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991.
In many economic models, theory restricts the shape of functions, such as monotonicity or curvature conditions. This article reviews and presents a framework for constrained estimation and inference to test for shape conditions in parametric models. We show that “regional” shape-restricting estimators have important advantages in terms of model fit and flexibility (as opposed to standard “local” or “global” shape-restricting estimators). In our empirical illustration, this is the first article to impose and test for all shape restrictions required by economic theory simultaneously in the “Berndt and Wood” data. We find that this dataset is consistent with “duality theory,” whereas previous studies have found violations of economic theory. We discuss policy consequences for key parameters, such as whether energy and capital are complements or substitutes.  相似文献   
992.
The autoregressive Cauchy estimator uses the sign of the first lag as instrumental variable (IV); under independent and identically distributed (i.i.d.) errors, the resulting IV t-type statistic is known to have a standard normal limiting distribution in the unit root case. With unconditional heteroskedasticity, the ordinary least squares (OLS) t statistic is affected in the unit root case; but the paper shows that, by using some nonlinear transformation behaving asymptotically like the sign as instrument, limiting normality of the IV t-type statistic is maintained when the series to be tested has no deterministic trends. Neither estimation of the so-called variance profile nor bootstrap procedures are required to this end. The Cauchy unit root test has power in the same 1/T neighborhoods as the usual unit root tests, also for a wide range of magnitudes for the initial value. It is furthermore shown to be competitive with other, bootstrap-based, robust tests. When the series exhibit a linear trend, however, the null distribution of the Cauchy test for a unit root becomes nonstandard, reminiscent of the Dickey-Fuller distribution. In this case, inference robust to nonstationary volatility is obtained via the wild bootstrap.  相似文献   
993.
In this paper, we focus on the problem of factor screening in nonregular two-level designs through gradually reducing the number of possible sets of active factors. We are particularly concerned with situations when three or four factors are active. Our proposed method works through examining fits of projection models, where variable selection techniques are used to reduce the number of terms. To examine the reliability of the methods in combination with such techniques, a panel of models consisting of three or four active factors with data generated from the 12-run and the 20-run Plackett–Burman (PB) design is used. The dependence of the procedure on the amount of noise, the number of active factors and the number of experimental factors is also investigated. For designs with few runs such as the 12-run PB design, variable selection should be done with care and default procedures in computer software may not be reliable to which we suggest improvements. A real example is included to show how we propose factor screening can be done in practice.  相似文献   
994.
With competing risks data, one often needs to assess the treatment and covariate effects on the cumulative incidence function. Fine and Gray proposed a proportional hazards regression model for the subdistribution of a competing risk with the assumption that the censoring distribution and the covariates are independent. Covariate‐dependent censoring sometimes occurs in medical studies. In this paper, we study the proportional hazards regression model for the subdistribution of a competing risk with proper adjustments for covariate‐dependent censoring. We consider a covariate‐adjusted weight function by fitting the Cox model for the censoring distribution and using the predictive probability for each individual. Our simulation study shows that the covariate‐adjusted weight estimator is basically unbiased when the censoring time depends on the covariates, and the covariate‐adjusted weight approach works well for the variance estimator as well. We illustrate our methods with bone marrow transplant data from the Center for International Blood and Marrow Transplant Research. Here, cancer relapse and death in complete remission are two competing risks.  相似文献   
995.
行政法原则在行政执法实践和司法审判实践中具有重要意义,而行政判例中则蕴含着丰富的行政法原则.以梁宝富案关于合法性审查和保护诉权及赖恒安案关于成熟原则的行政判例为例来看,通过行政判例来运用、发展、创制行政法原则,对于推进我国行政法治有着极其重要的意义.  相似文献   
996.
高等学校自主权是一个极其复杂的概念,源于西方大学的自治权,就性质而言,有时表现为权力,有时又表现为权利;就内容而言,有的表现为权力,有的表现为权威.在我国的权力语境中,高校自主权就是指高等学校依据法律、法规的规定,以办学目标为基础,以学术自由为主要内容,按照自身特点和内部规律的要求,由其章程所规定、效力只及于内部成员的自主决策、自主实施、自主承担责任的资格和能力.  相似文献   
997.
