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61.
This paper examines local authority social workers' decision‐making when considering referrals of children, where the concerns are on the margin of child protection procedures. In doing so, it describes the findings of a qualitative research study undertaken in the policy context of attempts to ‘refocus’ social work practice in the late 1990s and early twenty‐first century. Data collection involved interviews with social workers and parents in 23 cases. Conclusions are that referrals were evaluated on the basis of five key factors, specificity, severity, risk, parental accountability and corroboration, the use of which determined whether an initial assessment or an investigation of alleged abuse took place. The analysis builds on previous work in the child protection field, but demonstrates how the application of these factors differs between cases of child concern and cases of child protection. Policy implications concern the complexity of decision‐making in the uncertain context of limited referral information and it is proposed that the simplistic notion of a continuum of abuse is now outdated. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
62.
Mothers' time‐use patterns were compared in families in which infants spent more than 30 hours per week in child care (In‐Care group; n= 143) versus 0 hours per week (At‐Home group; n= 183) from birth to 6 months of age. In‐Care group mothers spent about 12 fewer hours per week interacting with their infants, for about 32% less time; fathers of these infants were more involved in caregiving. The groups did not differ in the quality of mother‐infant interaction. In the In‐Care group, quantity of interaction was related to greater separation anxiety and concerns about effects of maternal employment. Time‐use data were not related to child outcomes at 15 months of age. Results suggest that the effect of extensive time spent apart on the quantity and quality of mother‐infant interaction may be smaller than anticipated.  相似文献   
63.
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments.  相似文献   
64.
The authors examine the effect of premarital cohabitation on the division of household labor in 22 countries. First, women do more routine housework than men in all countries. Second, married couples that cohabited before marriage have a more equal division of housework. Third, national cohabitation rates have equalizing effects on couples regardless of their own cohabitation experience. However, the influence of cohabitation rates is only observed in countries with higher levels of overall gender equality. The authors conclude that the trend toward increasing cohabitation may be part of a broader social trend toward a more egalitarian division of housework.  相似文献   
65.
引入非稳系数和改进系数分析了四种恒流管充电式扫描电路的非线性系数和电源利用系数 ,并提出了改进恒流管充电式扫描电路性能的具体方法 .  相似文献   
66.
Occupational segregation by sex remains the most pervasive aspect of the labour market. In the past, most research on this topic has concentrated on explanations of women’s segregation into low paid and low status occupations, or investigations of women who have crossed gender boundaries into men’s jobs, and the potential impact on them and the occupations. In contrast, this article reports on a small‐scale, qualitative study of ten men who have crossed into what are generally defined as ‘women’s jobs’. In doing so, one of the impacts on them has been that they have experienced challenges to their masculine identity from various sources and in a variety of ways. The men’s reactions to these challenges, and their strategies for developing and accommodating their masculinity in light of these challenges, are illuminating. They either attempted to maintain a traditional masculinity by distancing themselves from female colleagues, and/or partially (re)constructed a different masculinity by identifying with their non‐traditional occupations. This they did as often as they deemed necessary as a response to different forms of challenge to their gender identities from both men and women. Finally, the article argues that these responses work to maintain the men as the dominant gender, even in these traditionally defined ‘women’s jobs’.  相似文献   
67.
Summary.  A fully Bayesian analysis of directed graphs, with particular emphasis on applica- tions in social networks, is explored. The model is capable of incorporating the effects of covariates, within and between block ties and multiple responses. Inference is straightforward by using software that is based on Markov chain Monte Carlo methods. Examples are provided which highlight the variety of data sets that can be entertained and the ease with which they can be analysed.  相似文献   
68.
Gini’s nuclear family   总被引:1,自引:0,他引:1  
The purpose of this paper is to justify the use of the Gini coefficient and two close relatives for summarizing the basic information of inequality in distributions of income. To this end we employ a specific transformation of the Lorenz curve, the scaled conditional mean curve, rather than the Lorenz curve as the basic formal representation of inequality in distributions of income. The scaled conditional mean curve is shown to possess several attractive properties as an alternative interpretation of the information content of the Lorenz curve and furthermore proves to yield essential information on polarization in the population. The paper also provides asymptotic distribution results for the empirical scaled conditional mean curve and the related family of empirical measures of inequality.   相似文献   
69.
Ranked set sampling is a sampling approach that leads to improved statistical inference in situations where the units to be sampled can be ranked relative to each other prior to formal measurement. This ranking may be done either by subjective judgment or according to an auxiliary variable, and it need not be completely accurate. In fact, results in the literature have shown that no matter how poor the quality of the ranking, procedures based on ranked set sampling tend to be at least as efficient as procedures based on simple random sampling. However, efforts to quantify the gains in efficiency for ranked set sampling procedures have been hampered by a shortage of available models for imperfect rankings. In this paper, we introduce a new class of models for imperfect rankings, and we provide a rigorous proof that essentially any reasonable model for imperfect rankings is a limit of models in this class. We then describe a specific, easily applied method for selecting an appropriate imperfect rankings model from the class.  相似文献   
70.
In the paper we present a new method of calculating sampling intervals, so-called windows, allowing an experimenter some flexibility in timing the sample collection, while a minimum required design efficiency for parameter estimation is assured. The method is based on the Equivalence Theorem for D-optimality what makes the length of each window related to the parameter sensitivities. An example of calculating the windows in a pharmacokinetic study is presented. Some other methods of calculating efficient sampling windows are briefly discussed.  相似文献   
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