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   40462篇
  免费   2555篇
  国内免费   1697篇
管理学   4792篇
劳动科学   1篇
民族学   588篇
人才学   4篇
人口学   3228篇
丛书文集   2075篇
教育普及   1篇
理论方法论   2712篇
综合类   10274篇
社会学   14043篇
统计学   6996篇
  2023年   206篇
  2022年   214篇
  2021年   399篇
  2020年   849篇
  2019年   1618篇
  2018年   1853篇
  2017年   2055篇
  2016年   1974篇
  2015年   1563篇
  2014年   1702篇
  2013年   6239篇
  2012年   2035篇
  2011年   1725篇
  2010年   1417篇
  2009年   1162篇
  2008年   1082篇
  2007年   916篇
  2006年   895篇
  2005年   864篇
  2004年   933篇
  2003年   812篇
  2002年   738篇
  2001年   881篇
  2000年   808篇
  1999年   675篇
  1998年   545篇
  1997年   489篇
  1996年   560篇
  1995年   463篇
  1994年   451篇
  1993年   477篇
  1992年   534篇
  1991年   508篇
  1990年   501篇
  1989年   458篇
  1988年   448篇
  1987年   420篇
  1986年   369篇
  1985年   414篇
  1984年   432篇
  1983年   400篇
  1982年   336篇
  1981年   267篇
  1980年   291篇
  1979年   356篇
  1978年   284篇
  1977年   260篇
  1976年   211篇
  1975年   231篇
  1974年   209篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
82.
Previous studies have shown that 7.5‐month‐olds can track and encode words in fluent speech, but they fail to equate instances of a word that contrast in talker gender, vocal affect, and fundamental frequency. By 10.5 months, they succeed at generalizing across such variability, marking a clear transition period during which infants' word recognition skills become qualitatively more mature. Here we explore the role of word familiarity in this critical transition and, in particular, whether words that occur frequently in a child's listening environment (i.e., “Mommy” and “Daddy”) are more easily recognized when they differ in surface characteristics than those that infants have not previously encountered (termed nonwords). Results demonstrate that words are segmented from continuous speech in a more linguistically mature fashion than nonwords at 7.5 months, but at 10.5 months, both words and nonwords are segmented in a relatively mature fashion. These findings suggest that early word recognition is facilitated in cases where infants have had significant exposure to items, but at later stages, infants are able to segment items regardless of their presumed familiarity.  相似文献   
83.
杜维明以哲学人类学的视角对儒学作出“创造性阐释”,把儒家哲学阐释为一种哲学的人类学。认为儒家的人性自我的实现除了需要内在主体在自我修养中不断深化外,还需要在外在人际关系的层层拓展与交互作用中进行创造性转换。但这种“创造性阐释”方法仅仅是观念的诠释,既不符合儒家思想的本意,也缺乏历史条件的支撑,更不可能在现代社会中实现创造性的转换。  相似文献   
84.
Summary: The H–family of distributions or H–distributions, introduced by Tukey (1960; 1977), are generated by a single transformation of the standard normal distribution and allow for leptokurtosis represented by the parameter h. Alternatively, Haynes et al. (1997) generated leptokurtic distributions by applying the K–transformation to the normal distribution. In this study we propose a third transformation, the so–called J–transformation, and derive some properties of this transformation. Moreover, so-called elongation generating functions (EGFs) are introduced. By means of EGFs we are able to visualize the strength of tail elongation and to construct new transformations. Finally, we compare the three transformations towards their goodness–of–fit in the context of financial return data.  相似文献   
85.
The 1998 Korean Survey of Family Income and Expenditures was used to examine the overall consumption and saving behavior of Korean baby boomers and compared the differences in consumption and saving behavior between older and younger boomers. The t -test results indicated that the younger boomers allocated a significantly higher percentage of their expenditures on food away from home, household appliances, transportation and communication than did the older boomers, whereas the older boomers spent higher amounts and allocated larger budget shares on their children's education than did the younger boomers. The results of Ordinary Least-Squares (OLS) regression analysis showed that, holding other factors constant, older boomers not only spent significantly more in the total consumption expenditures and education expenditures, but older boomers also saved significantly less than did younger boomers.  相似文献   
86.
