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   23633篇
  免费   718篇
  国内免费   1篇
管理学   3235篇
民族学   140篇
人才学   1篇
人口学   2146篇
丛书文集   102篇
教育普及   2篇
理论方法论   2254篇
综合类   231篇
社会学   12003篇
统计学   4238篇
  2023年   141篇
  2022年   91篇
  2021年   158篇
  2020年   400篇
  2019年   586篇
  2018年   679篇
  2017年   906篇
  2016年   694篇
  2015年   474篇
  2014年   644篇
  2013年   4196篇
  2012年   857篇
  2011年   820篇
  2010年   594篇
  2009年   528篇
  2008年   659篇
  2007年   621篇
  2006年   658篇
  2005年   535篇
  2004年   543篇
  2003年   455篇
  2002年   485篇
  2001年   557篇
  2000年   496篇
  1999年   492篇
  1998年   372篇
  1997年   328篇
  1996年   360篇
  1995年   344篇
  1994年   302篇
  1993年   312篇
  1992年   352篇
  1991年   352篇
  1990年   343篇
  1989年   307篇
  1988年   283篇
  1987年   246篇
  1986年   284篇
  1985年   303篇
  1984年   274篇
  1983年   236篇
  1982年   195篇
  1981年   173篇
  1980年   190篇
  1979年   215篇
  1978年   174篇
  1977年   146篇
  1976年   124篇
  1975年   133篇
  1974年   123篇
排序方式: 共有10000条查询结果,搜索用时 453 毫秒
111.
Summary.  Factor analysis is a powerful tool to identify the common characteristics among a set of variables that are measured on a continuous scale. In the context of factor analysis for non-continuous-type data, most applications are restricted to item response data only. We extend the factor model to accommodate ranked data. The Monte Carlo expectation–maximization algorithm is used for parameter estimation at which the E-step is implemented via the Gibbs sampler. An analysis based on both complete and incomplete ranked data (e.g. rank the top q out of k items) is considered. Estimation of the factor scores is also discussed. The method proposed is applied to analyse a set of incomplete ranked data that were obtained from a survey that was carried out in GuangZhou, a major city in mainland China, to investigate the factors affecting people's attitude towards choosing jobs.  相似文献   
112.
113.
114.
Relations between grandmother and partner involvement (coresidence, social support, child care) and Puerto Rican adolescent mothers' parenting behaviors were examined. Few associations between grandmother involvement and behavior emerged, and these were moderated by coresidence. In contrast, partner involvement showed a number of significant (positive) direct and moderated relations with behavior. For both providers, the direction of the relations between social support and behavior during teaching was the opposite depending on coresidence: Greater social support was related to the display of more positive behavior among coresiding mothers but to less competent behavior among non‐coresiding mothers. The relations between child care support and behavior differed across providers. For grandmothers, greater child care was related to less positive behavior during teaching among coresiding mothers but to more competent behavior among non‐coresiding mothers. For partners, greater child care was more strongly related to positive behavior during play among non‐coresiding than coresiding mothers. Results are discussed in light of Latino cultural values, developmental issues, and implications for intervention.  相似文献   
115.
Summary. Using a novel method, the paper investigates the influence of social group identities on attitudes and on voting in a variety of political contexts. Examining the major regions of Britain, Canada and the USA, we find considerable national and regional diversity in the nature of social cleavages. For example, social class and race had widely different effects across societies, but within societies their effects on attitudes and on voting were very similar. However, despite that, age and religion had a similar effect on attitudes across societies; the effects on voting varied considerably. The significant within-country differences underline the importance of using region, rather than country, as the unit of analysis. More importantly, these results highlight the role of political context, especially competing cleavages and the structure of party competition, in the establishment of politically relevant social cleavages.  相似文献   
116.
Silphids in urban forests: Diversity and function   总被引:2,自引:0,他引:2  
Wolf  Jordan M.  Gibbs  James P. 《Urban Ecosystems》2004,7(4):371-384
Many ecologists have examined the process of how urbanization reduces biological diversity but rarely have its ecological consequences been assessed. We studied forest-dwelling burying beetles (Coleoptera: Silphidae)—a guild of insects that requires carrion to complete their life cycles—along an urban-rural gradient of land use in Maryland. Our objective was to determine how forest fragmentation associated with urbanization affects (1) beetle community diversity and structure and (2) the ecological function provided by these insects, that is, decomposition of vertebrate carcasses. Forest fragmentation strongly reduced burying beetle diversity and abundance, and did so far more pervasively than urbanization of the surrounding landscape. The likelihood that beetles interred experimental baits was a direct, positive function of burying beetle diversity. We conclude that loss of burying beetle diversity resulting from forest fragmentation could have important ecological consequences in urban forests.  相似文献   
117.
We re-evaluate Andreu and Spanos's findings in favour of trend stationarity by considering the extended Nelson-Plosser data set. This expanded (to 1988) data set includes a period of rather different behaviour compared with the original Nelson-Plosser data used by Andreou and Spanos. We find that Andreou and Spanos's models (with only minor adjustments) exhibit remarable stability over this extended period, and indicate that their conclusions are more robust than they have shown.  相似文献   
118.
119.
Using findings from a study of the world of the wives of professional athletes, this article explores the complex motivations for and displays of trust, rapport, and group acceptance during ethnographic research. Episodic exchanges between a male ethnographer and female collaborators revealed subtle issues of gender and perceived relative worth. This article proposes the outsider strategy of “muted masculinity” as a means of exploring ethnographic issues in which the boundaries between insiders and outsiders are uncertain.  相似文献   
120.
Not having a variance estimator is a seriously weak point of a sampling design from a practical perspective. This paper provides unbiased variance estimators for several sampling designs based on inverse sampling, both with and without an adaptive component. It proposes a new design, which is called the general inverse sampling design, that avoids sampling an infeasibly large number of units. The paper provide estimators for this design as well as its adaptive modification. A simple artificial example is used to demonstrate the computations. The adaptive and non‐adaptive designs are compared using simulations based on real data sets. The results indicate that, for appropriate populations, the adaptive version can have a substantial variance reduction compared with the non‐adaptive version. Also, adaptive general inverse sampling with a limitation on the initial sample size has a greater variance reduction than without the limitation.  相似文献   
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