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   8570篇
  免费   176篇
管理学   1226篇
民族学   29篇
人口学   856篇
丛书文集   27篇
理论方法论   670篇
综合类   110篇
社会学   3812篇
统计学   2016篇
  2021年   42篇
  2020年   129篇
  2019年   168篇
  2018年   235篇
  2017年   300篇
  2016年   203篇
  2015年   142篇
  2014年   206篇
  2013年   1448篇
  2012年   280篇
  2011年   281篇
  2010年   198篇
  2009年   187篇
  2008年   180篇
  2007年   211篇
  2006年   179篇
  2005年   185篇
  2004年   168篇
  2003年   161篇
  2002年   175篇
  2001年   213篇
  2000年   201篇
  1999年   177篇
  1998年   137篇
  1997年   134篇
  1996年   134篇
  1995年   116篇
  1994年   112篇
  1993年   104篇
  1992年   146篇
  1991年   123篇
  1990年   121篇
  1989年   118篇
  1988年   97篇
  1987年   96篇
  1986年   97篇
  1985年   114篇
  1984年   119篇
  1983年   126篇
  1982年   99篇
  1981年   92篇
  1980年   87篇
  1979年   98篇
  1978年   94篇
  1977年   83篇
  1976年   70篇
  1975年   69篇
  1974年   59篇
  1973年   58篇
  1971年   49篇
排序方式: 共有8746条查询结果,搜索用时 15 毫秒
841.
Three experiments investigated the role of prosodic structure for infants' recognition of embedded word sequences. Six‐month‐olds were familiarized with 2 versions of the same sequence, 1 corresponding to a well‐formed prosodic unit and the other to a prosodically ill‐formed sequence (although a successive word series). Next, infants heard 2 test passages. One included the well‐formed unit, and the other included the ill‐formed sequence. In Experiment 1, infants listened longer to the passage containing the well‐formed unit, suggesting that such units, even when they are embedded, are better recognized. Experiments 2 and 3 showed that this better recognition does not depend on an acoustic match between the familiarized sequences and their later embeddings. This suggests that the advantage of the well‐formed unit is at least partially due to infants' use of prosody to parse continuous speech.  相似文献   
842.
A German version of the Organizational Citizenship Behavior Questionnaire (GOCBQ) is developed and tested. Study 1 was conducted with 150 students working together in 39 project groups. The results show that the internal consistency and test-retest-reliability of the GOCBQ are good. Moreover, the GOCBQ measures a general altruism orientation which can be interpreted as a stable trait. The GOCBQ does neither correlate substantially with demographical variables nor with extroversion or neuroticism. Instead, substantial correlations are registered with mood and group atmosphere. In study 2 results from study 1 were cross-validated with data from 128 voluntary and professional helpers, in study 3 with data from 43 professionals. Implications for future research and applications in working life are discussed.  相似文献   
843.
For this exploratory study of the educational orientations of graduate social work faculty, the author surveyed faculty in 38 randomly selected graduate social work departments in the United States in Spring 1991. All were sent a revised Hadley Educational Orientation Questionnaire, which measured their agreement with 12 items each on Mentoring Orientation and Master Teaching Orientation scales. The survey also asked about the source of their educational philosophies. Analysis of 346 responses suggests that faculty tend toward a master teaching approach in attempting to impart essential knowledge and to empower students, but they also incorporate elements from the mentoring approach. Faculty indicated that their educational philosophies were derived principally from work experiences, personal experiences, and professional socialization.  相似文献   
844.
845.
The Gauss-Newton regression (GNR) is widely used to compute Lagrange multiplier statistics. A regression described by Milliken and Graybill yields an exact F test in a certain class of nonlinear models which are linear under the null. This paper shows that the Milliken-Graybill regression is a GNR. Hence one interpretation of Milliken-Graybill is that they identified a class of nonlinear models for which the GNR yields an exact test.  相似文献   
846.
This work is concerned with the Bayesian prediction problem of the number of components which will fail in a future time interval, when the failure times are Weibull distributed. Both the 1-sample and the 2-sample prediction problems are dealed with, and some choices of the prior densities on the distribution parameters are discussed which are relatively easy to work with and allow different degrees of knowledge on the failure mechanism to be incorporated in the predictive procedure. Useful relations between the predictive distribution on the number of future failures and the predictive distribution on the future failure times are derived. Numerical examples are also given.  相似文献   
847.
This note extends some results on homogeneous linear estimators to the general, even nonlinear case.A Sufficient condition for the difference of mean square error matrices of minimum conditional mean square error estimator and minimum average risk linear estimator to be postive definite is derived.  相似文献   
848.
Given p×n X N(βY, ∑?I), β, ∑ unknown, the noncentral multivariate beta density of the matrix L = [(YY′)-1/2Y X′ (XX′)-1XY′ (YY′)-1/2] is desired. Khatri (1964) finds this density when β is of rank unity. The present paper derives the noncentral density of L and the density of the roots matrix of L for full rank β. The dual case density of L is also obtained. The derivations are based on generalized Sverdrup's lemma, Kabe (1965), and the relationship between primal and dual density of L is explicitly established.  相似文献   
849.
In his recent paper, Ali (1991) has shown that the mixed regression estimator, when data contain mean-shift or variance inflation outliers, is uniformly superior to the ordinary least squares estimator in terms of scalar-valued mean square error. However, when using the matrix-valued mean square error criterion, this dominance fails to hold in general. The subsequent investigation gives a complete characterization of the situation where the mixed estimator is superior to the LS-estimator when the comparison is made with respect to this stronger MSE-property. Vice versa, the LS-estimator never dominates the mixed estimator relative to this criterion.  相似文献   
850.
Hader and Park (1978) introduced second order slope rotatability in axial directions. Park (1987) introduced second order slope rotatabilty over all directions. It is shown that these designs have the additional properly that the sum of the variances of estimates of slopes in all directions at any point is a function of the distance of the point from the design origin.  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