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   4321篇
  免费   119篇
  国内免费   3篇
管理学   490篇
民族学   26篇
人口学   386篇
丛书文集   26篇
理论方法论   314篇
综合类   86篇
社会学   1890篇
统计学   1225篇
  2023年   29篇
  2022年   20篇
  2021年   24篇
  2020年   72篇
  2019年   132篇
  2018年   114篇
  2017年   196篇
  2016年   116篇
  2015年   100篇
  2014年   119篇
  2013年   915篇
  2012年   145篇
  2011年   114篇
  2010年   79篇
  2009年   102篇
  2008年   96篇
  2007年   84篇
  2006年   73篇
  2005年   75篇
  2004年   68篇
  2003年   57篇
  2002年   85篇
  2001年   90篇
  2000年   76篇
  1999年   89篇
  1998年   76篇
  1997年   66篇
  1996年   56篇
  1995年   76篇
  1994年   55篇
  1993年   58篇
  1992年   68篇
  1991年   68篇
  1990年   74篇
  1989年   61篇
  1988年   43篇
  1987年   44篇
  1986年   50篇
  1985年   55篇
  1984年   56篇
  1983年   41篇
  1982年   37篇
  1981年   33篇
  1980年   40篇
  1979年   45篇
  1978年   37篇
  1977年   26篇
  1976年   21篇
  1974年   21篇
  1971年   21篇
排序方式: 共有4443条查询结果,搜索用时 93 毫秒
681.
682.
The results of a computer search for saturated designs for 2n factorial experiments with n runs is reported, (where n = 2 mod 4). A complete search of the design space is avoided by focussing on designs constructed from cyclic generators. A method of searching quickly for the best generators is given. The resulting designs are as good as, and sometimes better than, designs obtained via search algorithms reported in the literature. The addition of a further factor having three levels is also considered. Here, too, a complete search is avoided by restricting attention to the most efficient part of the design space under p-efficiency.  相似文献   
683.
Alternative ways of using Monte Carlo methods to implement a Cox-type test for separate families of hypotheses are considered. Monte Carlo experiments are designed to compare the finite sample performances of Pesaran and Pesaran's test, a RESET test, and two Monte Carlo hypothesis test procedures. One of the Monte Carlo tests is based on the distribution of the log-likelihood ratio and the other is based on an asymptotically pivotal statistic. The Monte Carlo results provide strong evidence that the size of the Pesaran and Pesaran test is generally incorrect, except for very large sample sizes. The RESET test has lower power than the other tests. The two Monte Carlo tests perform equally well for all sample sizes and are both clearly preferred to the Pesaran and Pesaran test, even in large samples. Since the Monte Carlo test based on the log-likelihood ratio is the simplest to calculate, we recommend using it.  相似文献   
684.
685.
686.
Drawing from Sorokin's hypothesis that socially mobile individuals are at greater risk of experiencing psychological distress than their non-mobile counterparts, we investigate whether intergenerational occupational mobility influences psychological distress, as measured by the Center for Epidemiologic Studies Depression (CES-D) scale. Using data for men from the Wisconsin Longitudinal Study (WLS) and Sobel's Diagonal Mobility Models, we find little evidence for Sorokin's hypothesis; mobile individuals are no more likely to be psychologically distressed than their non-mobile counterparts. In fact, one group of mobile men - those who left their farming origins - are actually less distressed than the sons who remain as farmers and non-mobile men in higher-ranked social classes. We speculate that this reflects the fact that farming became very arduous during the late 20th century and these mobile sons of farmers appreciate their improved life chances. Our findings suggest that the association between mobility and psychological distress varies across specific class backgrounds and is contingent upon the broader social and economic context.  相似文献   
687.
In an investigation of students' potential biases toward gay and lesbian instructors, 93 female and 59 male undergraduates viewed a lecture, rated the instructor and perceived learning, and completed a lecture-retention test. Lectures were given by a man or woman, identified as straight or gay or lesbian. Sexual orientation did not affect the instructor evaluation or perceived learning ratings for any of the groups. Although sexual orientation did not affect the lecture-retention scores for the female students, learning by the male students was significantly lower with the gay male instructor than with the straight male instructor (p = .03), suggesting an implicit bias.  相似文献   
688.
This study examines adolescent depressive symptoms and the quantity and quality of time spent by adolescents with their parents and siblings. We use measures of the quality of relationships with parents and siblings as proxy indicators for the quality of time spent with these social partners. The study emphasizes the salience of parent relationships to adolescent depression. The structural equation models suggest that time spent with parents is indirectly linked with the severity of depressive symptoms via adolescents’ perceptions of how accepting their parents are of them, and the extent to which parents avoid exerting psychological control. We discuss these findings in relation to clinical practice.  相似文献   
689.
Self-esteem is linked to high-risk behaviors in other populations but has not been examined in women aged 50 and older. This study explored how self-esteem is related to variables that can influence high-risk sexual behaviors in women over 50. A multiethnic community-based sample of 572 women aged 50 and older completed an anonymous questionnaire on sexual behaviors, sociodemographic characteristics, and psychosocial measures relevant to midlife and older women. Regression analysis showed sensation-seeking, HIV stigma, sexual assertiveness, and self-silencing predicted self-esteem in women over 50 (F = 43.632, p < .001). Factors such as relational context, interpersonal power, and silencing can affect self-esteem and may be contributing to HIV risk in this group.  相似文献   
690.
Price and design quality define value for customers and are often used by firms to position products in the marketplace. Setting price and quality level on a new product for the first time and making appropriate changes over time to these variables to reflect changing conditions in the market requires careful coordination of design, manufacturing, and marketing variables. We present a control theoretic model to study the complex interaction among price, quality, and cost during the life cycle of a product. Our model considers the major design-manufacturing-marketing tradeoffs and helps determine optimal pricing, design quality, and production strategies in a dynamic environment with convex production costs.  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