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771.
In this study, we identified unique clusters of parenting behaviors based on parents' school involvement, community involvement, rule‐setting, and cognitive stimulation with data from the Panel Study of Income Dynamics—Child Development Supplement. In early (n=668) and middle adolescence (n=634), parents who provided high cognitive stimulation (i.e., cognitive enrichment parents) or engaged in all parenting behaviors (i.e., engaged parents) had the highest family income, parent education, and percentage of European Americans. Adolescents of cognitive enrichment or engaged parents often evidenced the highest academic and social adjustment. Adolescents whose parents set a large number of rules (i.e., “Rule setters”) or were also heavily involved in the community (i.e., the “Managers” cluster) had the lowest adjustment.  相似文献   
772.
Despite ratification of the United Nations Convention on the Rights of the Child, children remain the only people in Australia against whom violence may be justified as discipline. This article presents findings from qualitative research conducted in the State of Victoria, in which children were invited to contextualise incidents of physical punishment by describing the experience from different standpoints and reflecting on the feelings and motivations of victims and perpetrators. The research provides new insights into children's experiences of childhood ‘discipline’, as children reveal the physical and emotional impact of being hit by a parent, the futility of ‘physical punishment’, parents’ confusing reactions and children's awareness of double standards. Children suggest more positive ways to communicate and to resolve conflict, and provide insightful comments that have the potential to enlighten adults’ thinking about the issue.  相似文献   
773.
Prior research has consistently documented differences between men’s and women’s reactions to being touched by other people. One of the more interesting findings in this literature is the apparent role of marital status in dramatically altering these sex differences in reactions to intimate touch. Unmarried men tend to respond more favorably to intimate touch than unmarried women do, but this difference is reversed among married people. However, research that documented this effect has potentially confounded marital status with age. Participants in this investigation were 305 adults, ranging in age from 18–69. They completed an extensive survey of their reactions to touch to various body regions from a significant other. Results indicated that men had uniformly more positive reactions to intimate touch than women did. For non-intimate touch, the sexes were more comparable in their reactions. This investigation once again documented a disordinal sex by marital status interaction. Unmarried men had generally more positive reactions to touch than unmarried women did and this pattern was reversed among married participants. When statistically controlling for participants’ age, these interactions were still evident.  相似文献   
774.
775.
This paper aimed at comparing the well-being of children across the most economically advanced countries of the world while discussing the methodological issues involved in comparing children’s well-being across countries. A Child Well-being Index was constructed to rank countries according to their performance in advancing child well-being. The Index used 30 indicators combined into 13 components, again summarised in 5 dimensions for 29 rich countries. Data from various sources were combined to capture aspects of child well-being: material well-being, health, education, behaviour and risks, housing and environment. The scores for the countries on all variables and combinations of variables were discussed in detail. The Child Well-being Index revealed that the Netherlands and the Scandinavian countries (excluding Denmark) did relatively better than the other countries while Romania and the United States performed well below the average. Overall, serious differences existed in child well-being across countries suggesting that in many, improvement could be made in the quality of children’s lives.  相似文献   
776.
This paper systematically reviews previous studies of trust from social, economic and technological perspectives and develops a holistic framework for trust, which can be used to analyse the establishment and maintenance of trust in online transactions, and identify the mechanisms that can be used to increase trust. Trust plays a crucial role in the formation of dependent relationships represented by online transactions, and a holistic treatment of trust is necessary because of the gap that exists between the developments in information systems and our understanding of their social and economic implications, and the impact on the perceived trust of the transacting parties. This review enables us to depict an online transaction through its attributes and context, and systematically map these to identified trust antecedents. The key components and processes of the framework are outlined, and three strands of empirical work are discussed to develop it further. The framework highlights the critical role of institutions in the establishment and maintenance of trust in online transactions, which informs the development of e‐commerce and e‐business platforms and the underpinning information systems, and facilitates the establishment of mechanisms to induce additional institutions to increase trust in online transactions.  相似文献   
777.
