全文获取类型
收费全文 | 11170篇 |
免费 | 280篇 |
专业分类
管理学 | 1614篇 |
民族学 | 51篇 |
人才学 | 1篇 |
人口学 | 1173篇 |
丛书文集 | 60篇 |
教育普及 | 1篇 |
理论方法论 | 958篇 |
现状及发展 | 1篇 |
综合类 | 134篇 |
社会学 | 5286篇 |
统计学 | 2171篇 |
出版年
2023年 | 76篇 |
2022年 | 59篇 |
2020年 | 163篇 |
2019年 | 220篇 |
2018年 | 261篇 |
2017年 | 354篇 |
2016年 | 283篇 |
2015年 | 180篇 |
2014年 | 239篇 |
2013年 | 1929篇 |
2012年 | 380篇 |
2011年 | 311篇 |
2010年 | 257篇 |
2009年 | 245篇 |
2008年 | 274篇 |
2007年 | 270篇 |
2006年 | 243篇 |
2005年 | 254篇 |
2004年 | 242篇 |
2003年 | 214篇 |
2002年 | 243篇 |
2001年 | 281篇 |
2000年 | 284篇 |
1999年 | 269篇 |
1998年 | 180篇 |
1997年 | 170篇 |
1996年 | 164篇 |
1995年 | 163篇 |
1994年 | 132篇 |
1993年 | 150篇 |
1992年 | 167篇 |
1991年 | 145篇 |
1990年 | 157篇 |
1989年 | 181篇 |
1988年 | 151篇 |
1987年 | 136篇 |
1986年 | 148篇 |
1985年 | 167篇 |
1984年 | 165篇 |
1983年 | 156篇 |
1982年 | 121篇 |
1981年 | 105篇 |
1980年 | 102篇 |
1979年 | 137篇 |
1978年 | 88篇 |
1977年 | 87篇 |
1976年 | 87篇 |
1975年 | 80篇 |
1974年 | 80篇 |
1973年 | 73篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
361.
Urban Ecosystems - Although amphibians use human-created habitats in urban landscapes, few studies have investigated the quality of these habitats. To assess habitat quality of stormwater... 相似文献
362.
Brandy M. Jenner Kit C. Myers 《International Journal of Social Research Methodology》2019,22(2):165-177
While qualitative researchers increasingly accept online video interviews as a reliable method, many maintain concerns about rapport and data quality. Drawing on two separate interview projects conducted in private in-person settings, public in-person settings, and privately via Skype, we compare interview contexts with regard to rapport, suitability to sensitive topics, interview duration, and scheduling concerns raised by prior research. Analytical comparison of these two corpuses of data suggest, largely in contrast to previous literature, that (1) interviews conducted in private settings (either in-person or via Skype) result in more sharing of deeply personal experiences, and there is little difference in this exceptional disclosure between Skype and in-person private interviews; (2) interviewing via Skype produces neither reduction nor inappropriate excesses of rapport; and (3) Skype interviews are a popular choice among participants, did not result in shorter interview duration, and were not subject to greater rescheduling or cancellation. 相似文献
363.
This article develops an ecological theory that shifts the paradigm of professional mobilization from causes to relational spaces. It analyzes different species of activist professionals by locating them in an ecology of activism and examining how collective action emerges from their boundary work with the ecology's increasing density and consolidation. It empirically grounds the theory by explaining the political activism of Chinese lawyers in the early twenty‐first century and how it led to a government crackdown in 2015. Using interviews, online ethnography, and archival data collected from 2005 to 2017, the research demonstrates that Chinese lawyers’ political mobilization has experienced three stages: (1) vacancy and isolation (2000–2007), (2) spatial consolidation (2008–2011), and (3) boundary work (2011–2015). The study has implications for theories of social space and for understanding professional mobilization in authoritarian contexts and beyond. 相似文献
364.
Brizzi Francesco Birrell Paul J. Plummer Martyn T. Kirwan Peter Brown Alison E. Delpech Valerie C. Gill O. Noel De Angelis Daniela 《Lifetime data analysis》2019,25(4):757-780
Lifetime Data Analysis - CD4-based multi-state back-calculation methods are key for monitoring the HIV epidemic, providing estimates of HIV incidence and diagnosis rates by disentangling their... 相似文献
365.
