全文获取类型
收费全文 | 7726篇 |
免费 | 227篇 |
国内免费 | 81篇 |
专业分类
管理学 | 170篇 |
劳动科学 | 2篇 |
民族学 | 47篇 |
人才学 | 1篇 |
人口学 | 189篇 |
丛书文集 | 724篇 |
理论方法论 | 477篇 |
综合类 | 3961篇 |
社会学 | 886篇 |
统计学 | 1577篇 |
出版年
2024年 | 13篇 |
2023年 | 64篇 |
2022年 | 68篇 |
2021年 | 104篇 |
2020年 | 154篇 |
2019年 | 204篇 |
2018年 | 206篇 |
2017年 | 261篇 |
2016年 | 183篇 |
2015年 | 255篇 |
2014年 | 835篇 |
2013年 | 1454篇 |
2012年 | 944篇 |
2011年 | 627篇 |
2010年 | 628篇 |
2009年 | 499篇 |
2008年 | 429篇 |
2007年 | 136篇 |
2006年 | 102篇 |
2005年 | 117篇 |
2004年 | 122篇 |
2003年 | 138篇 |
2002年 | 126篇 |
2001年 | 74篇 |
2000年 | 56篇 |
1999年 | 31篇 |
1998年 | 24篇 |
1997年 | 21篇 |
1996年 | 17篇 |
1995年 | 16篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 10篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 1篇 |
1986年 | 5篇 |
1985年 | 8篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 12篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 1篇 |
排序方式: 共有8034条查询结果,搜索用时 15 毫秒
51.
We consider nonlinear and heteroscedastic autoregressive models whose residuals are martingale increments with conditional distributions that fulfil certain constraints. We treat two classes of constraints: residuals depending on the past through some function of the past observations only, and residuals that are invariant under some finite group of transformations. We determine the efficient influence function for estimators of the autoregressive parameter in such models, calculate variance bounds, discuss information gains, and suggest how to construct efficient estimators. Without constraints, efficient estimators can be given by weighted least squares estimators. With the constraints considered here, efficient estimators are obtained differently, as one-step improvements of some initial estimator, similarly as in autoregressive models with independent increments. 相似文献
52.
We study distributional properties of generalized order statistics (gos) related by a random shift or scaling scheme in the continuous and discrete case, respectively. In the continuous case, we obtain new characterizations of distributions relating non-neighbouring gos extending some results given in the literature for the neighbouring cases. On the other hand, in the discrete case, we investigate the existence and uniqueness of a discrete parent distribution supported on the integers whose gos are related by a random translation. 相似文献
53.
Orthogonal block designs in mixture experiments have been extensively studied by various authors. Aggarwal et al. [M.L. Aggarwal, P. Singh, V. Sarin, and B. Husain, Mixture designs in orthogonal blocks using F-squares, METRON – Int. J. Statist. LXVII(2) (2009), pp. 105–128] considered the case of components assuming the same volume fractions and obtained mixture designs in orthogonal blocks using F-squares. In this paper, we have used the class of designs presented by Aggarwal et al. and have obtained D-, A- and E-optimal orthogonal block designs for four components in two blocks for Becker's mixture models and K-model, respectively. Orthogonality conditions for the considered models are also given. 相似文献
54.
Vassili Blandin 《Statistics》2013,47(6):1202-1232
The purpose of this paper is to study the asymptotic behaviour of the weighted least-squares estimators of the unknown parameters of random coefficient bifurcating autoregressive processes. Under suitable assumptions on the immigration and the inheritance, we establish the almost sure convergence of our estimators, as well as a quadratic strong law and central limit theorems. Our study mostly relies on limit theorems for vector-valued martingales. 相似文献
55.
Dankmar Böhing 《Statistics》2013,47(4):487-495
Tn optimal experimental design theory there are well-known situations, in which additional constraints are implied to the design set. These constraints destroy in general the simplex structure of the set of feasible points of the design set. Thus the available iteration procedures for the unrestricted case are no longer applicable. In this paper a penalty approach is suggested which transforms the restricted problem to the unrestricted case and allows the application of well-known algorithms such as the Fedorov-Wynn-type or the projected gradient procedure. 相似文献
56.
Alireza Ghodsi 《统计学通讯:模拟与计算》2013,42(6):1256-1268
In this article, we implement the Regression Method for estimating (d 1, d 2) of the FISSAR(1, 1) model. It is also possible to estimate d 1 and d 2 by Whittle's method. We also compute the estimated bias, standard error, and root mean square error by a simulation study. A comparison was made between the Regression Method of estimating d 1 and d 2 to that of the Whittle's method. It was found in this simulation study that the Regression Method of estimation was better when compare with the Whittle's estimator, in the sense that it had smaller root mean square errors (RMSE) values. 相似文献
57.
This article is devoted to the study of the periodicity testing problem in a self-exciting threshold autoregressive (SETAR) model. The local asymptotic normality (LAN) property is shown via the adapted sufficient conditions due to Swensen (1985). Moreover, the LAN of the central sequence is established. First, we consider the case where the innovation density is specified and we obtain a parametric local asymptotic test. Second, we construct an adaptive test in the case where this density is unspecified but symmetric. The performances of these established tests are shown via simulation studies. 相似文献
58.
Finding the influence of traffic accident on the road is helpful to analyze the characteristics of traffic flow, and take reasonable and effective control measures. Here, the detrended fluctuation analysis method is applied to investigate the complexity of time series in mixed traffic flow with a blockage induced by an accident. As a parameter to depict the long-term evolutionary behavior of the time series in traffic flow, the scaling exponent is analyzed. According to the scaling exponent, it is shown that the traffic flow time series can display long-range correlation characteristics, short-range correlation characteristics, and non-power-law relation in the long-range correlation characteristics, which is strongly dependent on the entering probability of vehicle, the ratio of slow vehicle and the blockage duration time. 相似文献
59.
Jing Wang 《统计学通讯:模拟与计算》2013,42(3):539-556
In this article, we use two efficient approaches to deal with the difficulty in computing the intractable integrals when implementing Gibbs sampling in the nonlinear mixed effects model (NLMM) based on Dirichlet processes (DP). In the first approach, we compute the Laplace's approximation to the integral for its high accuracy, low cost, and ease of implementation. The second approach uses the no-gaps algorithm of MacEachern and Müller (1998) to perform Gibbs sampling without evaluating the difficult integral. We apply both approaches to real problems and simulations. Results show that both approaches perform well in density estimation and prediction and are superior to the parametric analysis in that they can detect important model features, such as skewness, long tails, and multimodality, whereas the parametric analysis cannot. 相似文献
60.
A simple approximation for the doubly noncentral t-distribution, based upon the Fieller-Geary Theorem (1930) and approximate normality of the square root of the noncentral chi-square variable observed by Patnaik (1949), is developed, This approximation and an Edgeworth series expansion associated with it are evaluated. The simple approximation is seen to be reasonably accurate for most practical purposes. 相似文献