We illustrate the use of the Mathematica software system (programming language) for performing Bayesian calculations of the sort encountered in introductory presentations of Bayesian statistics. In particular, we show the ease with which one can do numerical computation, graphics, and symbolic computation to analyze one- and two-dimensional probability density functions. Our illustrations involve a time series problem using oxygen uptake data taken from a burn patient.  相似文献   
778.
In statistical practice, rectangular tables of numeric data are commonplace, and are often analyzed using dimension-reduction methods like the singular value decomposition and its close cousin, principal component analysis (PCA). This analysis produces score and loading matrices representing the rows and the columns of the original table and these matrices may be used for both prediction purposes and to gain structural understanding of the data. In some tables, the data entries are necessarily nonnegative (apart, perhaps, from some small random noise), and so the matrix factors meant to represent them should arguably also contain only nonnegative elements. This thinking, and the desire for parsimony, underlies such techniques as rotating factors in a search for “simple structure.” These attempts to transform score or loading matrices of mixed sign into nonnegative, parsimonious forms are, however, indirect and at best imperfect. The recent development of nonnegative matrix factorization, or NMF, is an attractive alternative. Rather than attempt to transform a loading or score matrix of mixed signs into one with only nonnegative elements, it directly seeks matrix factors containing only nonnegative elements. The resulting factorization often leads to substantial improvements in interpretability of the factors. We illustrate this potential by synthetic examples and a real dataset. The question of exactly when NMF is effective is not fully resolved, but some indicators of its domain of success are given. It is pointed out that the NMF factors can be used in much the same way as those coming from PCA for such tasks as ordination, clustering, and prediction. Supplementary materials for this article are available online.  相似文献   
779.
The bootstrap, the jackknife, and classical methods are compared through their confidence intervals for the proportion of affected fetuses in a common type of animal experiment. Specifically, suppose that for the ith of M pregnant animals, there are x i affected fetuses out of n i total in the litter. The conditional distribution of x i given n i is sometimes modeled as binomial (n i p i ), where p i is a realization from some unknown continuous density. The p i are not observable and it is of interest in some toxicological experiments to find confidence intervals for E(p). Theory suggests that the proposed parametric bootstrap should produce higher order agreement between the nominal and actual coverage than that exhibited by the usual nonparametric bootstrap. Some simulation results provide additional evidence of this superiority of the modified parametric bootstrap over the jack-knife and classical approaches. The proposed resampling is flexible enough to handle a more general model allowing correlation between p i and n i .  相似文献   
780.
ABSTRACT

This paper reviews and extends the literature on the finite sample behavior of tests for sample selection bias. Monte Carlo results show that, when the “multicollinearity problem” identified by Nawata (1993 Nawata , K. ( 1993 ). A note on the estimation of models with sample-selection biases . Economics Letters 42 : 1524 . [CSA] [CROSSREF] [Crossref], [Web of Science ®] [Google Scholar]) is severe, (i) the t-test based on the Heckman–Greene variance estimator can be unreliable, (ii) the Likelihood Ratio test remains powerful, and (iii) nonnormality can be interpreted as severe sample selection bias by Maximum Likelihood methods, leading to negative Wald statistics. We also confirm previous findings (Leung and Yu, 1996 Leung , S. F. , Yu , S. ( 1996 ). On the choice between sample selection and two-part models . Journal of Econometrics 72 : 197229 . [CSA] [CROSSREF] [Crossref], [Web of Science ®] [Google Scholar]) that the standard regression-based t-test (Heckman, 1979 Heckman , J. J. ( 1979 ). Sample selection bias as a specification error . Econometrica 47 : 153161 . [CSA] [Crossref], [Web of Science ®] [Google Scholar]) and the asymptotically efficient Lagrange Multiplier test (Melino, 1982 Melino , A. ( 1982 ). Testing for sample selection bias . Review of Economic Studies 49 : 151153 . [CSA] [Crossref], [Web of Science ®] [Google Scholar]), are robust to nonnormality but have very little power.  相似文献   
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