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133.
This analysis investigates the assertion that the baby-boom cohorts, by virtue of their large size and new lifecourse redistribution tendencies, are likely to initiate significant shifts in the distribution of the elderly population as these cohorts enter into the 65-and-older age categories. The author contends that cohorts' pre-elderly lifecourse migration patterns should be incorporated into studies of elderly population distribution shifts. 2 questions are addressed: will the new lifecourse migration patterns provide for a more deconcentrated redistribution of the baby-boom cohorts, both prior to and after their entry into the elderly age categories, than the lifecourse migration patterns followed by earlier cohorts; and will the new lifecourse distribution pattern lead, in the long run, to a significantly more deconcentrated distribution of the elderly population. The examination of these 2 questions focuses, largely, on redistribution across 9 broad regional and metropolitan area groupings defined on the basis of 3 census regions -- the North (combining the Northeast and Midwest census regions), the South, and the West -- and 3 categories of metropolitan status -- large metropolitan areas (those with 1980 populations exceeding 1 million), other metropolitan areas, and nonmetropolitan areas. The comparison of "new" versus "old" lifecourse migration patterns contrasts the census-based age-specific migration stream rates, registered over the 1975-80 period, with those registered over the 1965-70 period. Given the sharp and broad-based shift toward deconcentrated redistribution which characterized practically all segments of the population during the 1970s, it is assumed that the age-specific migration patterns observed over the 1975-80 period approximate the more deconcentrated redistribution tendencies which will be adopted by the baby-boom cohorts (and their successors) over the remainder of their lifecourse. The 1965-70 net migration rates point up the aggregate redistribution implications associated with the "old" lifecourse migration stream patterns. Among the rates for North large metropolitan areas, the only positive net migration is observed for the 25-29 age category; the greatest net outmigration rate is shown for the 65-69 age category. The rates for South nonmetropolitan areas are negative for all age categories under age 55, and most accentuated outmigration is shown during the young-adult years. The positive net migration exhibited for the older adult and post retirement ages reflects the low outmigration rates from nonmetropolitan areas during these ages and the slight peaking of immigration for these years. The results of this analysis imply that more attention should be devoted to migration, over the entirety of the lifecourse, in future studies of population redistribution.  相似文献   
134.
In this paper, we discuss the properties of preliminary test estimators (PTE) of the parameters of simple linear model with measurement error (ME model) when the slope of the linear model is suspected to be zero. Expressions of the bias, MSE and efficiencies are obtained under conditional as well as unconditional situations with known reliability coefficient. Conditional model results are compared to the standard model without measurement error. We also provide the unconditional model analysis in finite samples. Asymptotic theory under local alternatives is developed when the variance of measurement error or the ratio of the variance of the model error relative to the variance of the measurement error is known. Asymptotic expressions of bias and MSE of the estimators along with their efficiencies are obtained. In every case, it is shown that the measurement error tend to increase the variability of the estimators compared to the estimators without measurement error. Graphs and tables are provided to see these results and to determine optimum level of significance for minimum guaranteed efficiency. Received October 2001 RID="*" ID="*"  A. K. Md. E. Saleh is a Distinguished Research Professor and H. M. Kim is a Ph.D. candidate in the School of Mathematics and Statistics, Carleton University, Ottawa. Acknowledgment. The authors gratefully acknowledge the constructive suggestion of the referees to improve the paper. The research is supported by NSERC grant A3088.  相似文献   
135.
This study explores the effects of task structure and leader power on participative leadership across Australian, African, Papua-New Guinea and Pacific Island managers. Managers in all national groups are more participative in situations of low structure and low power than for high structure and high power, respectively. Participation in situations of low structure and low power declines in the order: Australia, Africa, Papua-New Guinea, Pacific Islands. It is argued that this effect is an instrumental effect of managerial education, rather than being culturally determined. the Vroom-Yetton leadership methodology is used to measure participation levels. Subjects are a total of 150 middle-level managers attending management education courses.  相似文献   
136.
Abstract: The working wife as a factor in the determination of family status has been universally ignored by students of stratification. In this plea for investigation, it is suggested that the employment or married women could affect the system of stratification in the following ways: (1) making possible greater access to symbols of status; (2) implying that the husband has been unsuccessful in his own career; (3) identifying the wife with a particular occupation; and (4) identifying certain occupations with wives of high status.  相似文献   
137.
Sample design and sample allocation methods are developed for random digit dialling in household telephone surveys. The proposed method is based on a two-way stratification of telephone numbers. A weighted probability proportional to size sample allocation technique is used, with auxiliary variables about the telephone coverage rates, within local telephone exchanges of each substrata. This makes the sampling design nearly “self-weighting” in residential numbers when the prior information is well assigned. A computer program generates random numbers for the local areas within the existing phone capacities. A simulation study has shown greater sample allocation gain by the weighted probabilities proportional to size measures over other sample allocation methods. The amount of dialling required to obtain the sample is less than for proportional allocation. A decrease is also observed on the gain in sample allocation for some methods through the increasing sample sizes.  相似文献   
138.
Progressive stress accelerated life tests under finite mixture models   总被引:1,自引:0,他引:1  
In this paper, progressive stress accelerated life tests are considered when the lifetime of a product under use condition follows a finite mixture of distributions. The experiment is performed when each of the components in the mixture follows a general class of distributions which includes, among others, the Weibull, compound Weibull, power function, Gompertz and compound Gompertz distributions. It is assumed that the scale parameter of each component satisfies the inverse power low, the progressive stress is directly proportional to time and the cumulative exposure model for the effect of changing stress holds. Based on type-I censoring, the maximum likelihood estimates (MLEs) of the parameters under consideration are obtained. A special attention is paid to a mixture of two Rayleigh components. Simulation results are carried out to study the precision of the MLEs and to obtain confidence intervals for the parameters involved.  相似文献   
139.
We investigated U.S. and Canadian reactions to workplace drug and alcohol testing programs. Canadian truck drivers (n = 183) deemed drug and alcohol testing policies less fair, and were less accepting of these policies, than their American counterparts (n = 153). We also compared the perspectives of recipients versus third-party observers with regard to their reactions to a drug testing program. Unlike the pattern observed among American observers, the responses by Canadian observers were highly similar to those of the recipients. Canadian observers were more inclined to file a formal protest regarding the implementation of a drug and alcohol testing program than were U.S. observers. The results also showed that procedural and interactional justice principles contributed to the program's fairness, acceptance, and lower levels of protest intentions in both Canada and the United States. We propose that scholars and practitioners can gain a better understanding of multinational reactions to drug and alcohol testing by considering not only cultural but also historical, social, political, and other environmental factors that can shape reactions to personnel practices.  相似文献   
140.
In this paper we present an effective algorithm for the construction and the identification of two-level nonisomorphic orthogonal arrays. Using this algorithm, we identify and list a full catalogue of nonisomorphic orthogonal arrays with parameters OA(24,7,2,t), OA(28,6,2,t) and OA(32,6,2,t), t ≥ 2. Some statistical properties of these designs are also considered.  相似文献   
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