全文获取类型
收费全文 | 5271篇 |
免费 | 843篇 |
专业分类
管理学 | 1109篇 |
民族学 | 22篇 |
人才学 | 1篇 |
人口学 | 277篇 |
丛书文集 | 5篇 |
理论方法论 | 891篇 |
综合类 | 43篇 |
社会学 | 3079篇 |
统计学 | 687篇 |
出版年
2023年 | 26篇 |
2022年 | 12篇 |
2021年 | 95篇 |
2020年 | 182篇 |
2019年 | 387篇 |
2018年 | 188篇 |
2017年 | 302篇 |
2016年 | 357篇 |
2015年 | 328篇 |
2014年 | 307篇 |
2013年 | 698篇 |
2012年 | 309篇 |
2011年 | 289篇 |
2010年 | 246篇 |
2009年 | 207篇 |
2008年 | 246篇 |
2007年 | 217篇 |
2006年 | 214篇 |
2005年 | 173篇 |
2004年 | 181篇 |
2003年 | 155篇 |
2002年 | 116篇 |
2001年 | 124篇 |
2000年 | 112篇 |
1999年 | 67篇 |
1998年 | 42篇 |
1997年 | 26篇 |
1996年 | 40篇 |
1995年 | 27篇 |
1994年 | 39篇 |
1993年 | 26篇 |
1992年 | 31篇 |
1991年 | 31篇 |
1990年 | 24篇 |
1989年 | 30篇 |
1988年 | 26篇 |
1987年 | 17篇 |
1986年 | 20篇 |
1985年 | 14篇 |
1984年 | 17篇 |
1983年 | 16篇 |
1982年 | 16篇 |
1981年 | 13篇 |
1980年 | 17篇 |
1979年 | 21篇 |
1978年 | 16篇 |
1976年 | 9篇 |
1975年 | 7篇 |
1974年 | 8篇 |
1971年 | 5篇 |
排序方式: 共有6114条查询结果,搜索用时 834 毫秒
141.
Martin Huber 《Econometric Reviews》2014,33(8):869-905
Sample selection and attrition are inherent in a range of treatment evaluation problems such as the estimation of the returns to schooling or training. Conventional estimators tackling selection bias typically rely on restrictive functional form assumptions that are unlikely to hold in reality. This paper shows identification of average and quantile treatment effects in the presence of the double selection problem into (i) a selective subpopulation (e.g., working—selection on unobservables) and (ii) a binary treatment (e.g., training—selection on observables) based on weighting observations by the inverse of a nested propensity score that characterizes either selection probability. Weighting estimators based on parametric propensity score models are applied to female labor market data to estimate the returns to education. 相似文献
142.
Although cohabitation and childbearing within cohabitation have increased in Europe over recent decades, the variation across Europe remains remarkably wide. Most studies on union formation have not explicitly addressed the role of state policies in the development of cohabitation or discussed how countries have responded to changes in union formation by passing legislation. Here we discuss historical and theoretical issues relevant to the relationship between state policies and union formation and describe policies relating to cohabitation and marriage in nine Western European countries. Drawing on secondary sources and legal documents, we examine the quantity of regulations that mention cohabitation and the approach to cohabitation in 19 policy dimensions. We then place the countries along a continuum, from those that have equalized cohabitation and marriage to those that only regulate marriage. As a whole, this overview raises questions about the changing institution of marriage, as well as the increasing institutionalization of cohabitation. 相似文献
143.
Who owns the trauma? A Kleinian perspective on the dialogue between child protection social workers and the media
下载免费PDF全文
![点击此处可从《Child & Family Social Work》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The present paper makes use of the developmental model of movement between mental positions that was formulated by psychoanalyst Melanie Klein, aimed at understanding the dialogue that takes place between the media and social workers in the field of child welfare, centring around incidents of murder within the family. The basic concept in the paper is that when working with children who are victims of abuse and with their parents, and when reporting on them as well, the feeling of personal control is severely undermined, being associated with the loss of the hallowed social value known as ‘unconditional love of a parent for his child’. The paper illustrates these theoretical ideas by describing two cases that took place in Israel and recommendations are made regarding ways of promoting the dialogue between the professions. 相似文献
144.
Data sets with excess zeroes are frequently analyzed in many disciplines. A common framework used to analyze such data is the zero-inflated (ZI) regression model. It mixes a degenerate distribution with point mass at zero with a non-degenerate distribution. The estimates from ZI models quantify the effects of covariates on the means of latent random variables, which are often not the quantities of primary interest. Recently, marginal zero-inflated Poisson (MZIP; Long et al. [A marginalized zero-inflated Poisson regression model with overall exposure effects. Stat. Med. 33 (2014), pp. 5151–5165]) and negative binomial (MZINB; Preisser et al., 2016) models have been introduced that model the mean response directly. These models yield covariate effects that have simple interpretations that are, for many applications, more appealing than those available from ZI regression. This paper outlines a general framework for marginal zero-inflated models where the latent distribution is a member of the exponential dispersion family, focusing on common distributions for count data. In particular, our discussion includes the marginal zero-inflated binomial (MZIB) model, which has not been discussed previously. The details of maximum likelihood estimation via the EM algorithm are presented and the properties of the estimators as well as Wald and likelihood ratio-based inference are examined via simulation. Two examples presented illustrate the advantages of MZIP, MZINB, and MZIB models for practical data analysis. 相似文献
145.
