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261.
262.
Mothers of Japanese or South American ancestry living in the United States participated. Similarities and differences in mothers' social and didactic parenting behaviors and beliefs, and direct relations between behaviors and beliefs in these 2 domains of interaction, are reported. In accordance with a common collectivist orientation, Japanese American and South American mothers reported that they engaged in more social than didactic interactions with their infants, and South American mothers more than Japanese American mothers. However, in actuality, both of these acculturating groups engaged in more didactic than social behaviors with their infants and did so for longer periods of time. Not surprisingly, no belief‐behavior relations emerged in either group.  相似文献   
263.
We present several approaches to modeling latent structure in longitudinal studies when the covariance itself is the primary focus of the analysis. This is a departure from much of the work on longitudinal data analysis, in which attention is focused solely on the cross-sectional mean and the influence of covariates on the mean. Such analyses are particularly important in policy-related studies, in which the heterogeneity of the population is of interest. We describe several traditional approaches to this modeling and introduce a flexible, parsimonious class of covariance models appropriate to such analyses. This class, while rooted in the tradition of mixed effects and random coefficient models, merges several disparate modeling philosophies into what we view as a hybrid approach to longitudinal data modeling. We discuss the implications of this approach and its alternatives especially on model interpretation. We compare several implementations of this class to more commonly employed mixed effects models to describe the strengths and limitations of each. These alternatives are compared in an application to long-term trends in wage inequality for young workers. The findings provide additional guidance for the model formulation process in both statistical and substantive senses.  相似文献   
264.
Prospect theory for continuous distributions   总被引:2,自引:0,他引:2  
We extend the original form of prospect theory by Kahneman and Tversky from finite lotteries to arbitrary probability distributions, using an approximation method based on weak-⋆ convergence. The resulting formula is computationally easier than the corresponding formula for cumulative prospect theory and makes it possible to use prospect theory in future applications in economics and finance. Moreover, we suggest a method how to incorporate a crucial step of the “editing phase” into prospect theory and to remove in this way the discontinuity of the original model.
Mei Wang (Corresponding author)Email:
  相似文献   
265.
In recent years, the attention of French public opinion has been focused on the noxious effects of new ways of organizing work. Stress, “suffering”, burnout, psychosocial risks and suicides are topics that have brought experts, the media and politicians into action. What do the social sciences have to say about this? Among the several reactions presented, the principal contrast arises between those who analyze the ills of work as “social constructions” and those who see them as the implications of a trend toward intensifying job-related activities.  相似文献   
266.
The focus of this installment of “The Balance Point” is “shelf-ready” print serials acquisitions, including functions associated with traditional consolidation services (ordering, receiving, check-in, labeling, claiming and batch shipments), and the newer capabilities of uploading check-in data automatically into library systems. Featured authors discuss traditional vendor consolidation services, pilot projects and experiments in the pursuit of what they define as genuinely “shelf-ready” periodicals. The authors view obtaining “shelf-ready” print journal issues as an effective and efficient means of managing print serials operations while coping with the demands of managing digital resource acquisitions with limited financial resources.  相似文献   
267.
Understanding healthcare viral disease transmission and the effect of infection control interventions will inform current and future infection control protocols. In this study, a model was developed to predict virus concentration on nurses’ hands using data from a bacteriophage tracer study conducted in Tucson, Arizona, in an urgent care facility. Surfaces were swabbed 2 hours, 3.5 hours, and 6 hours postseeding to measure virus spread over time. To estimate the full viral load that would have been present on hands without sampling, virus concentrations were summed across time points for 3.5‐ and 6‐hour measurements. A stochastic discrete event model was developed to predict virus concentrations on nurses’ hands, given a distribution of virus concentrations on surfaces and expected frequencies of hand‐to‐surface and orifice contacts and handwashing. Box plots and statistical hypothesis testing were used to compare the model‐predicted and experimentally measured virus concentrations on nurses’ hands. The model was validated with the experimental bacteriophage tracer data because the distribution for model‐predicted virus concentrations on hands captured all observed value ranges, and interquartile ranges for model and experimental values overlapped for all comparison time points. Wilcoxon rank sum tests showed no significant differences in distributions of model‐predicted and experimentally measured virus concentrations on hands. However, limitations in the tracer study indicate that more data are needed to instill more confidence in this validation. Next model development steps include addressing viral concentrations that would be found naturally in healthcare environments and measuring the risk reductions predicted for various infection control interventions.  相似文献   
268.
Caregiver education is known to relate to the growth of children, but possible mediation mechanisms of this association are poorly characterized and generally lack empirical support. We test whether instructional capital (caregiver education) leads to improved infant growth through availability of physical capital (household resources) across a wide swath of low‐ and middle‐income countries (LMIC). Using the Multiple Indicator Cluster Survey, we explore relations among caregiver education, household resources, and infant (M age = 0.99 years) growth in 117,881 families living in 39 LMIC. Overall, household resources mediated 76% of the small association between caregiver education and infant growth. When disaggregated by countries characterized by low, medium, and high levels of human development (as indexed by average life expectancy, education, and gross domestic product), household resources mediated 48–78% of the association between caregiver education and infant growth. Caregiver education had effects on infant growth through household resources in countries characterized by low, medium, and high levels of human development; for girls and boys; and controlling for indexes of infant feeding and health.  相似文献   
269.
We analyze whether the use of CoCo bonds as a financing instrument improves credit supply and therefore reduces the likelihood of a credit crunch. In our simple model, banks decide about granting an additional loan. In case of the bank violating the regulatory constraint, it needs to issue equity associated with adjustment costs. The contribution of the paper is threefold: First, this simple model explains credit crunches in the sense that the loan decision does not only depend on loan characteristics but also on the bank’s prospects. Second, CoCo bonds can always be designed such that all loans with non-negative net present value are granted, which prevents the danger of a credit crunch. Third, banks might not want to issue CoCo bonds even though these instruments help to improve credit supply. This problem primarily concerns banks with favorable prospects, thereby challenging the notion that CoCo bonds should be issued in good times as a protection during bad times.  相似文献   
270.
"We present a simulation model that synthesizes Malthusian and Boserupian notions of the way population growth and economic development were intertwined. The non-linear stochastic model consists of a system of equations whose dynamics culminate in an industrial revolution after hundreds of iterations. The Industrial Revolution [in Europe] can thus be conceptualized as a permanent 'escape' from the Malthusian trap that occurs once the economy is capable of permanently sustaining an ever growing population. We investigate the conditions for such an escape and their sensitivity to the parameters of the model....Our results show that the likelihood of an escape is sensitive to the savings rate and to the output elasticities of the two sectors of the economy. When not in a subsistence crisis, the chances that an escape will occur increase for larger values of the ratio of the savings rate to the growth rate of the population. The chances of an escape also increase substantially for larger values of the output elasticities of labor." (SUMMARY IN FRE)  相似文献   
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