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971.
We consider the square contingency tables which arise when the same method of classification is applied twice. The hypothesis of marginal homogeneity is then relevant! and can be tested by various methods Models are discussed which contain marginal homogeneity as a special case. They include a class based on univariate and bivariate Dirichlet distributions. The question of ordered categories is briefly discussed. Applications are made to data on unaided distance vision. 相似文献
972.
A measure of multicollinearity is defined which is useful in evaluating maintained hypotheses and aiding estimator selection as it suggests when a non-traditional estimator proposed by Bock (1975) is minimax and dominates ordinary least squares. An example is used to illustrate the presented methodology. 相似文献
973.
William B. Lacy 《Sociological focus》2013,46(3):203-216
Abstract College student value change was analyzed for individual and group value accentuation or convergence among a longitudinal panel study of students in a traditional, large liberal arts college and a small, innovative living-learning subenvironment. Initially students in the innovative environment were more liberal, socally conscious, culturally sophisticated and intellectually oriented than their counterparts in the traditional setting, and, after two years, accentuation of these group differences had occurred. However, these group differences were not the result of accentuation of individual differences. Instead, increases in the student values were linked to interaction with peers and faculty on related topics and these patterns of interaction were more likely to occur in the living-learning subenvironment. Finally, those students who initially were lowest on a value and who frequently interacted with faculty or peers on related topics tended to experience the greatest value change. 相似文献
974.
975.
976.
Poduri S.R.S. Rao 《统计学通讯:理论与方法》2013,42(15):1659-1669
The MINQUE and its modifications are considered for estimating the variances of the balanced one-way random effects model. The effects of the a priori values on the estimators of the variances are examined in detail. The Mean Square Errors of the estimators are compared for variations in the prior values of the unknown variances. 相似文献
977.
Lisa Rapp-Paglicci Chris Stewart William Rowe 《Journal of social service research》2013,39(3):309-319
ABSTRACT Self-regulation skills programs focusing on emotional regulation and executive functioning and arts programs have separately demonstrated reductions in internalizing and externalizing disorders and academic difficulties and have shown improvement in self-regulation skills. This study sought to evaluate participants in Prodigy (a program synthesizing arts and self-regulation skills) regarding changes in mental health symptoms and academic performance. A quasi-experimental pretest–posttest was conducted with 108 at-risk adolescents and their parents. Significant reductions in internalizing and externalizing mental health symptoms and increases in academic self-efficacy with positive trends in improved academic achievement were noted. Future research regarding the potential of these two modalities is discussed. 相似文献
978.
Abstract We specify a revised model of the demographic transition which accounts for national fertility levels and changes over the past two decades. The model includes cultural, geographic, demographic and family planning program variables, in addition to a measure of national socio-economic modernization. Using crude birth rates for 117 countries, we operationalize and then apply the revised model to 1974 rates, and then test a longitudinal model of 1955–59 to 1974 change in rates. A final model for 81 less developed nations from the original set of 117 countries includes a measure of family planning program effort. Including this highly significant measure in a model of 1955–59 to 1974 change results in further evidence favoring modification of the traditional demographic transition model. Implications for the future course of fertility in underdeveloped countries are discussed. 相似文献
979.
Final assembly plants send material schedules to first-tier suppliers who in turn send schedules to second-tier suppliers and so on through the multiple tiers of the supply chain. A key cost driver for the supply chain is a schedule characteristic termed stability. The Total Quality Management approach is applied to improve schedule stability in the supply chain of a large vertically integrated automotive manufacturer. A measurement described, actual stability results are provided, the causes of instability are listed, and some corrective actions are specified. Results indicate that schedule stability can be improved without damaging the performance of other measures such as inventory and customer responsiveness. and analysis process is 相似文献
980.
In this paper, we link production planning decisions to marketing decisions that involve the price of product groups. The focus of this paper is the development of a closed-loop procedure for aggregate production planning and pricing. We seek to satisfy uncertain demand while minimizing total costs that include material, labour, and inventory holding costs. The procedure is useful for variable demand to update short-term aggregate plans. 相似文献