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   8800篇
  免费   205篇
  国内免费   2篇
管理学   1334篇
民族学   33篇
人口学   774篇
丛书文集   26篇
理论方法论   824篇
综合类   96篇
社会学   4424篇
统计学   1496篇
  2020年   100篇
  2019年   149篇
  2018年   178篇
  2017年   194篇
  2016年   175篇
  2015年   131篇
  2014年   190篇
  2013年   1561篇
  2012年   213篇
  2011年   239篇
  2010年   183篇
  2009年   176篇
  2008年   214篇
  2007年   205篇
  2006年   216篇
  2005年   213篇
  2004年   182篇
  2003年   142篇
  2002年   185篇
  2001年   180篇
  2000年   193篇
  1999年   169篇
  1998年   153篇
  1997年   140篇
  1996年   145篇
  1995年   140篇
  1994年   147篇
  1993年   146篇
  1992年   144篇
  1991年   162篇
  1990年   176篇
  1989年   150篇
  1988年   165篇
  1987年   148篇
  1986年   139篇
  1985年   146篇
  1984年   155篇
  1983年   139篇
  1982年   105篇
  1981年   86篇
  1980年   87篇
  1979年   118篇
  1978年   92篇
  1977年   64篇
  1976年   85篇
  1975年   58篇
  1974年   73篇
  1973年   53篇
  1972年   48篇
  1971年   50篇
排序方式: 共有9007条查询结果,搜索用时 46 毫秒
1.
2.
The paper provides a method for generating epoch estimates for time series survey data, allowing for different periods of time (or even point estimates) according to user demand. The method uses a modified kriging estimator, which suppresses the contribution of sampling error variability in order to guarantee that custom epoch estimates have an interpolation property. For the veteran population variable of the American Community Survey, we utilize a simple Brownian Motion model of the population process and derive the modified kriging estimator for this case. The tuning parameters of this population model can be calibrated to the data via simple formulas. We illustrate the application of this method to the generation of point estimates of veteran population, an important objective for Veterans Affairs.  相似文献   
3.
Objectives: In the United States, HIV continues to disproportionately affect men who have sex with men. One promising area of research that may inform the development of behavioral interventions among male–male couples is within the realm of sexual agreements. Methods: The purpose of our analysis was to determine whether respondents who report having an open agreement or an agreement breakage also report a higher incidence of recent (within the previous 12 months) intimate-partner violence (IPV) compared to respondents who report having a monogamous agreement or no agreement breakage after controlling for demographic variables. Results: Results showed that men who have an open agreement are less likely to report recent physical IPV. Conclusions: The results highlight the need to develop dyadic behavior interventions that address sexual agreements and stress management.  相似文献   
4.
This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei.  相似文献   
5.
The current study examined the role of hypothalamic‐pituitary‐adrenal reactivity (a physiological indicator of stress) in early infancy as a mediator of the relationship between maternal postpartum depression and toddler behavior problems. Participants were 137 at‐risk mothers and their children participating in a longitudinal study of intergenerational transmission of risk. Mothers’ depression was measured five times during the infants’ first 18 months. Infant cortisol was collected during a social stressor (the still‐face paradigm) when infants were 6 months old, and mothers reported on toddlers’ internalizing and externalizing symptoms at 18 months. Among this sample of high‐risk mother–infant dyads, early postpartum depression predicted atypical infant cortisol reactivity at 6 months, which mediated the effect of maternal depression on increased toddler behavior problems. Clinical implications are discussed.  相似文献   
6.
Population Research and Policy Review - The welfare state can be perceived as a safety net which helps individuals adjust to situations of risk or transition. Starting from this idea of the welfare...  相似文献   
7.
8.
9.
We find “green” labels increase residential property values by an average of 5%. This premium varies by label stringency and across market segments. Builders respond to the stringency of labels by strategically incorporating green features to achieve higher ratings. This strategy seems reasonable as there is no market premium for green features that lead to scores between label rating cutoff values. These results raise important questions as to how green label policies should be designed in order to foster the supply of green features. Gradations of green attributes are influential, particularly for highly rated homes. The most stringent labels have the greatest role at the high price end of the market. (JEL Q20, Q40, R31)  相似文献   
10.
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