全文获取类型
收费全文 | 7647篇 |
免费 | 119篇 |
国内免费 | 33篇 |
专业分类
管理学 | 323篇 |
民族学 | 27篇 |
人口学 | 149篇 |
丛书文集 | 234篇 |
理论方法论 | 110篇 |
综合类 | 1825篇 |
社会学 | 79篇 |
统计学 | 5052篇 |
出版年
2024年 | 5篇 |
2023年 | 30篇 |
2022年 | 64篇 |
2021年 | 62篇 |
2020年 | 118篇 |
2019年 | 212篇 |
2018年 | 241篇 |
2017年 | 490篇 |
2016年 | 157篇 |
2015年 | 179篇 |
2014年 | 260篇 |
2013年 | 2184篇 |
2012年 | 577篇 |
2011年 | 302篇 |
2010年 | 223篇 |
2009年 | 251篇 |
2008年 | 268篇 |
2007年 | 269篇 |
2006年 | 232篇 |
2005年 | 241篇 |
2004年 | 192篇 |
2003年 | 185篇 |
2002年 | 170篇 |
2001年 | 153篇 |
2000年 | 138篇 |
1999年 | 85篇 |
1998年 | 68篇 |
1997年 | 59篇 |
1996年 | 47篇 |
1995年 | 36篇 |
1994年 | 27篇 |
1993年 | 32篇 |
1992年 | 30篇 |
1991年 | 27篇 |
1990年 | 29篇 |
1989年 | 23篇 |
1988年 | 16篇 |
1987年 | 16篇 |
1986年 | 8篇 |
1985年 | 13篇 |
1984年 | 13篇 |
1983年 | 18篇 |
1982年 | 8篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1979年 | 9篇 |
1978年 | 8篇 |
1977年 | 6篇 |
1976年 | 4篇 |
1975年 | 5篇 |
排序方式: 共有7799条查询结果,搜索用时 12 毫秒
11.
CATIA SCRICCIOLO 《Scandinavian Journal of Statistics》2007,34(3):626-642
Abstract. We consider the problem of estimating a compactly supported density taking a Bayesian nonparametric approach. We define a Dirichlet mixture prior that, while selecting piecewise constant densities, has full support on the Hellinger metric space of all commonly dominated probability measures on a known bounded interval. We derive pointwise rates of convergence for the posterior expected density by studying the speed at which the posterior mass accumulates on shrinking Hellinger neighbourhoods of the sampling density. If the data are sampled from a strictly positive, α -Hölderian density, with α ∈ ( 0,1] , then the optimal convergence rate n− α / (2 α +1) is obtained up to a logarithmic factor. Smoothing histograms by polygons, a continuous piecewise linear estimator is obtained that for twice continuously differentiable, strictly positive densities satisfying boundary conditions attains a rate comparable up to a logarithmic factor to the convergence rate n −4/5 for integrated mean squared error of kernel type density estimators. 相似文献
12.
Abstract. The likelihood ratio statistic for testing pointwise hypotheses about the survival time distribution in the current status model can be inverted to yield confidence intervals (CIs). One advantage of this procedure is that CIs can be formed without estimating the unknown parameters that figure in the asymptotic distribution of the maximum likelihood estimator (MLE) of the distribution function. We discuss the likelihood ratio-based CIs for the distribution function and the quantile function and compare these intervals to several different intervals based on the MLE. The quantiles of the limiting distribution of the MLE are estimated using various methods including parametric fitting, kernel smoothing and subsampling techniques. Comparisons are carried out both for simulated data and on a data set involving time to immunization against rubella. The comparisons indicate that the likelihood ratio-based intervals are preferable from several perspectives. 相似文献
13.
David Oakes 《Revue canadienne de statistique》2005,33(3):465-468
The author characterizes the copula associated with the bivariate survival model of Clayton (1978) as the only absolutely continuous copula that is preserved under bivariate truncation. 相似文献
14.
Generalized Leverage and its Applications 总被引:2,自引:0,他引:2
The generalized leverage of an estimator is defined in regression models as a measure of the importance of individual observations. We derive a simple but powerful result, developing an explicit expression for leverage in a general M -estimation problem, of which the maximum likelihood problems are special cases. A variety of applications are considered, most notably to the exponential family non-linear models. The relationship between leverage and local influence is also discussed. Numerical examples are given to illustrate our results 相似文献
15.