In Britain in recent years social mobility has become a topic of central political concern, primarily as a result of the effort made by New Labour to make equality of opportunity rather than equality of condition a focus of policy. Questions of the level, pattern and trend of mobility thus bear directly on the relevance of New Labour's policy analysis, and in turn are likely be crucial to the evaluation of its performance in government. However, politically motivated discussion of social mobility often reveals an inadequate grasp of both empirical and analytical issues. We provide new evidence relevant to the assessment of social mobility - in particular, intergenerational class mobility - in contemporary Britain through cross-cohort analyses based on the NCDS and BCS datasets which we can relate to earlier cross-sectional analyses based on the GHS. We find that, contrary to what seems now widely supposed, there is no evidence that absolute mobility rates are falling; but, for men, the balance of upward and downward movement is becoming less favourable. This is overwhelmingly the result of class structural change. Relative mobility rates, for both men and women, remain essentially constant, although there are possible indications of a declining propensity for long-range mobility. We conclude that under present day structural conditions there can be no return to the generally rising rates of upward mobility that characterized the middle decades of the twentieth century - unless this is achieved through changing relative rates in the direction of greater equality or, that is, of greater fluidity. But this would then produce rising rates of downward mobility to exactly the same extent - an outcome apparently unappreciated by, and unlikely to be congenial to, politicians preoccupied with winning the electoral 'middle ground'.  相似文献   
998.
To incorporate newcomers into membership, a group employs socialization strategies to transform the characteristics of the newcomers, so that it can admit them with the confidence that their behaviour will not endanger group unity. Analyses of socialization emphasize that novices' interiorization of an institutional definition of group behaviour is a necessary condition to ensure successful socialization. The contemporary Religious Society of Friends in Britain, however, is a non-doctrinal religious movement that avoids defining the content of its beliefs and practices. To analyse the socializing interaction between members and newcomers in this movement in Britain, and among co-religionists in the USA, this inquiry applies a model of socialization that does not include assumptions about the role played by cognition in socialization (Long and Hadden 1983). My results show that: (a) the diffuseness in Friends' collective explanations of institutional conduct supports novices' identification with institutional practice, and (b) experimental and affective components in socialization motivate novices to imitate institutional behaviour despite the fact that Friends have no authoritative explanations of such behaviour. The data suggest that socialization and social cohesion are not necessarily as strongly cognitive-oriented phenomena as they were previously thought to be. This finding has important implications for thinking about social cohesion in postmodern society.  相似文献   
999.
A comprehensive framework for guiding analyses of internal migration is lacking. This study contributes to the family migration literature in three important ways. We develop a multilevel theoretical framework emphasizing an integration of individual-, family-, and neighborhood-level effects; introduce multilevel statistical modeling; and explicitly assess how effects of economic-based explanatory variables vary by gender. Our data are from the Panel Study of Income Dynamics (PSID). We find that the likelihood of a family migrating is affected by economic and non-economic factors, some of which vary by gender. We add to the dual-earner migration literature by finding that wives are not likely to be tied-movers, but husbands are likely to be tied-stayers. Neighborhood factors also are important to the decision to migrate.
Steven Garasky (Corresponding author)Email:
  相似文献   
1000.
This paper investigates how policy and values interrelate concerning expectations of childcare based on 80 interviews with 40 families with young children from France and Sweden, respectively. Upbringing, learning and socialization are important expectations among French parents. The results presented here are in line with educational goals that may have been influenced by policy. The findings suggest that France may, in terms of expectations on childcare, still belong to the conservative cluster as categorized by Esping-Andersen (1990 Esping-Andersen, G. 1990. The three worlds of welfare capitalism, Cambridge: Polity Press.  [Google Scholar]), although family policy may differ from that of, for example, Germany and Italy in the same cluster. Swedish parents stress the importance of the individual child as well as pedagogy, thus, indicating compatibility between a parental wish for the individual development of the child and an emphasis on collective care in Swedish family policy.  相似文献   
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