全文获取类型
收费全文 | 426篇 |
免费 | 33篇 |
国内免费 | 54篇 |
专业分类
化学 | 3篇 |
力学 | 5篇 |
综合类 | 5篇 |
数学 | 494篇 |
物理学 | 6篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 11篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 16篇 |
2016年 | 10篇 |
2015年 | 4篇 |
2014年 | 21篇 |
2013年 | 31篇 |
2012年 | 12篇 |
2011年 | 15篇 |
2010年 | 21篇 |
2009年 | 25篇 |
2008年 | 31篇 |
2007年 | 31篇 |
2006年 | 32篇 |
2005年 | 29篇 |
2004年 | 15篇 |
2003年 | 21篇 |
2002年 | 19篇 |
2001年 | 9篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 13篇 |
1997年 | 13篇 |
1996年 | 11篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 9篇 |
1990年 | 9篇 |
1989年 | 4篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 4篇 |
1985年 | 6篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1979年 | 4篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1973年 | 2篇 |
1959年 | 1篇 |
排序方式: 共有513条查询结果,搜索用时 62 毫秒
101.
计算机仿真模型广泛应用于工业工程等领域,借助真实的物理观测对计算机模型的校准参数进行估计,可以提高计算机模型的仿真精度.已有文献指出,当物理试验的试验点独立同分布于均匀分布时,计算机模型校准参数的L2估计半参数有效.然而真实的物理试验点往往不满足独立同分布于均匀分布这一条件,文章证明了在固定的试验点下,较准参数L2估计的相合性和渐近正态性,并通过数值模拟验证了L2估计的收敛速度. 相似文献
102.
Alan F. Karr 《Journal of multivariate analysis》1985,16(3):368-392
Given i.i.d. point processes N1, N2,…, let the observations be p-thinnings N′1, N′2,…, where p is a function from the underlying space E (a compact metric space) to [0, 1], whose interpretation is that a point of Ni at x is retained with probability p(x) and deleted with probability 1−p(x). Strongly consistent estimators of the thinning function p and the Laplace functional LN(f) = E[e−N(f)] of the Ni are constructed; associated “central limit” properties are given. Tests are presented, for the case when the Ni and N′i are both observable, of the hypothesis that the N′i are p-thinnings of the Ni. State estimation techniques are developed for the case where the Ni are Cox processes directed by unobservable random measures Mi; these techniques yield minimum mean-squared error estimators, based on observation of only the thinned processes N′i of the Ni and the directing measures Mi. Limit theorems for empirical Laplace functionals of point processes are given. 相似文献
103.
Qi-Hua Wang 《Annals of the Institute of Statistical Mathematics》2003,55(1):21-39
In this paper, an estimation theory in partial linear model is developed when there is measurement error in the response and
when validation data are available. A semiparametric method with the primary data is used to define two estimators for both
the regression parameter and the nonparametric part using the least squares criterion with the help of validation data. The
proposed estimators of the parameter are proved to be strongly consistent and asymptotically normaal, and the estimators of
the nonparametric part are also proved to be strongly consistent and weakly consistent with an optimal convergent rate. Then,
the two estimators of the parameter are compared based on their empirical performances.
Supported by NNSF of China (No. 10231030, No. 10241001) and a grant to the author for his excellent Ph.D. dissertation work
in China. 相似文献
104.
S. Lototsky 《Statistical Inference for Stochastic Processes》2003,6(1):65-87
A two-dimensional parameter is estimated from the observations of a random field defined on a compact manifold by a stochastic parabolic equation. Unlike the previous works on the subject, the equation is not necessarily diagonalizable, and no assumptions are made about the eigenfunctions of the operators in the equation. The estimator is based on certain finite-dimensional projections of the observed random field, and the asymptotic properties of the estimator are studied as the dimension of the projection is increased while the observation time is fixed. Simple conditions are found for the consistency and asymptotic normality of the estimator. An application to a problem in oceanography is discussed. 相似文献
105.
广义线性回归拟似然估计的渐近正态性 总被引:7,自引:0,他引:7
研究了形如n∑i=1xi(yi-μ(xi′β))=0拟似然方程,在一定的条件下证明了拟似然估计βn的渐近正态性;并进一步证明了可用于β0大样本统计推断的渐近正态性结果. 相似文献
106.
本文研究了下列变系数混合效应模型: $y_{ij}=z_{ij}^{\tau}b_i+x_{ij}^{\tau}\beta(w_{ij}) +\xe_{ij},\;i=1,\cdots,m;\;j=1,\cdots,n_i$, 其中$b_i$为i.i.d.期望为$\xt$, 协方差阵为$\xs^2_bI_q$的随机效应向量, $\xe_{ij}$是i.i.d.期望为零, 具有有限方差的随机误差. 文中我们不仅给出了函数系数向量$\xb(\cdot)$的局部多项式估计, 同时给出了随机效应期望、方差和随机误差方差的估计, 并给出了这些估计量的渐进正态性和相合性, 研究结果表明了这些估计量的可靠性. 相似文献
107.
108.
Consider a simple branching diffusion process, which is a branching process in which the individuals move and live and die in space. The offspring distribution has finite moments of all orders. A parametric estimation theory is presented, using time slice data. This involves the use of third order cumulant spectra to identify and estimate the parameters. 相似文献
109.
Ingrid Van Keilegom Noël Veraverbeke 《Annals of the Institute of Statistical Mathematics》1997,49(3):467-491
We study Beran's extension of the Kaplan-Meier estimator for thesituation of right censored observations at fixed covariate values. Thisestimator for the conditional distribution function at a given value of thecovariate involves smoothing with Gasser-Müller weights. We establishan almost sure asymptotic representation which provides a key tool forobtaining central limit results. To avoid complicated estimation ofasymptotic bias and variance parameters, we propose a resampling methodwhich takes the covariate information into account. An asymptoticrepresentation for the bootstrapped estimator is proved and the strongconsistency of the bootstrap approximation to the conditional distributionfunction is obtained. 相似文献
110.
Frank Marohn 《Extremes》1998,1(2):191-213
We consider an i.i.d. sample, generated by some distribution function, which belongs to the domain of attraction of an extreme value distribution with unknown shape and scale parameters. We treat the scale parameter as a nuisance parameter and establish for the hypothesis of Gumbel domain of attraction an asymptotically optimal test based on those observations among the sample, which exceed a given threshold sequence. Asymptotic optimality is achieved along certain contiguous extreme value alternatives within the concept of local asymptotic normality (LAN). Adaptive test procedures exist under restrictive assumptions. The finite sample size behavior of the proposed test is studied by simulations and it is compared to that of a test based on the sample coefficient of variation. 相似文献