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21.
This article describes a method for reclassifying causes of death in the Netherlands for the period 1875–1992. Two criteria should be met to obtain a useful classification to study the epidemiological transition. First, the categories should be nosologically continuous over the period under study and second, there should be enough detail in causes which are important in the context of the epidemiological transition viz. communicable diseases, non-communicable diseases and external causes of death. A method developed by Vallin and Meslé (1988), which involves ‘dual correspondence tables’ and ‘fundamental associations’, was used to create nosologically continuous categories. These categories were tested for statistical continuity during the transition years of one ICD-revision to the next, using ordinary least squares regression analysis. The reclassification procedure resulted in a nested classification consisting of three levels of refinement of causes of death: 27 causes, 1875–1992; 65 causes, 1901–1992; and 92 causes, 1931–1992. On the basis of this classification, 43% of all deaths in 1875–79 and 98% of all deaths in 1992 could be allocated to either communicable diseases, non-communicable diseases or external causes.  相似文献   
22.
We provide a possible explanation for the empirical puzzle that mergers often reduce profits, but raise share prices. If being an “insider” is better than being an “outsider”, firms may merge to preempt their partner merging with a rival. The insiders' stock market value is increased, since the risk of becoming an outsider is eliminated. These results are derived in an endogenous‐merger model, predicting the conditions under which mergers occur, when they occur, and how the surplus is shared. (JEL: L13, L41, G34, C78)  相似文献   
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We construct a model where incumbents can either acquire basic innovations from entrepreneurs, or wait and acquire developed innovations from entrepreneurial firms supported by venture capitalists. We show that venture‐backed entrepreneurial firms have an incentive to overinvest in development vis à vis incumbents due to strategic product market effects on the sales price of a developed innovation. This will trigger preemptive acquisitions by incumbents, thus increasing the reward for entrepreneurial innovations. We also show that venture capital can emerge in equilibrium if venture capitalists have cost advantages, or if development is associated with double moral hazard problems. (JEL: G24, L1, L2, M13, O3)  相似文献   
25.
Lundberg O, Fritzell J, Åberg Yngwe M, Kölegård ML. The potential power of social policy programmes: income redistribution, economic resources and health Int J Soc Welfare 2010: ??: ??–??© 2010 The Author(s), Journal compilation © 2010 Blackwell Publishing Ltd and International Journal of Social Welfare. This Supplement includes a number of articles dealing with the role of social policy schemes for public health across the life course. As a key social determinant of health, poverty and its consequences have historically been at the forefront of the public health discussion. But also in rich countries today, economic resources are likely to be important for health and survival, both on an individual and an aggregate level. This introductory article serves as a background for the more specific analyses that follow. The focus is on why income and income inequality could have an effect on individual and population health. We discuss relationships between the individual and population levels and between income and health, and some of the possible mechanisms involved. We also present arguments for why welfare state institutions may matter.  相似文献   
26.
Foster children often have behavioural problems. Behavioural problems influence the level of parenting stress and can lead to a breakdown. In this study, parenting behaviour of foster mothers is mapped, and the influence of behavioural problems and parenting stress on the parenting behaviour 2 years later is examined. Data of behavioural problems, family stress and parenting were gathered from 49 foster mothers. Problem behaviour has a direct negative impact on parenting and leads to less support and more negative control. It also results in more parenting stress. Foster parents need to be trained aiming at preventing ineffective parenting. The well‐being of foster parents needs to be guarded. Higher levels of parenting stress lead to less effective parenting.  相似文献   
27.
Family foster care is the option of choice for children in need of out‐of‐home care in Flanders and the Netherlands. Foster care is however a vulnerable intervention, and questions can be raised as to its efficacy. Although the literature on placement breakdown has made significant progress during the last years, empirical knowledge regarding breakdown in Flanders and the Netherlands remains scant. Consequently, this study aimed at investigating prevalence and precursors of breakdowns in long‐term foster care, the duration of placement before breakdown, and the association of child and placement characteristics with breakdown. Case files of 271 Dutch and 309 Flemish foster children were analysed with a coding scheme designed for this study. After 6 years, 398 placements had terminated: 169 placements broke down and 229 placements ended positively. Placements broke down mainly because of behavioural problems of the foster child, foster parents' parenting problems, and conflicts between birth and foster parents. Foster children with behavioural problems, older foster children, foster children denied treatment, and foster children in care because of sexual abuse were more at risk of breakdown. Assessing these factors is important when evaluating the appropriateness of a family foster care placement.  相似文献   
28.
Missing data methods, maximum likelihood estimation (MLE) and multiple imputation (MI), for longitudinal questionnaire data were investigated via simulation. Predictive mean matching (PMM) was applied at both item and scale levels, logistic regression at item level and multivariate normal imputation at scale level. We investigated a hybrid approach which is combination of MLE and MI, i.e. scales from the imputed data are eliminated if all underlying items were originally missing. Bias and mean square error (MSE) for parameter estimates were examined. ML seemed to provide occasionally the best results in terms of bias, but hardly ever on MSE. All imputation methods at the scale level and logistic regression at item level hardly ever showed the best performance. The hybrid approach is similar or better than its original MI. The PMM-hybrid approach at item level demonstrated the best MSE for most settings and in some cases also the smallest bias.  相似文献   
29.
Conditional cash transfers (CCTs) are often being promoted for their simultaneous advantages of short‐term income protection and long‐term human capital investments. Yet, existing evaluations have largely failed to test the underlying programme theory, and few empirical case studies have explored inherent contradictions and ambiguous consequences of this hybrid approach. To further understand the programmes' social policy implications, this study identifies and analyzes such ambiguities and paradoxical consequences in the case of Uruguay's CCT‐programme, Asignaciones Familiares (AFAM). Drawing on qualitative data from interviews with beneficiaries and members of the commission who designed the programme, this study reveals major paradoxes in AFAM's design and implementation caused by various endogenous factors. Relevant to social policy in general, and CCT‐evaluations in particular, findings also indicate that the hybrid social assistance approach may have perverse effects on the programme's twin objectives.  相似文献   
30.
Extreme-value copulas arise in the asymptotic theory for componentwise maxima of independent random samples. An extreme-value copula is determined by its Pickands dependence function, which is a function on the unit simplex subject to certain shape constraints that arise from an integral transform of an underlying measure called spectral measure. Multivariate extensions are provided of certain rank-based nonparametric estimators of the Pickands dependence function. The shape constraint that the estimator should itself be a Pickands dependence function is enforced by replacing an initial estimator by its best least-squares approximation in the set of Pickands dependence functions having a discrete spectral measure supported on a sufficiently fine grid. Weak convergence of the standardized estimators is demonstrated and the finite-sample performance of the estimators is investigated by means of a simulation experiment.  相似文献   
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