全文获取类型
收费全文 | 1017篇 |
免费 | 31篇 |
国内免费 | 7篇 |
专业分类
管理学 | 70篇 |
人口学 | 9篇 |
丛书文集 | 23篇 |
理论方法论 | 14篇 |
综合类 | 254篇 |
社会学 | 12篇 |
统计学 | 673篇 |
出版年
2023年 | 8篇 |
2022年 | 19篇 |
2021年 | 10篇 |
2020年 | 33篇 |
2019年 | 47篇 |
2018年 | 54篇 |
2017年 | 64篇 |
2016年 | 39篇 |
2015年 | 33篇 |
2014年 | 56篇 |
2013年 | 181篇 |
2012年 | 90篇 |
2011年 | 40篇 |
2010年 | 30篇 |
2009年 | 35篇 |
2008年 | 30篇 |
2007年 | 40篇 |
2006年 | 25篇 |
2005年 | 24篇 |
2004年 | 30篇 |
2003年 | 22篇 |
2002年 | 23篇 |
2001年 | 21篇 |
2000年 | 14篇 |
1999年 | 18篇 |
1998年 | 15篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 3篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1978年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有1055条查询结果,搜索用时 953 毫秒
991.
Haiying Chen Elizabeth A. Stasny Douglas A. Wolfe 《Revue canadienne de statistique》2008,36(2):179-191
The authors show how ranked set sampling, both balanced and unbalanced, can be extended to ordered categorical variables with the goal of estimating the probabilities of all categories. They use ordinal logistic regression to aid in the ranking of the ordinal variable of interest. They also propose an optimal allocation scheme and methods for implementing it under either perfect or imperfect rankings. Results from a simulation study using data from the third National Health and Nutrition Examination Survey indicate that the use of ordinal logistic regression in ranking leads to substantial gains in precision for estimation of cell probabilities. 相似文献
992.
复变函数与积分变换课堂教学方法改革研究 总被引:1,自引:0,他引:1
主要介绍了复变函数与积分变换课堂教学改革的四方面的内容:合适的教材,学生的兴趣与能力的培养.理论背景及思想方法的重要性,双向交流和多种教学手段的运用. 相似文献
993.
994.
针对居民家庭消费与社会经济状况调查中户主自报的家庭固定收入可信程度差以及不同地区的不可比问题,利用陕西省2008年第四次国家卫生服务调查数据,将自报的家庭收入作为不能准确测量的潜变量,运用DIHOPIT模型确定反映家庭收入高低的指示变量,通过不同地区共同的指示变量,用相同或近似的指示变量作为截断点评价不同地区家庭收入的差别。用陕西省城乡6个县(区)的调查数据拟合模型,发现在众多的指示变量中,"电话类型"为5个县(区)共同指示变量,同时也发现部分指示变量在部分调查县(区)缺乏效度,需要在今后的调查问卷条目设计时做适当调整和补充。 相似文献
995.
Julian D. Taylor Arūnas P. Verbyla Colin Cavanagh Marcus Newberry 《Australian & New Zealand Journal of Statistics》2012,54(4):427-449
There is an emerging need to advance linear mixed model technology to include variable selection methods that can simultaneously choose and estimate important effects from a potentially large number of covariates. However, the complex nature of variable selection has made it difficult for it to be incorporated into mixed models. In this paper we extend the well known class of penalties and show that they can be integrated succinctly into a linear mixed model setting. Under mild conditions, the estimator obtained from this mixed model penalised likelihood is shown to be consistent and asymptotically normally distributed. A simulation study reveals that the extended family of penalties achieves varying degrees of estimator shrinkage depending on the value of one of its parameters. The simulation study also shows there is a link between the number of false positives detected and the number of true coefficients when using the same penalty. This new mixed model variable selection (MMVS) technology was applied to a complex wheat quality data set to determine significant quantitative trait loci (QTL). 相似文献
996.
《Journal of Statistical Computation and Simulation》2012,82(14):2903-2918
A Bayesian approach is proposed for coefficient estimation in the Tobit quantile regression model. The proposed approach is based on placing a g-prior distribution depends on the quantile level on the regression coefficients. The prior is generalized by introducing a ridge parameter to address important challenges that may arise with censored data, such as multicollinearity and overfitting problems. Then, a stochastic search variable selection approach is proposed for Tobit quantile regression model based on g-prior. An expression for the hyperparameter g is proposed to calibrate the modified g-prior with a ridge parameter to the corresponding g-prior. Some possible extensions of the proposed approach are discussed, including the continuous and binary responses in quantile regression. The methods are illustrated using several simulation studies and a microarray study. The simulation studies and the microarray study indicate that the proposed approach performs well. 相似文献
997.
998.
《Journal of Statistical Computation and Simulation》2012,82(3):597-610
We consider a linear regression model where there are group structures in covariates. The group LASSO has been proposed for group variable selections. Many nonconvex penalties such as smoothly clipped absolute deviation and minimax concave penalty were extended to group variable selection problems. The group coordinate descent (GCD) algorithm is used popularly for fitting these models. However, the GCD algorithms are hard to be applied to nonconvex group penalties due to computational complexity unless the design matrix is orthogonal. In this paper, we propose an efficient optimization algorithm for nonconvex group penalties by combining the concave convex procedure and the group LASSO algorithm. We also extend the proposed algorithm for generalized linear models. We evaluate numerical efficiency of the proposed algorithm compared to existing GCD algorithms through simulated data and real data sets. 相似文献
999.
A new method of modeling coronary artery calcium (CAC) is needed in order to properly understand the probability of onset and growth of CAC. CAC remains a controversial indicator of cardiovascular disease (CVD) risk, but this may be due to ill-equipped methods of specifying CAC during the analysis phase of studies reporting an analysis where CAC is the primary outcome. The modern method of two-part latent growth modeling may represent a strong alternative to the myriad of existing methods for modeling CAC. We provide a brief overview of existing methods of analysis used for CAC before introducing the general latent growth curve model, how it extends into a two-part (semicontinuous) growth model, and how the ubiquitous problem of missing data can be effectively handled. We then present an example of how to model CAC using this framework. We demonstrate that utilizing this type of modeling strategy can result in traditional predictors of CAC (e.g. age, gender, and high-density lipoprotein cholesterol), exerting a different impact on the two different, yet simultaneous, operationalizations of CAC. This method of analyzing CAC could inform future analyses of CAC and inform subsequent discussions about the nature of its potential to inform long-term CVD risk and heart events. 相似文献
1000.
《统计学通讯:理论与方法》2012,41(2):281-306
AbstractIn this paper, we obtain the exponential-type inequalities for maximal partial sums of negatively superadditive dependent (NSD) random variables, which extends the corresponding results for independent and negatively associated (NA) random variables. Using these inequalities, we further investigate the weak convergence of the M-estimators in the generalized linear model with NSD errors, which generalize and improve the corresponding results of the independent random errors to that of NSD random errors. 相似文献