全文获取类型
收费全文 | 34744篇 |
免费 | 1007篇 |
国内免费 | 1篇 |
专业分类
管理学 | 4372篇 |
民族学 | 196篇 |
人才学 | 6篇 |
人口学 | 3226篇 |
丛书文集 | 170篇 |
教育普及 | 3篇 |
理论方法论 | 3219篇 |
现状及发展 | 1篇 |
综合类 | 394篇 |
社会学 | 17580篇 |
统计学 | 6585篇 |
出版年
2023年 | 192篇 |
2022年 | 154篇 |
2021年 | 210篇 |
2020年 | 566篇 |
2019年 | 888篇 |
2018年 | 972篇 |
2017年 | 1288篇 |
2016年 | 965篇 |
2015年 | 694篇 |
2014年 | 921篇 |
2013年 | 6026篇 |
2012年 | 1221篇 |
2011年 | 1160篇 |
2010年 | 866篇 |
2009年 | 780篇 |
2008年 | 964篇 |
2007年 | 911篇 |
2006年 | 900篇 |
2005年 | 756篇 |
2004年 | 764篇 |
2003年 | 684篇 |
2002年 | 703篇 |
2001年 | 835篇 |
2000年 | 727篇 |
1999年 | 720篇 |
1998年 | 569篇 |
1997年 | 501篇 |
1996年 | 524篇 |
1995年 | 533篇 |
1994年 | 474篇 |
1993年 | 467篇 |
1992年 | 543篇 |
1991年 | 531篇 |
1990年 | 512篇 |
1989年 | 462篇 |
1988年 | 452篇 |
1987年 | 396篇 |
1986年 | 414篇 |
1985年 | 449篇 |
1984年 | 420篇 |
1983年 | 398篇 |
1982年 | 318篇 |
1981年 | 270篇 |
1980年 | 302篇 |
1979年 | 320篇 |
1978年 | 259篇 |
1977年 | 237篇 |
1976年 | 197篇 |
1975年 | 199篇 |
1974年 | 175篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
Günter F. Müller 《Gruppendynamik und Organisationsberatung》2005,36(3):325-334
This paper outlines the conceptual bases, strategies, and psychological attributes of leadership by self-leadership. In addition, relations to other theories of leadership are drawn. Dimensions and correlates of self-leadership competence are described and discussed. Various approaches for developing self-leadership competence are discussed as well. 相似文献
72.
73.
Diane Hope Weixing Zhu Corinna Gries Jacob Oleson Jason Kaye Nancy B. Grimm Lawrence A. Baker 《Urban Ecosystems》2005,8(3-4):251-273
We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding
desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well
as for the desert and urban sites separately. Concentrations of both NO3-N and NH4-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO3-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious
surfaces and lawn, whereas soil NH4-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO3-N and NH4-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation
of soil NO3-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic
soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than
factors related to an urban-rural gradient. 相似文献
74.
A sample size justification should be given for all clinical investigations. However, sometimes the objective of a trial is to estimate an effect with a view to planning a later definitive study. This paper describes the calculations for designing studies where one wishes to adopt an estimation approach through using confidence intervals around the overall response. Calculations are given for data anticipated to take a Normal form. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
75.
Estimated associations between an outcome variable and misclassified covariates tend to be biased when the methods of estimation that ignore the classification error are applied. Available methods to account for misclassification often require the use of a validation sample (i.e. a gold standard). In practice, however, such a gold standard may be unavailable or impractical. We propose a Bayesian approach to adjust for misclassification in a binary covariate in the random effect logistic model when a gold standard is not available. This Markov Chain Monte Carlo (MCMC) approach uses two imperfect measures of a dichotomous exposure under the assumptions of conditional independence and non-differential misclassification. A simulated numerical example and a real clinical example are given to illustrate the proposed approach. Our results suggest that the estimated log odds of inpatient care and the corresponding standard deviation are much larger in our proposed method compared with the models ignoring misclassification. Ignoring misclassification produces downwardly biased estimates and underestimate uncertainty. 相似文献
76.
Professor Stephen Senn Dr Dipti Amin Professor Rosemary A. Bailey Professor Sheila M. Bird FFPH Dr Barbara Bogacka Mr Peter Colman Dr rew Garrett Professor rew Grieve Professor Sir Peter Lachmann FRS FMedSci 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2007,170(3):517-579
77.
78.
Has the image of Che Guevara lost its power to evoke radical politics in the face of pervasive commodification? The commercialization of this 1960s political icon has called into question the power of the market to shape collective memories. Meanwhile, antisystemic movements of the left continue to erect his image at protest events. In light of this contest over how Che Guevara is remembered, we investigate, using data from a survey of Spanish citizens, who is most likely to recall him. We find qualified support for the theory of generational imprinting—Che is more often recalled by those generations who saw him rise to prominence during their formative years, although prominent as a collective symbol rather than as a living person. Our results also corroborate the claim that historical figures or events are more salient for, and therefore more likely to be remembered by, some subgenerational units than others. Thus, although the younger generations are in general more likely than their elders to recall Che, he is most frequently remembered by the highly educated leftists who espouse postmaterialist and posttraditionalist values and identify more with their local regions than with the nation of Spain. These patterns suggest that, in contrast to the dire predictions of mass culture theorists, the memory of Che Guevara has become increasingly tied to markers of social, ethnic‐regional, and political identity. 相似文献
79.
Stephanie M. Pickle Timothy J. Robinson Jeffrey B. Birch Christine M. Anderson-Cook 《Journal of statistical planning and inference》2008
Parameter design or robust parameter design (RPD) is an engineering methodology intended as a cost-effective approach for improving the quality of products and processes. The goal of parameter design is to choose the levels of the control variables that optimize a defined quality characteristic. An essential component of RPD involves the assumption of well estimated models for the process mean and variance. Traditionally, the modeling of the mean and variance has been done parametrically. It is often the case, particularly when modeling the variance, that nonparametric techniques are more appropriate due to the nature of the curvature in the underlying function. Most response surface experiments involve sparse data. In sparse data situations with unusual curvature in the underlying function, nonparametric techniques often result in estimates with problematic variation whereas their parametric counterparts may result in estimates with problematic bias. We propose the use of semi-parametric modeling within the robust design setting, combining parametric and nonparametric functions to improve the quality of both mean and variance model estimation. The proposed method will be illustrated with an example and simulations. 相似文献
80.
Chunming M. Zhang 《Revue canadienne de statistique》2003,31(2):151-171
Many applications of nonparametric tests based on curve estimation involve selecting a smoothing parameter. The author proposes an adaptive test that combines several generalized likelihood ratio tests in order to get power performance nearly equal to whichever of the component tests is best. She derives the asymptotic joint distribution of the component tests and that of the proposed test under the null hypothesis. She also develops a simple method of selecting the smoothing parameters for the proposed test and presents two approximate methods for obtaining its P‐value. Finally, she evaluates the proposed test through simulations and illustrates its application to a set of real data. 相似文献