全文获取类型
收费全文 | 11828篇 |
免费 | 373篇 |
国内免费 | 110篇 |
专业分类
管理学 | 372篇 |
劳动科学 | 2篇 |
民族学 | 113篇 |
人才学 | 1篇 |
人口学 | 243篇 |
丛书文集 | 1383篇 |
理论方法论 | 627篇 |
综合类 | 7200篇 |
社会学 | 853篇 |
统计学 | 1517篇 |
出版年
2024年 | 29篇 |
2023年 | 107篇 |
2022年 | 85篇 |
2021年 | 125篇 |
2020年 | 154篇 |
2019年 | 134篇 |
2018年 | 193篇 |
2017年 | 215篇 |
2016年 | 229篇 |
2015年 | 229篇 |
2014年 | 543篇 |
2013年 | 1071篇 |
2012年 | 655篇 |
2011年 | 722篇 |
2010年 | 604篇 |
2009年 | 594篇 |
2008年 | 651篇 |
2007年 | 727篇 |
2006年 | 808篇 |
2005年 | 719篇 |
2004年 | 701篇 |
2003年 | 646篇 |
2002年 | 542篇 |
2001年 | 463篇 |
2000年 | 284篇 |
1999年 | 105篇 |
1998年 | 55篇 |
1997年 | 52篇 |
1996年 | 40篇 |
1995年 | 53篇 |
1994年 | 23篇 |
1993年 | 20篇 |
1992年 | 15篇 |
1991年 | 21篇 |
1990年 | 15篇 |
1989年 | 14篇 |
1988年 | 14篇 |
1987年 | 5篇 |
1986年 | 2篇 |
1985年 | 100篇 |
1984年 | 113篇 |
1983年 | 77篇 |
1982年 | 79篇 |
1981年 | 62篇 |
1980年 | 75篇 |
1979年 | 61篇 |
1978年 | 59篇 |
1977年 | 8篇 |
1976年 | 10篇 |
1973年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
Logarithmic general error distribution, an extension of the log-normal distribution, is proposed. Some interesting properties of the log GED are derived. These properties are applied to establish the asymptotic behavior of the ratio of probability densities and the ratio of the tails of the logarithmic general error and log-normal distributions, and to derive the asymptotic distribution of the partial maximum of an independent and identically distributed sequence obeying the log GED. 相似文献
222.
《考工记》是两千多年前由齐国人编纂的一部手工业科技文献,也是目前中国所见年代最早的有关手工业制造及工艺技术的记述。早在1996年,在齐文化发源地山东淄博召开的“第一届中国科技典籍国际会议”上,学者们就此书的科学价值发表了多篇论文,形成了《考工记》研究的一个高潮。重温这部我国手工业制造编纂史的奠基之作,对指导科技档案工作仍有重要的现实意义。 相似文献
223.
In this paper, we propose a multiple deferred state repetitive group sampling plan which is a new sampling plan developed by incorporating the features of both multiple deferred state sampling plan and repetitive group sampling plan, for assuring Weibull or gamma distributed mean life of the products. The quality of the product is represented by the ratio of true mean life and specified mean life of the products. Two points on the operating characteristic curve approach is used to determine the optimal parameters of the proposed plan. The plan parameters are determined by formulating an optimization problem for various combinations of producer's risk and consumer's risk for both distributions. The sensitivity analysis of the proposed plan is discussed. The implementation of the proposed plan is explained using real-life data and simulated data. The proposed plan under Weibull distribution is compared with the existing sampling plans. The average sample number (ASN) of the proposed plan and failure probability of the product are obtained under Weibull, gamma and Birnbaum–Saunders distributions for a specified value of shape parameter and compared with each other. In addition, a comparative study is made between the ASN of the proposed plan under Weibull and gamma distributions. 相似文献
224.
Measures of statistical divergence are used to assess mutual similarities between distributions of multiple variables through a variety of methodologies including Shannon entropy and Csiszar divergence. Modified measures of statistical divergence are introduced throughout the present article. Those modified measures are related to the Lin–Wong (LW) divergence applied on the past lifetime data. Accordingly, the relationship between Fisher information and the LW divergence measure was explored when applied on the past lifetime data. Throughout this study, a number of relations are proposed between various assessment methods which implement the Jensen–Shannon, Jeffreys, and Hellinger divergence measures. Also, relations between the LW measure and the Kullback–Leibler (KL) measures for past lifetime data were examined. Furthermore, the present study discusses the relationship between the proposed ordering scheme and the distance interval between LW and KL measures under certain conditions. 相似文献
225.
