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71.
Relations between self-reported parental reactions to children's negative emotions (PNRs) and children's socially appropriate/problem behavior and negative emotionality were examined longitudinally. Evidence was consistent with the conclusion that relations between children's externalizing (but not internalizing) emotion and parental punitive reactions to children's negative emotions are bidirectional. Reports of PNRs generally were correlated with low quality of social functioning. In structural models, mother-reported problem behavior at ages 10-12 was at least marginally predicted from mother-reported problem behavior, children's regulation, and parental punitive or distress reactions. Moreover, parental distress and punitive reactions at ages 6-8 predicted reports of children's regulation at ages 8-10, and regulation predicted parental punitive reactions at ages 10-12. Father reports of problem behavior at ages 10-12 were predicted by earlier problem behavior and parental distress or punitive reactions; some of the relations between regulation and parental reactions were similar to those in the models for mother-reported problem behavior. Parental perceptions of their reactions were substantially correlated over 6 years. Some nonsupportive reactions declined in the early to mid-school years, but all increased into late childhood/early adolescence.  相似文献   
72.
This paper examines the factors affecting the performance of global query expansion based on term co-occurrence data and suggests a way to maximize the retrieval effectiveness. Major parameters to be optimized through experiments are term similarity measure and the weighting scheme of additional terms. The evaluation of four similarity measures tested in query expansion reveal that mutual information and Yule's Y, which emphasize low frequency terms, achieve better performance than cosine and Jaccard coefficients that have the reverse tendency. In the evaluation of three weighting schemes, similarity weight performs well only with short queries, whereas fixed weights of approximately 0.5 and similarity rank weights were effective with queries of any length. Furthermore, the optimal similarity rank weight achieving the best overall performance seems to be the least affected by test collections and the number of additional terms. For the efficiency of retrieval, the number of additional terms needs not exceed 70 in our test collections, but the optimal number may vary according to the characteristics of the similarity measure employed.  相似文献   
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Externalities as conventionally defined miss many of the spillovers that are both causes and consequences of the technological changes that underlie economic growth. We introduce a much wider concept called technological complementarities. New general purpose technologies (GPTs) rejuvenate the growth process by creating technological complementarities, which are adequately measured neither by total factor productivity (TFP) nor by externalities. There would be major gains from technological change even if the returns on capital invested in innovation never exceeded the returns on investing in existing technologies so that there were neither externalities nor positive changes in TFP.  相似文献   
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Three aspects of the ‘most important problem’ questionused in agenda-setting research to measure issue salience amongthe public were examined. A split-ballot design in a state-widesurvey compared versions of the public agenda with a socialframe of reference versus a personal frame of reference, versionsusing the traditional term ‘problem’ versus ‘issue’,and the effects of question order. High correlations betweenthe different versions were found in all three sets of comparisons.  相似文献   
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SYNOPSIS

Parental working is not unambiguously beneficial for children. On the one hand, working parents can be positive role models for their children, and income can improve children’s lives in many ways. On the other hand, work can impair parent-child interactions, especially when the parents experience high levels of working stress. In my commentary, I conclude that the paper by River, enjoys strong support for the impact of maternal state anxiety (attachment anxiety) and work-interfering-with-family (WIF)-conflict related guilt on parents behaviors. Considering the cognitive-relational stress-theory by Lazarus and Folkman, the balance of personal resources and external demands can explain parental stress, which could be associated with parental behavior. Full-time-working parents, who experience high levels of guilt and report high levels of attachment anxiety, are more prone to show low levels of stress resistance toward crying infants. However, these associations are not studied in families with high risk factors. Furthermore, future studies should include aspects of mental health status in a theoretical model. Taken together, the target article provides a solid foundation for further research. I also propose to transfer the findings into more realistic research setting, which includes high-risk groups (parents with low socioeconomic status, low-income, mental health problems) to study how infant cry can influence parents’ patterns of care and abuse. The commentary tries to enrich the study by including Fraiberg’s “ghosts in the nursery” to further integrating parental mentalizing processes in the model explaining parents’ reactions to infant cry signal in the context of WIF conflicts.  相似文献   
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