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91.
This paper examines the place of ethnicity in local authority foster care in the context of the sufficiency duty to secure adequate local placements for looked after children. The analysis draws on two main sources, namely Office for Standards in Education, Children's Services and Skills (OFSTED's) annual survey of fostering agencies and inspection reports for around half the local authority fostering services in England. Sufficiency is gauged in two main ways, comparing numbers of black and minority ethnic (BME) foster carers first with numbers of BME looked after children and second, with local adult (age 25–64) populations. Statistical analysis shows very wide variation on both measures and a significant minority of authorities that perform poorly in terms of the ethnic diversity of their foster carers. Inspection reports also vary widely in the degree and nature of attention given to issues of ethnicity with many offering limited (and sometimes no) challenge to poor performance. These findings are discussed within the broader context of recent trends towards de‐emphasizing the significance of ethnicity in child welfare.  相似文献   
92.
The standard approach to construct nonparametric tolerance intervals is to use the appropriate order statistics, provided a minimum sample size requirement is met. However, it is well-known that this traditional approach is conservative with respect to the nominal level. One way to improve the coverage probabilities is to use interpolation. However, the extension to the case of two-sided tolerance intervals, as well as for the case when the minimum sample size requirement is not met, have not been studied. In this paper, an approach using linear interpolation is proposed for improving coverage probabilities for the two-sided setting. In the case when the minimum sample size requirement is not met, coverage probabilities are shown to improve by using linear extrapolation. A discussion about the effect on coverage probabilities and expected lengths when transforming the data is also presented. The applicability of this approach is demonstrated using three real data sets.  相似文献   
93.
This article explores gendered patterns of online dating and their implications for heterosexual union formation. Using 6 months of online dating data from a midsized Southwestern city (N = 8,259 men, 6,274 women), the authors found that men and women tend to send messages to the most socially desirable alters in the dating market regardless of their own desirability levels. They also found that male initiators connect with more desirable partners than men who wait to be contacted, but female initiators connect with equally desirable partners as women who wait to be contacted. Female‐initiated contacts are also more than twice as likely as male‐initiated contacts to result in a connection, but women send 4 times fewer messages than men. Finally, the authors compared partner desirability levels over repeated exchanges and concluded that couple similarities are more likely to result from relationship termination (i.e., nonreciprocity) than initial homophilous preferences.  相似文献   
94.
This study examines the experiences of children of return migrants to Albania following the economic crisis in Europe. Adopting a longitudinal approach in which participants were followed-up after a year and employing participative qualitative research methods, the study investigates how perceptions of local and translocal spaces and social relations interact to shape children’s (aged 7–12 years) sense of belonging to their parents’ homeland. Findings suggest that the children’s initial positioning is influenced by a perceived lack of everyday places of play and unsettled local interactions with peers. The research indicates further that, over time, children actively seek to inhabit and identify with their new surroundings and that meaning-making is shaped by experiences that transcend multiple localities. It documents how children of return migrants attain a sense of belonging via interacting with different physical and social contexts in a complex process which appears simultaneously facilitated and impeded by adults. Overall, the findings of this research suggest that children’s sense of belonging is negotiated in relation to multiple temporal and spatial frames of reference to which children attribute meaning.  相似文献   
95.
Formaldehyde induced squamous-cell carcinomas in the nasal passages of F344 rats in two inhalation bioassays at exposure levels of 6 ppm and above. Increases in rates of cell proliferation were measured by T. M. Monticello and colleagues at exposure levels of 0.7 ppm and above in the same tissues from which tumors arose. A risk assessment for formaldehyde was conducted at the CIIT Centers for Health Research, in collaboration with investigators from Toxicological Excellence in Risk Assessment (TERA) and the U.S. Environmental Protection Agency (U.S. EPA) in 1999. Two methods for dose-response assessment were used: a full biologically based modeling approach and a statistically oriented analysis by benchmark dose (BMD) method. This article presents the later approach, the purpose of which is to combine BMD and pharmacokinetic modeling to estimate human cancer risks from formaldehyde exposure. BMD analysis was used to identify points of departure (exposure levels) for low-dose extrapolation in rats for both tumor and the cell proliferation endpoints. The benchmark concentrations for induced cell proliferation were lower than for tumors. These concentrations were extrapolated to humans using two mechanistic models. One model used computational fluid dynamics (CFD) alone to determine rates of delivery of inhaled formaldehyde to the nasal lining. The second model combined the CFD method with a pharmacokinetic model to predict tissue dose with formaldehyde-induced DNA-protein cross-links (DPX) as a dose metric. Both extrapolation methods gave similar results, and the predicted cancer risk in humans at low exposure levels was found to be similar to that from a risk assessment conducted by the U.S. EPA in 1991. Use of the mechanistically based extrapolation models lends greater certainty to these risk estimates than previous approaches and also identifies the uncertainty in the measured dose-response relationship for cell proliferation at low exposure levels, the dose-response relationship for DPX in monkeys, and the choice between linear and nonlinear methods of extrapolation as key remaining sources of uncertainty.  相似文献   
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This article considers the quality of pitches in Major League Baseball (MLB). Based on approximately 2.2 million pitches taken from the 2013, 2014, and 2015 MLB seasons, the quality of a particular pitch is evaluated as the expected number of bases conceded. Quality is expressed as a function of various covariates including pitch count, pitch location, pitch type, and pitch speed. The estimation of the pitch quality is obtained through the use of random forest methodology to accommodate the inherent complexity of the relationship between pitch quality and the associated covariates. With the fitted model, various applications are considered which provide new insights on pitching and batting.  相似文献   
99.
This essay explores the uses of the close-up shot in wildlife films and television shows, raising important questions about the scientific truth value of visual narratives that use this camera technique common in fictional films and television. The close-up shot creates a false intimacy between the human audience and the animal subjects, and among the dangerous results of the technique is the impression that animals have human-like thoughts and emotional responses. While this identification of humans with animals might provide the basis for successful political, economic and social action on behalf of animal welfare, use of the technique raises several important ethical questions regarding the representation of nature and science.  相似文献   
100.
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