have this property, which was called the 'setting the clock back to zero' property. ¶Its analog is discussed in the present paper for hivariate and multivariate classes of life distributions. As a simple application of this analog, it is proved that the Life expectancy and the Percentile Residual Life vectors of a population of individuals under the influence of multiple competing risks have simple expressions if the class of their joint life distributions has the setting the clock back to zero property,     

浅析民众注重口头传承英雄史诗《岭·格萨尔王传》的缘由

本文主要从《格萨尔王传》接受者的角度 ,探讨这部英雄史诗在藏民族中盛传不衰的原因 ,提出了一种新的思路和新的方法。     

试论《格萨尔王传》中古代藏族先民的自然保护意识

自古以来,藏族与大自然和谐相处,以独特的方式保护着大自然,进而产生了独特的自然保护意识和生态意识,深心地影响着世世代代的藏族人民。通过藏族英雄史诗《格萨尔王传》可窥探古代藏族先民对自己生活的环境——大自然的朦胧认识、崇拜到竭力保护这一过程,本文阐述了人类不是大自然的主宰者,人类与自然和谐相处,均衡互利,人与自然和谐发展才是永恒的主题与朴素观念。     

Life Satisfaction of Rural Migrant Workers in Urban China: The Roles of Community Service Participation and Identity Integration

Abstract

China is home to approximately 245 million rural-to-urban migrant workers. The influx of migrants into urban areas has posed various challenges for local social service systems. Recently, increasing number of community services have been developed to meet the growing service demands from the migrant population. However, whether increase in community service use results in improved wellbeing among migrant workers remains critically unexplored. As such, this study examines the role of community service use in migrant workers’ life satisfaction and the potential mediating effect of identity integration in Shenzhen, China. Bootstrapped models were adopted to examine relationship among variables. Drawing from a sample of 1,087 rural-to-urban migrant workers, we found that community service use is positively correlated with both identity integration and migrant workers’ life satisfaction. Moreover, identity integration served as a partial mediator between community service use and life satisfaction. The mediating effect of identity integration was found to increase with age. This study highlights that diverse services should be implemented to address divergent needs of migrants in different age groups. Community service can also serve as a vehicle to foster integration among migrant workers in host communities, especially for older age groups. Future studies may further investigate the relationships between community social capital, community social support, quality of community-based organization and frequency of service use so as to optimize the life satisfaction of migrant workers.