首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1388篇
  免费   69篇
管理学   171篇
民族学   13篇
人口学   130篇
丛书文集   5篇
理论方法论   211篇
综合类   15篇
社会学   776篇
统计学   136篇
  2023年   13篇
  2022年   6篇
  2021年   11篇
  2020年   35篇
  2019年   57篇
  2018年   56篇
  2017年   66篇
  2016年   71篇
  2015年   42篇
  2014年   59篇
  2013年   247篇
  2012年   59篇
  2011年   53篇
  2010年   40篇
  2009年   38篇
  2008年   37篇
  2007年   52篇
  2006年   48篇
  2005年   30篇
  2004年   33篇
  2003年   31篇
  2002年   46篇
  2001年   27篇
  2000年   18篇
  1999年   27篇
  1998年   15篇
  1997年   9篇
  1996年   20篇
  1995年   15篇
  1994年   11篇
  1993年   11篇
  1992年   14篇
  1991年   14篇
  1990年   18篇
  1989年   7篇
  1988年   13篇
  1987年   8篇
  1985年   11篇
  1984年   8篇
  1983年   5篇
  1982年   10篇
  1981年   4篇
  1980年   8篇
  1979年   6篇
  1977年   3篇
  1975年   11篇
  1974年   4篇
  1971年   5篇
  1970年   3篇
  1969年   3篇
排序方式: 共有1457条查询结果,搜索用时 312 毫秒
91.
Correlated data are commonly analyzed using models constructed using population-averaged generalized estimating equations (GEEs). The specification of a population-averaged GEE model includes selection of a structure describing the correlation of repeated measures. Accurate specification of this structure can improve efficiency, whereas the finite-sample estimation of nuisance correlation parameters can inflate the variances of regression parameter estimates. Therefore, correlation structure selection criteria should penalize, or account for, correlation parameter estimation. In this article, we compare recently proposed penalties in terms of their impacts on correlation structure selection and regression parameter estimation, and give practical considerations for data analysts. Supplementary materials for this article are available online.  相似文献   
92.
It is well known that in finance variances and covariances of asset returns move together over time. Recently, much interest has been aroused by an approach involving the use of the realized covariance (RCOV) matrix constructed from high-frequency returns as the ex-post realization of the covariance matrix of low-frequency returns. For the analysis of dynamics of RCOV matrices, we propose the generalized conditional autoregressive Wishart (GCAW) model. Both the noncentrality matrix and scale matrix of the Wishart distribution are driven by the lagged values of RCOV matrices, and represent two different sources of dynamics, respectively. The GCAW is a generalization of the existing models, and accounts for symmetry and positive definiteness of RCOV matrices without imposing any parametric restriction. Some important properties such as conditional moments, unconditional moments, and stationarity are discussed. Empirical examples including sequences of daily RCOV matrices from the New York Stock Exchange illustrate that our model outperforms the existing models in terms of model fitting and forecasting.  相似文献   
93.
Political tolerance—the willingness to extend civil liberties to traditionally stigmatized groups—is pivotal to the functioning of democracy and the well‐being of members of stigmatized groups. Although political tolerance has traditionally been more common among American elites, we argue that as tolerance has increased, it has also diffused to less educated and less affluent segments of the population. The relative stability of political attitudes over the life course and the socialization of more recent birth cohorts in contexts of increased tolerance suggest that this diffusion of tolerance occurs across birth cohorts rather than time periods. Using age‐period‐cohort models and more than three and a half decades of repeated cross‐sectional survey data, we find persistent and robust across‐cohort declines in the importance of both income and higher education in determining levels of political tolerance. Declines in the effects of socioeconomic status are evident with tolerance toward all five out‐groups in the analysis—anti‐religionists, gays and lesbians, communists, militarists, and racists—but to varying degrees. These findings fit with a model of changes in public opinion, particularly views of civil and political rights, through processes of cultural diffusion and cohort replacement.  相似文献   
94.
Parent involvement in the process of creating an Individualized Education Plan (IEP) is authorized under the Individuals with Disabilities Education Act, a federal law in the United States that ensures children with disabilities have the opportunity to receive a free appropriate public education alongside their peers without disabilities in the least restrictive environment. Yet much research has shown that parents often feel like outsiders during the process. To understand parent perspectives about how educators might help make the IEP process more collaborative and inclusive, this study collected qualitative data from 35 parents of students with disabilities who have worked to develop an IEP with a school team. Our findings provide insight into parent experiences and evidence that parents have many suggestions for how educators can improve the IEP process. In our discussion section, we provide educators with strategies to address parent suggestions.  相似文献   
95.
This field study provides variables that can be used by practitioners as action levers and by future researchers as the basis for theoretical development. Conclusions from relevant literature and findings from interviews with interdisciplinary research management identified forty variables that were viewed as important to interdisciplinary research project success. After adjusting the data for reliability attenuation, these variables were further analyzed to identify the best prediction equation. The findings suggested that project age or the longevity of the project and open discussion of disagreements were the best predictors of performance.  相似文献   
96.
97.
Few programs to enhance fathers' engagement with children have been systematically evaluated, especially for low‐income minority populations. In this study, 289 couples from primarily low‐income Mexican American and European American families were randomly assigned to one of three conditions and followed for 18 months: 16‐week groups for fathers, 16‐week groups for couples, or a 1‐time informational meeting. Compared with families in the low‐dose comparison condition, intervention families showed positive effects on fathers' engagement with their children, couple relationship quality, and children's problem behaviors. Participants in couples' groups showed more consistent, longer term positive effects than those in fathers‐only groups. Intervention effects were similar across family structures, income levels, and ethnicities. Implications of the results for current family policy debates are discussed.  相似文献   
98.
Based on a two-year self-study by a group of early-career scholars of color, we explore and purposefully name our role, within the contemporary context of neoliberal reform, as educational researchers of color who are former K-12 teachers. We capture the insights that emerged from our self-study through a close reading of dominant neoliberal educational reform discourses, particularly through an examination of the writings of Michelle Rhee and Wendy Kopp. Along three dimensions of: (1) experience as teachers; (2) solidarity with teachers; and (3) analyses of racism in schooling, we characterize prominent discourses through which educators, researchers, and the public describe teachers and teaching. We name these discursive frames to make explicit the assumptions that are embedded in each and the intentional or inadvertent consequences of each. Finally, we propose a teacher solidarity lens through which we strive to approach our research and work with teachers.  相似文献   
99.
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号