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   16026篇
  免费   441篇
  国内免费   54篇
管理学   1653篇
劳动科学   14篇
民族学   134篇
人才学   4篇
人口学   1220篇
丛书文集   888篇
理论方法论   1235篇
综合类   2349篇
社会学   5938篇
统计学   3086篇
  2023年   83篇
  2022年   114篇
  2021年   166篇
  2020年   243篇
  2019年   295篇
  2018年   412篇
  2017年   541篇
  2016年   372篇
  2015年   368篇
  2014年   444篇
  2013年   2498篇
  2012年   645篇
  2011年   615篇
  2010年   589篇
  2009年   513篇
  2008年   508篇
  2007年   529篇
  2006年   559篇
  2005年   509篇
  2004年   321篇
  2003年   347篇
  2002年   387篇
  2001年   442篇
  2000年   365篇
  1999年   342篇
  1998年   235篇
  1997年   203篇
  1996年   256篇
  1995年   225篇
  1994年   227篇
  1993年   184篇
  1992年   207篇
  1991年   218篇
  1990年   201篇
  1989年   180篇
  1988年   206篇
  1987年   185篇
  1986年   148篇
  1985年   181篇
  1984年   186篇
  1983年   165篇
  1982年   125篇
  1981年   95篇
  1980年   101篇
  1979年   115篇
  1978年   87篇
  1977年   75篇
  1975年   61篇
  1974年   65篇
  1973年   57篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.

Motivated by a breast cancer research program, this paper is concerned with the joint survivor function of multiple event times when their observations are subject to informative censoring caused by a terminating event. We formulate the correlation of the multiple event times together with the time to the terminating event by an Archimedean copula to account for the informative censoring. Adapting the widely used two-stage procedure under a copula model, we propose an easy-to-implement pseudo-likelihood based procedure for estimating the model parameters. The approach yields a new estimator for the marginal distribution of a single event time with semicompeting-risks data. We conduct both asymptotics and simulation studies to examine the proposed approach in consistency, efficiency, and robustness. Data from the breast cancer program are employed to illustrate this research.

  相似文献   
2.
In this paper we study the m-clique free interval subgraphs. We investigate the facial structure of the polytope defined as the convex hull of the incidence vectors associated with these subgraphs. We also present some facet-defining inequalities to strengthen the associated linear relaxation. As an application, the generalized open-shop problem with disjunctive constraints (GOSDC) is considered. Indeed, by a projection on a set of variables, the m-clique free interval subgraphs represent the solution of an integer linear program solving the GOSDC presented in this paper. Moreover, we propose exact and heuristic separation algorithms, which are exploited into a Branch-and-cut algorithm for solving the GOSDC. Finally, we present and discuss some computational results.  相似文献   
3.
According to the data of the Chinese Longitudinal Healthy Longevity Survey(CLHLS)and applyin g methods of Sullivan and multistate life table,this paper examines the time expectancy of care for daily living of Chinese elderly and its proportion in their elderly life.The results find that there exists a signifi cant gender gap of the expectancy,which the male at 65averagely are expected to have four to five care years while the female at 65averagely are expected to have seven to eight care years.The time expectancy for slight care of daily living is longer than that for sever care.Additionally,there is no significant difference between urban elderly and rural elderly.However,as age increases,the time expectancy for slight care goes down while that for sever care stabilities at a constant at different ages.The time expectancy for different types of care and its proportion in the rest of life are significantly various.The study points out that the establishment and improvement of care insurance system and the elderly care service are very necessary.  相似文献   
4.
5.
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Organizational transparency has become a prominent concern for the nonprofit sector as it expands globally. Transparency...  相似文献   
6.
康晓光  卢宪英 《学术界》2015,(1):135-150,325
"儒家文化的命运"关系到每个中国人的安身立命,关系到中华民族和中国的命运,关系到人类和世界格局及其发展趋势。本文以10个样本城市1254个样本的经验数据为根据,澄清了两个诉说纷纭的问题:一,儒家文化的生存状态,它是一成不变地保留下来了,还是已经彻底消亡,抑或是处于一种折中状态?二,近年出现的传统文化复兴现象的性质,它是一个暂时的现象,还是一个长期历史趋势的开端?实证分析表明:一、儒家文化的生存状态,既不是张之洞所言的"一成不变",也不是列文森所言的"彻底消亡"。在经历了一个半世纪的被妖魔化的历史之后,经过损益的儒家文化仍然活着。二、近年来出现的传统文化复兴现象,不是一场误会,而是历史的必然;不是稍纵即逝的泡沫,而是一个长期历史趋势的开端。儒家文化正迎来一个复兴的时代。儒家文化之所以在此时走上复兴之路,一是中国的终极文化具有超越时代的素质,这种素质孕育了其复兴的"可能性";二是中国的工具文化现代化获得了空前成功,这种成功创造了使可能转化为现实的"大势";三是当下的有利的现实的经济、政治、社会和国际条件。  相似文献   
7.
Drawing on employment records, qualitative interviews, and a survey, we explore the experiences of apprentices in the highway trades in Oregon. We demonstrate that female and racial/ethnic minority apprentices have lower rates of recruitment and retention and disproportionately face challenges with interpersonal interactions, hiring practices, and supervisory practices. Yet, we find a pervasive narrative that attributes apprentices' success to “hard work,” which contributes to the legitimacy of these inequalities. Consistent with the conceptualization of work organizations as inequality regimes, we argue that the apprenticeship system has policies, practices, and ideologies that are on the surface gender and race/ethnicity neutral, yet lead to the perpetuation of inequalities.  相似文献   
8.
Researchers have been developing various extensions and modified forms of the Weibull distribution to enhance its capability for modeling and fitting different data sets. In this note, we investigate the potential usefulness of the new modification to the standard Weibull distribution called odd Weibull distribution in income economic inequality studies. Some mathematical and statistical properties of this model are proposed. We obtain explicit expressions for the first incomplete moment, quantile function, Lorenz and Zenga curves and related inequality indices. In addition to the well-known stochastic order based on Lorenz curve, the stochastic order based on Zenga curve is considered. Since the new generalized Weibull distribution seems to be suitable to model wealth, financial, actuarial and especially income distributions, these findings are fundamental in the understanding of how parameter values are related to inequality. Also, the estimation of parameters by maximum likelihood and moment methods is discussed. Finally, this distribution has been fitted to United States and Austrian income data sets and has been found to fit remarkably well in compare with the other widely used income models.  相似文献   
9.
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   
10.

We analyze cooperation of individuals in a family context, using a Public Good game. In a lab experiment, 165 individuals from 55 three-generation families (youth, parent, and grandparent) play a repeated Public Good game in three different treatments: one in which three members of the same family play each other (family), a second with the youth and two non-family members, while preserving the previous generational structure (inter-generational), and a third in which three randomly-selected players play each other (random). We find that all the age groups cooperate more when playing with relatives, indicating that family ties may have a positive relationship to contributions to the Public Good. We also find that this trend is more evident for the youths and the parents than for the grandparents. Furthermore, young individuals tend to cooperate less than older generations, especially in non-family treatments. Our results serve as evidence of the relationship between family ties and inter-generational cooperative behaviors.

  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