A Multivariate Model for Repeated Failure Time Measurements 总被引:1,自引:1,他引:0
Martin Crowder 《Scandinavian Journal of Statistics》1998,25(1):53-67
A parametric multivariate failure time distribution is derived from a frailty-type model with a particular frailty distribution. It covers as special cases certain distributions which have been used for multivariate survival data in recent years. Some properties of the distribution are derived: its marginal and conditional distributions lie within the parametric family, and association between the component variates can be positive or, to a limited extent, negative. The simple closed form of the survivor function is useful for right-censored data, as occur commonly in survival analysis, and for calculating uniform residuals. Also featured is the distribution of ratios of paired failure times. The model is applied to data from the literature 相似文献
16.
Approximation of a density by another density is considered in the case of different dimensionalities of the distributions. The results have been derived by inverting expansions of characteristic functions with the help of matrix techniques. The approximations obtained are all functions of cumulant differences and derivatives of the approximating density. The multivariate Edgeworth expansion follows from the results as a special case. Furthermore, the density functions of the trace and eigenvalues of the sample covariance matrix are approximated by the multivariate normal density and a numerical example is given 相似文献
17.
A K -sample testing problem is studied for multivariate counting processes with time-dependent frailty. Asymptotic distributions and efficiency of a class of non-parametric test statistics are established for certain local alternatives. The concept of efficiency is to show that for every non-parametric test in this class, there is a parametric submodel for which the optimal test has the same asymptotic power as the non-parametric one. The theory is applied to analyse a diabetic retinopathy study data set. A simulation study is also presented to illustrate the theory 相似文献
18.
LetX1,X2, ..., be real-valued random variables forming a strictly stationary sequence, and satisfying the basic requirement of being either pairwise positively quadrant dependent or pairwise negatively quadrant dependent. LetF^ be the marginal distribution function of theXips, which is estimated by the empirical distribution functionFn and also by a smooth kernel-type estimateFn, by means of the segmentX1, ...,Xn. These estimates are compared on the basis of their mean squared errors (MSE). The main results of this paper are the following. Under certain regularity conditions, the optimal bandwidth (in the MSE sense) is determined, and is found to be the same as that in the independent identically distributed case. It is also shown thatn MSE(Fn(t)) andnMSE (F^n(t)) tend to the same constant, asn→∞ so that one can not discriminate be tween the two estimates on the basis of the MSE. Next, ifi(n) = min {k∈{1, 2, ...}; MSE (Fk(t)) ≤ MSE (Fn(t))}, then it is proved thati(n)/n tends to 1, asn→∞. Thus, once again, one can not choose one estimate over the other in terms of their asymptotic relative efficiency. If, however, the squared bias ofF^n(t) tends to 0 sufficiently fast, or equivalently, the bandwidthhn satisfies the requirement thatnh3n→ 0, asn→∞, it is shown that, for a suitable choice of the kernel, (i(n) ?n)/(nhn) tends to a positive number, asn→∞ It follows that the deficiency ofFn(t) with respect toF^n(t),i(n) ?n, is substantial, and, actually, tends to ∞, asn→∞. In terms of deficiency, the smooth estimateF^n(t) is preferable to the empirical distribution functionFn(t) 相似文献
19.
The posterior distribution of the likelihood is used to interpret the evidential meaning of P-values, posterior Bayes factors and Akaike's information criterion when comparing point null hypotheses with composite alternatives. Asymptotic arguments lead to simple re-calibrations of these criteria in terms of posterior tail probabilities of the likelihood ratio. (Prior) Bayes factors cannot be calibrated in this way as they are model-specific. 相似文献
20.
This paper examines recent changes in weekly income levels and dispersion for Māori, New Zealand’s indigenous ethnic group.
Changes in the Māori income distribution between 1997 and 2003 reflect rapid increases in economic growth and employment rate.
A reduced proportion of people had zero or benefit-level incomes and a higher proportion had high incomes. Income inequality
declined for working-aged Māori and was stable for employed Māori. The average income gap between Māori and Europeans declined.
The increased Māori employment rate during this period was the single most important driver of changes in the Māori income
distribution.
相似文献
David C. Maré (Corresponding author)Email: |