What does sociology have to contribute to our understanding of terrorism? As scholars of gender and the Far Right, we believe that we have much to offer the current debates. In this article, we focus both on contemporary cases of terrorism, the attacks of September 11 and the Oklahoma City bombing, and terrorist movements as gendered: as enactments of masculinity. In particular, we focus on the contemporary white supremacist movement, the most dangerous domestic terrorist threat faced by the USA. We suggest that the ideology and organization of many terrorist groups are saturated with gendered meanings, both as the analytic prism through which they view their situation, and also as a means of political mobilization.  相似文献   
87.
We investigate how inequalities in political participation are shaped across generations by considering the influence of family background--in particular, parents' education and political involvement--on political participation. We pursue this issue, first, for individuals, investigating the effects of parental characteristics on the participatory profile of their offspring. Then, we use what we have learned to understand how group differences in political participation--between women and men and among Latinos, African Americans, and Anglo Whites--are rooted in the legacy of class and political background and in experiences throughout the life cycle.  相似文献   
88.
Expectations, Capital Gains, and Income   总被引:2,自引:0,他引:2  
A theoretical framework for the measurement of income under uncertainty is developed that addresses some long-standing controversies about the treatment of capital gains. The consequences for economic analysis and policy making are potentially serious, because the treatment of capital gains can significantly affect some major macroeconomic aggregates, including national income and savings, balance of payments deficits, government deficits, and depreciation. (JEL O47 , P44 , Q32 )  相似文献   
89.
Missing data, and the bias they can cause, are an almost ever‐present concern in clinical trials. The last observation carried forward (LOCF) approach has been frequently utilized to handle missing data in clinical trials, and is often specified in conjunction with analysis of variance (LOCF ANOVA) for the primary analysis. Considerable advances in statistical methodology, and in our ability to implement these methods, have been made in recent years. Likelihood‐based, mixed‐effects model approaches implemented under the missing at random (MAR) framework are now easy to implement, and are commonly used to analyse clinical trial data. Furthermore, such approaches are more robust to the biases from missing data, and provide better control of Type I and Type II errors than LOCF ANOVA. Empirical research and analytic proof have demonstrated that the behaviour of LOCF is uncertain, and in many situations it has not been conservative. Using LOCF as a composite measure of safety, tolerability and efficacy can lead to erroneous conclusions regarding the effectiveness of a drug. This approach also violates the fundamental basis of statistics as it involves testing an outcome that is not a physical parameter of the population, but rather a quantity that can be influenced by investigator behaviour, trial design, etc. Practice should shift away from using LOCF ANOVA as the primary analysis and focus on likelihood‐based, mixed‐effects model approaches developed under the MAR framework, with missing not at random methods used to assess robustness of the primary analysis. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
90.
Approximation formulae are developed for the bias of ordinary and generalized Least Squares Dummy Variable (LSDV) estimators in dynamic panel data models. Results from Kiviet [Kiviet, J. F. (1995), on bias, inconsistency, and efficiency of various estimators in dynamic panel data models, J. Econometrics68:53-78; Kiviet, J. F. (1999), Expectations of expansions for estimators in a dynamic panel data model: some results for weakly exogenous regressors, In: Hsiao, C., Lahiri, K., Lee, L-F., Pesaran, M. H., eds., Analysis of Panels and Limited Dependent Variables, Cambridge: Cambridge University Press, pp. 199-225] are extended to higher-order dynamic panel data models with general covariance structure. The focus is on estimation of both short- and long-run coefficients. The results show that proper modelling of the disturbance covariance structure is indispensable. The bias approximations are used to construct bias corrected estimators which are then applied to quarterly data from 14 European Union countries. Money demand functions for M1, M2 and M3 are estimated for the EU area as a whole for the period 1991: I-1995: IV. Significant spillovers between countries are found reflecting the dependence of domestic money demand on foreign developments. The empirical results show that in general plausible long-run effects are obtained by the bias corrected estimators. Moreover, finite sample bias, although of moderate magnitude, is present underlining the importance of more refined estimation techniques. Also the efficiency gains by exploiting the heteroscedasticity and cross-correlation patterns between countries are sometimes considerable.  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