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   1586篇
  免费   43篇
  国内免费   12篇
管理学   59篇
劳动科学   1篇
民族学   17篇
人口学   30篇
丛书文集   142篇
理论方法论   115篇
综合类   952篇
社会学   167篇
统计学   158篇
  2024年   1篇
  2023年   12篇
  2022年   5篇
  2021年   4篇
  2020年   21篇
  2019年   29篇
  2018年   24篇
  2017年   26篇
  2016年   27篇
  2015年   37篇
  2014年   71篇
  2013年   179篇
  2012年   78篇
  2011年   74篇
  2010年   100篇
  2009年   58篇
  2008年   75篇
  2007年   94篇
  2006年   106篇
  2005年   103篇
  2004年   99篇
  2003年   106篇
  2002年   89篇
  2001年   112篇
  2000年   52篇
  1999年   15篇
  1998年   6篇
  1997年   7篇
  1996年   7篇
  1995年   6篇
  1994年   3篇
  1993年   4篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1989年   2篇
  1988年   2篇
  1987年   1篇
  1985年   1篇
  1983年   1篇
排序方式: 共有1641条查询结果,搜索用时 406 毫秒
31.
This study investigates the egocentric networks of underrepresented minority students. Adjustment to college for underrepresented minority students often means balancing between the origin (i.e., low-status family) and host (i.e., academic) environments, requiring students to develop different coping strategies. The analysis included 124 Roma university students. We employed the contact diary method and the EgoNet program for mapping students’ egocentric networks. We explored classification among egocentric networks by cluster analysis based on the network proportion of the origin, fellow, and host groups. Three clusters were distinguished. The Host-based cluster proved to be the most advantageous, while the Balancing cluster appeared to be the most disadvantageous in terms of network resources, well-being, and trust. Partners’ ethnicity and educational attainment showed a strong connection with cluster membership. Our results highlight that small fellow communities can successfully interconnect the origin and host groups in students’ egocentric networks.  相似文献   
32.
阿保机时代是契丹社会大变革的时代,阿保机变革旧制的一个内容就是对传统世选制的改造。经过他的努力,从理论意义上实现了契丹可汗世选向皇位世袭的转变,也对官吏的世选作了重大的调整。值得重视的是,阿保机的政治智慧在变革世选制过程中有所体现。  相似文献   
33.
ABSTRACT

Adjustment for nonresponse should reduce the nonresponse bias without decreasing the precision of the estimates. Adjustment for nonresponses are commonly based on socio-demographic variables, although these variables may be poorly correlated with response propensities and with variables of interest. Such variables nevertheless have the advantage of being available for all sample units, whether or not they are participating in the survey. Alternatively, adjustment for nonresponse can be obtained from a follow-up survey aimed at sample units which did not participate in the survey and from which the variables are designed to be correlated with response propensities. However, information collected through these follow-up surveys is not available for people in the sample who participated neither in the survey nor in its nonresponse follow-up. These two sets of variables when used in a nonresponse model for the Swiss European Social Survey 2012 differ only slightly with regard to their effect on bias correction and on the precision of estimates. The variables from the follow-up are performing slightly better. In both cases, the adjustment for nonresponse performs poorly.  相似文献   
34.
Binary response models are often applied in dose–response settings where the number of dose levels is limited. Commonly, one can find cases where the maximum likelihood estimation process for these models produces infinite values for at least one of the parameters, often corresponding to the ‘separated data’ issue. Algorithms for detecting such data have been proposed, but are usually incorporated directly into in the parameter estimation. Additionally, they do not consider the use of asymptotes in the model formulation. In order to study this phenomenon in greater detail, we define the class of specifiably degenerate functions where this can occur (including the popular logistic and Weibull models) that allows for asymptotes in the dose–response specification. We demonstrate for this class that the well-known pool-adjacent-violators algorithm can efficiently pre-screen for non-estimable data. A simulation study demonstrates the frequency with which this problem can occur for various response models and conditions.  相似文献   
35.
There is currently much discussion about lasso-type regularized regression which is a useful tool for simultaneous estimation and variable selection. Although the lasso-type regularization has several advantages in regression modelling, owing to its sparsity, it suffers from outliers because of using penalized least-squares methods. To overcome this issue, we propose a robust lasso-type estimation procedure that uses the robust criteria as the loss function, imposing L1-type penalty called the elastic net. We also introduce to use the efficient bootstrap information criteria for choosing optimal regularization parameters and a constant in outlier detection. Simulation studies and real data analysis are given to examine the efficiency of the proposed robust sparse regression modelling. We observe that our modelling strategy performs well in the presence of outliers.  相似文献   
36.
孔子以丰厚的学识修养锻炼出成熟丰富的心理调适策略:树立崇高的价值取向;构建学习型生活方式;培养高雅的生活情趣;固守正确的交友观念;保持幽默的人生态度。这些策略对当代教师具有重要的借鉴意义。  相似文献   
37.
In recent years, the migration of Spanish people to other countries in Europe has increased; however, there are hardly any studies on this phenomenon. The aim of this study is to identify the predictive sociodemographic and psychosocial factors of psychological adjustment (life satisfaction and absence of internalizing symptoms) of emigrants and to determine the indirect effects of these factors through perceived stress. This study also seeks to examine whether the psychological adjustment of Spanish emigrants was similar to Spanish non-emigrants. The sample was made up of a group of Spanish emigrants to Germany and England (n = 858) and an equivalent control group of Spanish non-emigrants (n = 328). The results show that fulfilment of expectations, emotional support and job quality are the best predictors of perceived stress and psychological adjustment. These factors are confirmed to have indirect effects on psychological adjustment through perceived stress. Finally, the mental health of emigrants and non-emigrants was similar, and the implications of these findings are discussed.  相似文献   
38.
The recently developed rolling year GEKS procedure makes maximum use of all matches in the data to construct nonrevisable price indexes that are approximately free from chain drift. A potential weakness is that unmatched items are ignored. In this article we use imputation Törnqvist price indexes as inputs into the rolling year GEKS procedure. These indexes account for quality changes by imputing the “missing prices” associated with new and disappearing items. Three imputation methods are discussed. The first method makes explicit imputations using a hedonic regression model which is estimated for each time period. The other two methods make implicit imputations; they are based on time dummy hedonic and time-product dummy regression models and are estimated on bilateral pooled data. We present empirical evidence for New Zealand from scanner data on eight consumer electronics products and find that accounting for quality change can make a substantial difference.  相似文献   
39.
近年来,我国社会转型加速,公务员面临的矛盾问题凸显,工作量和工作难度都空前加大,使其普遍感受到较大的心理压力,他们的心理比普通人更容易产生不稳定因素。从心理健康角度出发,研究国家公务员心理健康问题,探讨心理调适的方法,对于提升公务员的素质,提高执政能力具有非常重要的现实意义。  相似文献   
40.
孔子以丰厚的学识修养锻炼出成熟丰富的心理调适策略:树立崇高的价值取向;构建学习型生活方式;培养高雅的生活情趣;固守正确的交友观念;保持幽默的人生态度。这些策略对当代教师具有重要的借鉴意义。  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