全文获取类型
收费全文 | 1334篇 |
免费 | 32篇 |
国内免费 | 13篇 |
专业分类
管理学 | 74篇 |
民族学 | 6篇 |
人口学 | 10篇 |
丛书文集 | 97篇 |
理论方法论 | 14篇 |
综合类 | 859篇 |
社会学 | 34篇 |
统计学 | 285篇 |
出版年
2023年 | 4篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 15篇 |
2019年 | 20篇 |
2018年 | 23篇 |
2017年 | 33篇 |
2016年 | 23篇 |
2015年 | 31篇 |
2014年 | 45篇 |
2013年 | 133篇 |
2012年 | 83篇 |
2011年 | 57篇 |
2010年 | 67篇 |
2009年 | 60篇 |
2008年 | 73篇 |
2007年 | 90篇 |
2006年 | 119篇 |
2005年 | 85篇 |
2004年 | 62篇 |
2003年 | 76篇 |
2002年 | 60篇 |
2001年 | 50篇 |
2000年 | 42篇 |
1999年 | 18篇 |
1998年 | 16篇 |
1997年 | 15篇 |
1996年 | 15篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 2篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有1379条查询结果,搜索用时 15 毫秒
21.
军机备件需求量修正的粗糙集方法 总被引:2,自引:0,他引:2
本文针对不可量化因素对军机备件需求量的影响,提出了基于粗糙集的备件需求量的修正方法。考虑不可量化因素存在多值性的问题,将不可分辨关系下的经典粗糙集方法拓展成相容关系下的扩展粗糙集方法,通过相容关系下的近似空间获取决策规则,再由决策规则得到修正系数。最后以轮胎类器材为例,说明了修正系数的获取过程。 相似文献
22.
23.
The paper presents a general method of designing constant-factor approximation algorithms for some discrete optimization problems with assignment-type constraints. The core of the method is a simple deterministic procedure of rounding of linear relaxations (referred to as pipage rounding). With the help of the method we design approximation algorithms with better performance guarantees for some well-known problems including MAXIMUM COVERAGE, MAX CUT with given sizes of parts and some of their generalizations. 相似文献
24.
中国股市收益率分布特征研究 总被引:7,自引:3,他引:7
应用修正Weibull分布对上海综合指数收益率和深圳成分指数收益率的分布状况进行研究。结果表明:经过简单的移位变换后,上证综指收益率和深成指收益率可完全用修正Weibull分布来刻画;大收益率服从次指数分布,小收益率服从超指数分布;两股指收益率的概率分布存在一些差异,上证综指的波动性大于深成指的波动性;沪深股市收益率的分布在1996年以后发生了较大的变化,其中沪市变化更大。 相似文献
25.
Nilgun Ozgul 《统计学通讯:理论与方法》2019,48(6):1481-1492
In recent years, calibration estimation has become an important field of research in survey sampling. This paper proposes a new calibration estimator for the population mean in the presence of two auxiliary variables in stratified sampling. The theory of new calibration estimator is given and optimum calibration weights are derived. A simulation study is carried out to performance of the proposed calibration estimator over other existing calibration estimators. The results reveal that the proposed calibration estimators are more efficient than other existing calibration estimators in stratified sampling. 相似文献
26.
27.
《Journal of Statistical Computation and Simulation》2012,82(10):2233-2247
In this paper, we develop modified versions of the likelihood ratio test for multivariate heteroskedastic errors-in-variables regression models. The error terms are allowed to follow a multivariate distribution in the elliptical class of distributions, which has the normal distribution as a special case. We derive the Skovgaard-adjusted likelihood ratio statistics, which follow a chi-squared distribution with a high degree of accuracy. We conduct a simulation study and show that the proposed tests display superior finite sample behaviour as compared to the standard likelihood ratio test. We illustrate the usefulness of our results in applied settings using a data set from the WHO MONICA Project on cardiovascular disease. 相似文献
28.
《Journal of Statistical Computation and Simulation》2012,82(10):1869-1890
ABSTRACTWe consider the use of modern likelihood asymptotics in the construction of confidence intervals for the parameter which determines the skewness of the distribution of the maximum/minimum of an exchangeable bivariate normal random vector. Simulation studies were conducted to investigate the accuracy of the proposed methods and to compare them to available alternatives. Accuracy is evaluated in terms of both coverage probability and expected length of the interval. We furthermore illustrate the suitability of our proposals by means of two data sets, consisting of, respectively, measurements taken on the brains of 10 mono-zygotic twins and measurements of mineral content of bones in the dominant and non-dominant arms for 25 elderly women. 相似文献
29.
Aylin Göçoğlu 《Journal of Statistical Computation and Simulation》2019,89(14):2694-2710
In this paper, proportion estimators and associated variance estimators are proposed for a binary variable with a concomitant variable based on modified ranked set sampling methods, which are extreme ranked set sampling (ERSS), median ranked set sampling (MRSS), percentile ranked set sampling (Per-RSS) and L ranked set sampling (LRSS) methods. The Monte Carlo simulation study is performed to compare the performance of the estimators based on bias, mean squared error, and relative efficiency for different levels of correlation coefficient, set and cycle sizes under normal and log-normal distributions. Moreover, the study is supported with real data application. 相似文献
30.
Adrianna Kezar 《International Journal of Social Research Methodology》2016,19(2):143-160
In this article, we describe ways that the Delphi technique can be extended from its more traditional approaches and processes in order to make it a tool for scholars using participatory methods. This innovative proposed approach is called the change-oriented Delphi. We describe this innovative approach using an example from our own work to create solutions to the growth of non-tenure-track faculty in higher education institutions, which is negatively impacting student outcomes. 相似文献