Erin C. Adams 《Social Studies》2019,110(3):131-145
This is a comprehensive review of literature related to K-12 economics curriculum spanning 20 years, from 1998-2018. The search for literature revealed 18 articles and book chapters in peer-reviewed journals and volumes related to social studies and economics education. The study revealed several trends and issues related to K-12 economics textbooks, including publishing trends, the extent to which economics curriculum is relevant and enactive, and the influence of neoclassical economic theory in serving as the “official knowledge” undergirding the curriculum. The review presents debates in the field related to these issues. The study also reveals the possible influence of the 2008 financial crisis, revealing that economics curriculum seems to have changed little, although the number of scholars critiquing the curriculum has risen dramatically. 相似文献
366.
Cameron C. Brown Zenova Williams Jared A. Durtschi 《Journal of marital and family therapy》2019,45(4):650-667
Minimal research has examined interracial couples’ relationship satisfaction and dissolution patterns over time. Using dyadic data across 8 years, we examined potential differences in relationship quality trajectories through latent growth curve modeling with 1,336 couples as well as differential risks for relationship dissolution through logistic regression between same‐race and interracial relationships using a different subset of 2,370 couples. Results indicated that women in interracial relationships were significantly lower in initial relationship quality than women in same‐race relationships. Further, interracial couples of Black‐Hispanic partnerings were twice as likely to separate across 8 years than same‐race couples. These results suggest that despite interracial relationships not substantively differing from same‐race couples in trajectories of relationship quality, specific Black‐Hispanic interracial couples are at a higher risk of eventual separation. 相似文献
367.
We analyse 4300 advertisements of children featured in the Today's Child column, a daily written by Helen Allen in The Toronto Telegram and The Toronto Star from 1964 to 1982, to understand how the Canadian public became accepting of the adoption of Indigenous children. While children of all ethnic backgrounds were featured, the Indigenous children who were displayed were part of a larger system of child removal, known as the ‘Sixties Scoop’. We demonstrate the ways Indigenous children are described with a specific form of happiness that is conjoined with colonial conceptions of the family and nation. 相似文献
368.
Anthony Y. C. Kuk 《Journal of Statistical Computation and Simulation》2019,89(11):2138-2150
In survival analysis, one way to deal with non-proportional hazards is to model short-term and long-term hazard ratios. The existing model of this nature has no control over how fast the hazard ratio is changing over time. We add a parameter to the existing model to allow the hazard ratio to change over time at different speed. A nonparametric maximum likelihood approach is used to estimate the model parameters. The existing model is a special case of the extended model when the speed parameter is 0, which leads naturally to a way of testing the adequacy of the existing model. Simulation results show that there can be substantial bias in the estimation of the short-term and long-term hazard ratio if the speed parameter is fixed incorrectly at 0 rather than estimated. The extended model is fitted to three real data sets to shed new insights, including the observation that converging hazards does not necessarily imply the odds are proportional. 相似文献
369.
In recent decades, quantile regression has received much more attention from academics and practitioners. However, most of existing computational algorithms are only effective for small or moderate size problems. They cannot solve quantile regression with large-scale data reliably and efficiently. To this end, we propose a new algorithm to implement quantile regression on large-scale data using the sparse exponential transform (SET) method. This algorithm mainly constructs a well-conditioned basis and a sampling matrix to reduce the number of observations. It then solves a quantile regression problem on this reduced matrix and obtains an approximate solution. Through simulation studies and empirical analysis of a 5% sample of the US 2000 Census data, we demonstrate efficiency of the SET-based algorithm. Numerical results indicate that our new algorithm is effective in terms of computation time and performs well for large-scale quantile regression. 相似文献
370.
D. C. Wickramarachchi B. L. Robertson M. Reale C. J. Price J. A. Brown 《Australian & New Zealand Journal of Statistics》2019,61(3):380-391
We present an algorithm for learning oblique decision trees, called HHCART(G). Our decision tree combines learning concepts from two classification trees, HHCART and Geometric Decision Tree (GDT). HHCART(G) is a simplified HHCART algorithm that uses linear structure in the training examples, captured by a modified GDT angle bisector, to define splitting directions. At each node, we reflect the training examples with respect to the modified angle bisector to align this linear structure with the coordinate axes. Searching axis parallel splits in this reflected feature space provides an efficient and effective way of finding oblique splits in the original feature space. Our method is much simpler than HHCART because it only considers one reflected feature space for node splitting. HHCART considers multiple reflected feature spaces for node splitting making it more computationally intensive to build. Experimental results show that HHCART(G) is an effective classifier, producing compact trees with similar or better results than several other decision trees, including GDT and HHCART trees. 相似文献