全文获取类型
收费全文 | 1502篇 |
免费 | 31篇 |
国内免费 | 5篇 |
专业分类
管理学 | 154篇 |
民族学 | 2篇 |
人口学 | 19篇 |
丛书文集 | 55篇 |
理论方法论 | 23篇 |
综合类 | 334篇 |
社会学 | 31篇 |
统计学 | 920篇 |
出版年
2023年 | 7篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 13篇 |
2019年 | 37篇 |
2018年 | 46篇 |
2017年 | 83篇 |
2016年 | 26篇 |
2015年 | 33篇 |
2014年 | 38篇 |
2013年 | 400篇 |
2012年 | 97篇 |
2011年 | 59篇 |
2010年 | 56篇 |
2009年 | 55篇 |
2008年 | 57篇 |
2007年 | 57篇 |
2006年 | 58篇 |
2005年 | 46篇 |
2004年 | 43篇 |
2003年 | 44篇 |
2002年 | 25篇 |
2001年 | 32篇 |
2000年 | 13篇 |
1999年 | 16篇 |
1998年 | 13篇 |
1997年 | 13篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 9篇 |
1991年 | 13篇 |
1990年 | 11篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1985年 | 11篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 14篇 |
1981年 | 12篇 |
1980年 | 5篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有1538条查询结果,搜索用时 31 毫秒
11.
This study examines the relationships among personal coping resources, social support, external coping resources, job stressors and job strains in a sample of 110 American Telephone and Telegraph employees undergoing a major organizational restructuring. The study expanded on a model suggested by Ashford (1988) by defining another category of coping resources that employees may draw upon to deal with the stressors and strains which occur during major organizational changes. External coping resources were defined as those which provided employees with a sense of 'vicarious control' in stressful situations. Results indicated that personal coping resources, social support and external coping resources had a direct effect upon job stressor and strain levels. No 'buffering' effect of these coplng resources was found. Hierarchical regression analyses indicated that external coping resources added to the prediction of job stressors and strains even when pertonal coping resources and social support were entered first into the prediction questions. 相似文献
12.
Summary This paper solves some D-optimal design problems for certain Generalized Linear Models where the mean depends on two parameters
and two explanatory variables. In all of the cases considered the support point of the optimal designs are found to be independent
of the unknown parameters. While in some cases the optimal design measures are given by two points with equal weights, in
others the support is given by three point with weights depending on the unknown parameters, hence the designs are locally
optimal in general. Empirical results on the efficiency of the locally optimal designs are also given. Some of the designs
found can also be used for planning D-optimal experiments for the normal linear model, where the mean must be positive.
This research was carried out in part at University College, London as an M.Sc. project. Thanks are due to Prof. I. Ford (University
of Glasgow) and Prof. A. Giovagnoli (University of Perugia) for their valuable suggestions and critical observations. 相似文献
13.
Zhang Xueyuan 《湖南文理学院学报(社会科学版)》1996,(6)
本文对系数全为多项式和广义多项式的n阶线性齐次微分方程引入特征方程的概念。给出了具有指数型解的充要条件,推广了经典的常系数线性方程和著名的Euler方程的的解法,为求解变系数线性微分方程提供了有效的方法。 相似文献
14.
汤光宋 《济南大学学报(社会科学版)》1998,(1)
给出二维变系数线性微分系统在已知某解的情形下求通解的公式,并直接应用此公式,导出几类二维变系数线性微分系统的通解公式.对理论和实际应用都是有益的. 相似文献
15.
本文讨论了一类完全竞争条件下的市场均衡问题,供给方的生产特征用线性规划模型进行刻划,市场需求函数源于一般经济意义下的模型,它是一系列相互独立的价格变量的函数.我们将此问题归结为线性互补问题,并依此讨论了均衡点的存在性.本文还讨论了一种用二次规划进行刻划的经济问题,并指出此二次规划的K-K-T条件等价于所讨论的线性互补问题. 相似文献
16.
《Journal of Statistical Computation and Simulation》2012,82(4):415-426
This paper considers the problem where the linear discriminant rule is formed from training data that are only partially classified with respect to the two groups of origin. A further complication is that the data of unknown origin do not constitute an observed random sample from a mixture of the two under- lying groups. Under the assumption of a homoscedastic normal model, the overall error rate of the sample linear discriminant rule formed by maximum likelihood from the partially classified training data is derived up to and including terms of the first order in the case of univariate feature data. This first- order expansion of the sample rule so formed is used to define its asymptotic efficiency relative to the rule formed from a completely classified random training set and also to the rule formed from a completely unclassified random set. 相似文献
17.
《Journal of Statistical Computation and Simulation》2012,82(11):863-879
The finite sample performance of a number of tests for symmetry of the distribution of the errors of a linear model is considered. The first family of tests is based on the discrepancy between two regression fits. The first fit is appropriate under symmetric errors while the second is appropriate for skewed as well as symmetric error distributions. The second family of procedures consists of tests for the univariate symmetry problem. Thus, in the linear model setting these tests are based on residuals. An extensive empirical study of the finite sample, null behavior of the tests is presented. The results of a power comparison among the tests is also discussed. 相似文献
18.
《Journal of Statistical Computation and Simulation》2012,82(2-3):91-104
The coverage rate of the original data by the prediction interval in simple linear regression is obtained by computer simulation. The results show that for small sample size, the coverage rate is higher than the assigned prediction coverage rate (confidence level). The two coverage rates begin to converge when the sample size is larger than 50 and the convergence rate depends very little on the distribution of the independent variable. Also, theoretical results on the asymptotic coverage rate and on the absolute minimum bounds are obtained 相似文献
19.
《The American statistician》2012,66(4):321-326
ABSTRACTA statistical test can be seen as a procedure to produce a decision based on observed data, where some decisions consist of rejecting a hypothesis (yielding a significant result) and some do not, and where one controls the probability to make a wrong rejection at some prespecified significance level. Whereas traditional hypothesis testing involves only two possible decisions (to reject or not a null hypothesis), Kaiser’s directional two-sided test as well as the more recently introduced testing procedure of Jones and Tukey, each equivalent to running two one-sided tests, involve three possible decisions to infer the value of a unidimensional parameter. The latter procedure assumes that a point null hypothesis is impossible (e.g., that two treatments cannot have exactly the same effect), allowing a gain of statistical power. There are, however, situations where a point hypothesis is indeed plausible, for example, when considering hypotheses derived from Einstein’s theories. In this article, we introduce a five-decision rule testing procedure, equivalent to running a traditional two-sided test in addition to two one-sided tests, which combines the advantages of the testing procedures of Kaiser (no assumption on a point hypothesis being impossible) and Jones and Tukey (higher power), allowing for a nonnegligible (typically 20%) reduction of the sample size needed to reach a given statistical power to get a significant result, compared to the traditional approach. 相似文献
20.
本文将最小二乘支持向量机(LSSVM) 和二次推断函数法(QIF) 相结合,为个体内具有相关结构的固定效应部分线性变系数面板模型提供了一种新的快速估计方法;在一定的正则条件下,论证了参数估计量的渐近正态性和非参数估计量的收敛速度;采用Monte Carlo模拟考察了估计方法在有限样本下的表现并将估计技术应用于现实数据分析。该方法不仅保证了估计的有效性和统计推断力,而且程序运行速度得到较大幅度提升。 相似文献