We examined the moderating roles of individualistic and collectivistic cultural orientations and academic achievement on the relation between Chinese adolescents’ shyness and depressive symptoms. A sample of Chinese adolescents (N = 492) from an urban school participated in the study during seventh (T1) and eighth (T2) grades. Adolescents self‐reported their shyness, cultural orientations, and depressive symptoms. The school provided records of their academic achievement. Concurrently, shyness and individualism were positively whereas collectivism and academic achievement were negatively, associated with adolescents’ depressive symptoms. Longitudinally, T1 shyness (but not individualism, collectivism, or academic achievement) predicted T2 depressive symptoms after controlling for stability in depressive symptoms. Concurrent relations between shyness and depressive symptoms were moderated by adolescents’ cultural orientations. Specifically, collectivism was protective whereas individualism was harmful, for shy adolescents’ adjustment. Furthermore, collectivism and academic achievement jointly moderated the relations between shyness and depressive symptoms concurrently and longitudinally. The results suggest that cultural orientations may influence shy adolescents’ depression symptoms through individual‐level self‐evaluation, and indicate that cultural factors and academic achievement need to be considered comprehensively for understanding and improving shy Chinese adolescents’ psychological adjustment. 相似文献
146.
ABSTRACTThe concept of a movement landscape is used to analyse continuities and changes in popular mobilization since the end of formal apartheid. Focusing on four different episodes of protest since 1997, the article examines their relationship to the ANC movement and traditions, and their organizational forms. It finds a general theme of fluid and ephemeral organization, and a distrust of formal hierarchal organization, that is relatively new in South Africa. The Marikana strikes produced the most far-reaching organizational realignments, while the student struggles generated the most innovative re-imaginings of political forms and discourses. It concludes that although there have been critiques of and challenges to the ANC tradition, and experiments with new forms of organizing, they have not produced alternatives that have lasted or dislodged the dominant approaches defined and popularized by the ANC movement. 相似文献
147.
Development of predictive signatures for treatment selection in precision medicine with survival outcomes
下载免费PDF全文
![点击此处可从《Pharmaceutical statistics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
For survival endpoints in subgroup selection, a score conversion model is often used to convert the set of biomarkers for each patient into a univariate score and using the median of the univariate scores to divide the patients into biomarker‐positive and biomarker‐negative subgroups. However, this may lead to bias in patient subgroup identification regarding the 2 issues: (1) treatment is equally effective for all patients and/or there is no subgroup difference; (2) the median value of the univariate scores as a cutoff may be inappropriate if the sizes of the 2 subgroups are differ substantially. We utilize a univariate composite score method to convert the set of patient's candidate biomarkers to a univariate response score. We propose applying the likelihood ratio test (LRT) to assess homogeneity of the sampled patients to address the first issue. In the context of identification of the subgroup of responders in adaptive design to demonstrate improvement of treatment efficacy (adaptive power), we suggest that subgroup selection is carried out if the LRT is significant. For the second issue, we utilize a likelihood‐based change‐point algorithm to find an optimal cutoff. Our simulation study shows that type I error generally is controlled, while the overall adaptive power to detect treatment effects sacrifices approximately 4.5% for the simulation designs considered by performing the LRT; furthermore, the change‐point algorithm outperforms the median cutoff considerably when the subgroup sizes differ substantially. 相似文献
148.
Brittany N. Fox‐Williams 《Sociological Forum》2019,34(1):115-137
Prior work on youth–police relations examines young people's general perceptions of the police, their differential treatment by police officers, and officers' discretion in dealing with youth. Yet researchers have largely neglected the question of how young people attempt to shape these encounters. I address this critical gap, while also incorporating the experiences of “on track” youth and young women—two groups that are not exempt from police contact but traditionally ignored in the youth–police literature. Drawing on semistructured group and individual interviews with 19 black young people in New York City, I investigate the strategies they employ or subscribe to in navigating police contact. Three types of strategies emerged from my analysis: avoidance, management, and symbolic resistance. Avoidance strategies are marked by young people's attempts to preemptively steer clear of officers on the street. Management strategies are employed by young people during police encounters to limit risk or harm, while symbolic resistance is a subtle tactic used by some youth to preserve their dignity in these interactions. This study also considers the gender differences in respondents' approaches and offers new insights into how they assess their police interactions in an era of highly publicized incidents of police brutality. 相似文献
149.
Bidding above the risk‐neutral Nash equilibrium in first price sealed bid auctions has traditionally been ascribed to risk aversion. Later studies, however, offer other explanations and even argue that risk aversion plays no or a minor role. In a novel experimental design, we directly test the relationship between risk aversion and overbidding by systematically varying the distribution of risk attitudes in auction markets. We find a significant relationship between our measure of risk aversion and overbidding. (JEL D44, C91) 相似文献
150.
Graduation model interventions represent a new wave of anti‐poverty programming that seeks to offer a sustainable pathway out of poverty. An expanding evidence base points towards positive economic outcomes at household level but little is known about impacts on child well‐being. This paper investigates children’s well‐being in Burundi during and after participation in a graduation model programme using a longitudinal mixed‐methods approach. The programme is found to improve child well‐being, particularly in relation to housing, food security and education. Covariate shocks undermine sustainability of effects but greater knowledge, experience and prioritisation of children’s needs contribute to harnessing improved outcomes. 相似文献