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The effects of group problem-solving method and problem-situation complexity on attempts at implementing group solutions were investigated in a laboratory-field setting. Group members were supervisory nurses from various organizations, who were randomly assigned to three groups in a balanced research design which included three group decision-making processes and three levels of problem-situation complexity in implementation. The dependent variable was the number of attempts at implementing group-derived solutions in home organizations. The results showed that structure in group decision-making processes led to increased rates of implementation attempts at all levels of problem-situation complexity. There was a significant complexity-by-process interaction effect among the decision-making processes, which supports the conclusion that the type of group decision-making process and the problem-situation complexity should be considered in order to optimize the number of implementation attempts.g  相似文献   
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Collaborating researchers used a multi equation model to analyze 3080 mother-infant pairs living on the island of Cebu in the central Philippines and to estimate a child health production function. The econometric methods used eliminated obstacles such as heterogeneity and endogeneity of significant explanatory factors. They also maximized the longitudinal quality of the data. The results showed that morbidity in 1 period reduced infant weight in following periods. For example, diarrhea and febrile respiratory infection reduced growth in the time period following the illnesses. Further effects of some contributing factors were great near birth not diminished with age. For example, breast feeding promoted growth and protected against infection, especially diarrhea and febrile respiratory infection, more substantially near birth than it did later. Further, in urban areas, preventive health care positively affected growth independently of its indirect influence on reducing respiratory infection. Yet it had little effect on diarrhea. Diarrhea had a strong adverse effect on growth. Exposure of the infant to enteric pathogens had the greatest influence on production of diarrhea. In urban areas, exposure included water supply contamination, exposure to feces, a more pathogenic diet, and community crowding. In rural areas, however, exposure included community crowding and increased rainfall which presumably washed feces into the water supply. Household crowding in both urban and rural areas and irritation from smoke in urban areas only tended to bring about febrile respiratory infection.  相似文献   
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"This paper describes the methodology used to incorporate AIDS mortality in recently revised World Bank population projections....The paper first reviews different approaches for projecting AIDS and its demographic consequences. This is followed by a summary of an epidemiological model that simulates the spread of HIV used in this analysis, and a demographic model that translates mortality from AIDS into population outcomes. These models are then used in a set of simulations, from which the effect of current HIV prevalence on projected future mortality is extracted. Finally, the extracted equations linking current HIV prevalence with future mortality indicators are applied to sub-Saharan countries with a measurable level of current HIV prevalence."  相似文献   
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This article examines the external shocks and subsequent adjustment processes in the Soviet Union, China, and Hungary during 1974–76, 1979–81, and 1984–87. It compares the experiences of the three socialist countries with regard to external shocks to those of inward-and outward-oriented groups of newly industrializing countries (NICs). In contrast to the NICs, terms of trade effects were of secondary magnitude to export demand effects of external shocks in the three socialist countries during the first two periods. The oil-exporting Soviet Union had beneficial terms of trade effects during the first two periods, with unfavorable effects coming only in the third period. The adjustment responses to the external shocks varied greatly in the Soviet Union from the other two reform-oriented socialist countries and from both groups of NICs. It is interesting to note that the types of responses in the Soviet Union were quite opposite to that one observes for market economies. However, reform-oriented China and Hungary seemed to have response patterns similar to those of market economies, though China's response was similar to the outward-oriented NICs, while Hungary's was similar to the inward-oriented NICs.The authors would like to thank two anonymous referees, as well as Robert Dernberger, Albert Fishlow, Gregory Grossman, Chung Lee, Michael Plummer, Laura Tyson, and Benjamin Ward, for useful comments on this paper. Research in preparing this study was partly supported by a grant from the Institute of International Studies and Center for Slavic and East European Studies of the University of California, Berkeley.  相似文献   
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Factor models are often used to reduce the complexity of data. It is simple to find common factors and to interpret them. However, it is doubtful whether factor models are always appropriate. Especially when the common factor is considered to be an attitude, it must be stable through time and explain a considerable part of the variances. A procedure is suggested to test the usefulness of a common factor. In an experimental pilot study in which an attitude towards immigrant workers was investigated, the instability and superfluousness of a common factor is shown. An alternative model is presented which suggests that changing opinions can be explained by specific variables. Finally it is shown that a more stable common factor is found if a so-called MIMIC-design is used.  相似文献   
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