全文获取类型
收费全文 | 8286篇 |
免费 | 246篇 |
国内免费 | 77篇 |
专业分类
管理学 | 402篇 |
民族学 | 31篇 |
人才学 | 4篇 |
人口学 | 71篇 |
丛书文集 | 675篇 |
理论方法论 | 161篇 |
综合类 | 5380篇 |
社会学 | 161篇 |
统计学 | 1724篇 |
出版年
2024年 | 16篇 |
2023年 | 46篇 |
2022年 | 54篇 |
2021年 | 54篇 |
2020年 | 90篇 |
2019年 | 159篇 |
2018年 | 164篇 |
2017年 | 241篇 |
2016年 | 181篇 |
2015年 | 241篇 |
2014年 | 417篇 |
2013年 | 813篇 |
2012年 | 570篇 |
2011年 | 484篇 |
2010年 | 457篇 |
2009年 | 426篇 |
2008年 | 469篇 |
2007年 | 537篇 |
2006年 | 556篇 |
2005年 | 460篇 |
2004年 | 407篇 |
2003年 | 358篇 |
2002年 | 305篇 |
2001年 | 292篇 |
2000年 | 190篇 |
1999年 | 95篇 |
1998年 | 86篇 |
1997年 | 68篇 |
1996年 | 48篇 |
1995年 | 58篇 |
1994年 | 54篇 |
1993年 | 44篇 |
1992年 | 36篇 |
1991年 | 22篇 |
1990年 | 22篇 |
1989年 | 33篇 |
1988年 | 21篇 |
1987年 | 15篇 |
1986年 | 8篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有8609条查询结果,搜索用时 15 毫秒
21.
Yue Fang 《Journal of statistical planning and inference》2003,110(1-2):55-73
Generalized method of moments (GMM) is used to develop tests for discriminating discrete distributions among the two-parameter family of Katz distributions. Relationships involving moments are exploited to obtain identifying and over-identifying restrictions. The asymptotic relative efficiencies of tests based on GMM are analyzed using the local power approach and the approximate Bahadur efficiency. The paper also gives results of Monte Carlo experiments designed to check the validity of the theoretical findings and to shed light on the small sample properties of the proposed tests. Extensions of the results to compound Poisson alternative hypotheses are discussed. 相似文献
22.
张留占 《山西农业大学学报(社会科学版)》2003,2(4):351-353,356
在法律基础课教学活动中 ,充分强调学生的主体作用 ,鼓励学生参与到每个教学环节。老师首先指出重点 ,引导阅读 ,然后指导学生讨论、讲解 ,最后总结 ,回答提问。其核心思想是教学活动中师生的“互动” ,提高学生分析问题和解决问题的能力 相似文献
23.
谈四六级考试改革后的课堂教学 总被引:3,自引:0,他引:3
范晓航 《郑州航空工业管理学院学报(社会科学版)》2007,26(4):135-137
文章主要从教学内容、教学模式、课时及测评等方面,探讨了四六级考试改革后的一些教学应对措施,以期对今后大学英语教学质量的提高有一定的促进作用。 相似文献
24.
Owing to the extreme quantiles involved, standard control charts are very sensitive to the effects of parameter estimation and non-normality. More general parametric charts have been devised to deal with the latter complication and corrections have been derived to compensate for the estimation step, both under normal and parametric models. The resulting procedures offer a satisfactory solution over a broad range of underlying distributions. However, situations do occur where even such a large model is inadequate and nothing remains but to consider non- parametric charts. In principle, these form ideal solutions, but the problem is that huge sample sizes are required for the estimation step. Otherwise the resulting stochastic error is so large that the chart is very unstable, a disadvantage that seems to outweigh the advantage of avoiding the model error from the parametric case. Here we analyse under what conditions non-parametric charts actually become feasible alternatives for their parametric counterparts. In particular, corrected versions are suggested for which a possible change point is reached at sample sizes that are markedly less huge (but still larger than the customary range). These corrections serve to control the behaviour during in-control (markedly wrong outcomes of the estimates only occur sufficiently rarely). The price for this protection will clearly be some loss of detection power during out-of-control. A change point comes in view as soon as this loss can be made sufficiently small. 相似文献
25.
李如春 《河北理工大学学报(社会科学版)》2003,3(3):83-84
论述投资控制的关键环节,提出投资控制工作的实施要点,阐明投资控制工作的必要性、可行性和重大意义. 相似文献
26.
蒋莉 《西昌学院学报(社会科学版)》2003,15(3):26-27
翻译涉及到语言和文化。本文从五个方面阐述了不同的文化观念给翻译带来的困难,并以举例的方式提出了解决这些困难的方法。 相似文献
27.
首先分析了对数最小二乘排序法的特点,说明它是一种值得重视的好方法;并进一步阐述了这一方法的基本原理,着重地对群体判断下求加权的综合排序向量的方法进行了严密的数学推导;提出了在加权的综合排序中权重系数确定的新見解,并举例子以解释。 相似文献
28.
John D. Emerson David C. Hoaglin Frederick Mosteller 《Statistical Methods and Applications》1993,2(3):269-290
Summary Meta-analyses of sets of clinical trials often combine risk differences from several 2×2 tables according to a random-effects
model. The DerSimonian-Laird random-effects procedure, widely used for estimating the populaton mean risk difference, weights
the risk difference from each primary study inversely proportional to an estimate of its variance (the sum of the between-study
variance and the conditional within-study variance). Because those weights are not independent of the risk differences, however,
the procedure sometimes exhibits bias and unnatural behavior. The present paper proposes a modified weighting scheme that
uses the unconditional within-study variance to avoid this source of bias. The modified procedure has variance closer to that
available from weighting by ideal weights when such weights are known. We studied the modified procedure in extensive simulation
experiments using situations whose parameters resemble those of actual studies in medical research. For comparison we also
included two unbiased procedures, the unweighted mean and a sample-size-weighted mean; their relative variability depends
on the extent of heterogeneity among the primary studies. An example illustrates the application of the procedures to actual
data and the differences among the results.
This research was supported by Grant HS 05936 from the Agency for Health Care Policy and Research to Harvard University. 相似文献
29.
关于线性互补问题的迭代算法 总被引:1,自引:0,他引:1
建立了一类求解线性互补问题的迭代算法。在一定条件下,研究了保证原问题的解存在唯一的充分条件,并且证明了新算法的收敛性。 相似文献
30.
采用射线跟踪和等效电流等方法计算金属垂直安定面的后向散射场和后向散射截面积(RCS)。对TM入射和TE入射在不同的入射角下求得数值结果。仔细分析了外形对后向RCS的影响,并提出压缩后向RCS的措施。 相似文献