Development of predictive signatures for treatment selection in precision medicine with survival outcomes 下载免费PDF全文
For survival endpoints in subgroup selection, a score conversion model is often used to convert the set of biomarkers for each patient into a univariate score and using the median of the univariate scores to divide the patients into biomarker‐positive and biomarker‐negative subgroups. However, this may lead to bias in patient subgroup identification regarding the 2 issues: (1) treatment is equally effective for all patients and/or there is no subgroup difference; (2) the median value of the univariate scores as a cutoff may be inappropriate if the sizes of the 2 subgroups are differ substantially. We utilize a univariate composite score method to convert the set of patient's candidate biomarkers to a univariate response score. We propose applying the likelihood ratio test (LRT) to assess homogeneity of the sampled patients to address the first issue. In the context of identification of the subgroup of responders in adaptive design to demonstrate improvement of treatment efficacy (adaptive power), we suggest that subgroup selection is carried out if the LRT is significant. For the second issue, we utilize a likelihood‐based change‐point algorithm to find an optimal cutoff. Our simulation study shows that type I error generally is controlled, while the overall adaptive power to detect treatment effects sacrifices approximately 4.5% for the simulation designs considered by performing the LRT; furthermore, the change‐point algorithm outperforms the median cutoff considerably when the subgroup sizes differ substantially. 相似文献
226.
为了让习近平新时代中国特色社会主义思想“进教材、进课堂、进头脑”,需要从方式、方法层面进行分析。在深耕教材的基础上,发现2018版《马克思主义基本原理概论》教材在融入习思想时,依据不同内容主要采取了文献参考式、引入说明式、说明原理式、补充创新式、替代更新式等方法。为有效做好教材体系向教学体系转换,针对教材中对习思想融入的不同方式,可以因内容分别或组合选择活动拓展法、课前一语法、习近平话语中心式教学法、问题式教学法、案例教学法等。在转化过程中,在方法论上必须坚持马克思主义辩证法,具体问题具体分析,做到转化有法但无定法;在转化的内容和方法的关系上,必须坚持内容和方法的有机统一,从习思想和教材整体视角审视转化,处理好整体与部分的关系;在思政课的价值引领方面,必须处理好真理与价值的关系,把转化最终落脚于价值转化,使习思想真正入脑、入心。 相似文献
227.
《Women and birth : journal of the Australian College of Midwives》2021,34(4):303-305
In this call to action, a coalition of Indigenous and non-Indigenous researchers from Australia, Aotearoa New Zealand, United States and Canada argue for the urgent need for adequately funded Indigenous-led solutions to perinatal health inequities for Indigenous families in well-resourced settler-colonial countries. Authors describe examples of successful community-driven programs making a difference and call on all peoples to support and resource Indigenous-led perinatal health services by providing practical actions for individuals and different groups. 相似文献
228.
Survival bias is a long recognized problem in case–control studies, and many varieties of bias can come under this umbrella term. We focus on one of them, termed Neyman's bias or ‘prevalence–incidence bias’. It occurs in case–control studies when exposure affects both disease and disease-induced mortality, and we give a formula for the observed, biased odds ratio under such conditions. We compare our result with previous investigations into this phenomenon and consider models under which this bias may or may not be important. Finally, we propose three hypothesis tests to identify when Neyman's bias may be present in case–control studies. We apply these tests to three data sets, one of stroke mortality, another of brain tumors, and the last of atrial fibrillation, and find some evidence of Neyman's bias in the former two cases, but not the last case. 相似文献
229.
Jiantian Wang 《统计学通讯:理论与方法》2018,47(1):55-63
This paper studies the likelihood ratio ordering of parallel systems under multiple-outlier models. We introduce a partial order, the so-called θ-order, and show that the θ-order between the parameter vectors of the parallel systems implies the likelihood ratio order between the systems. 相似文献
230.
This paper presents some powerful omnibus tests for multivariate normality based on the likelihood ratio and the characterizations of the multivariate normal distribution. The power of the proposed tests is studied against various alternatives via Monte Carlo simulations. Simulation studies show our tests compare well with other powerful tests including multivariate versions of the Shapiro–Wilk test and the Anderson–Darling test. 相似文献