首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8359篇
  免费   161篇
  国内免费   63篇
管理学   361篇
劳动科学   2篇
民族学   74篇
人才学   1篇
人口学   55篇
丛书文集   743篇
理论方法论   180篇
综合类   4602篇
社会学   110篇
统计学   2455篇
  2024年   4篇
  2023年   23篇
  2022年   31篇
  2021年   59篇
  2020年   86篇
  2019年   103篇
  2018年   128篇
  2017年   231篇
  2016年   132篇
  2015年   167篇
  2014年   297篇
  2013年   1168篇
  2012年   475篇
  2011年   434篇
  2010年   402篇
  2009年   416篇
  2008年   460篇
  2007年   553篇
  2006年   527篇
  2005年   506篇
  2004年   437篇
  2003年   437篇
  2002年   351篇
  2001年   333篇
  2000年   204篇
  1999年   88篇
  1998年   80篇
  1997年   60篇
  1996年   53篇
  1995年   74篇
  1994年   50篇
  1993年   40篇
  1992年   37篇
  1991年   21篇
  1990年   15篇
  1989年   27篇
  1988年   16篇
  1987年   14篇
  1986年   4篇
  1985年   5篇
  1984年   11篇
  1983年   9篇
  1982年   3篇
  1981年   4篇
  1980年   2篇
  1979年   1篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1966年   1篇
排序方式: 共有8583条查询结果,搜索用时 16 毫秒
51.
This article investigates an efficient estimation method for a class of switching regressions based on the characteristic function (CF). We show that with the exponential weighting function, the CF-based estimator can be achieved from minimizing a closed form distance measure. Due to the availability of the analytical structure of the asymptotic covariance, an iterative estimation procedure is developed involving the minimization of a precision measure of the asymptotic covariance matrix. Numerical examples are illustrated via a set of Monte Carlo experiments examining the implementation, finite sample property and the efficiency of the proposed estimator.  相似文献   
52.
53.
This article reports on work designed to measure the time required for a change in a stock's price to be fully reflected in the price of a warrant on that stock. The method employed to measure the adjustment speed is the bivariate transfer function technique of Box and Jenkins. An interesting aspect of the study is the use of trade-by-trade data for measuring stock and warrant returns. The evidence presented here suggests that warrant prices adjust quickly to changes in stock prices. In addition, evidence concerning the ability of the estimated models to forecast warrant prices is presented.  相似文献   
54.
The comparative powers of six discrete goodness-of-fit test statistics for a uniform null distribution against a variety of fully specified alternative distributions are discussed. The results suggest that the test statistics based on the empirical distribution function for ordinal data (Kolmogorov–Smirnov, Cramér–von Mises, and Anderson–Darling) are generally more powerful for trend alternative distributions. The test statistics for nominal (Pearson's chi-square and the nominal Kolmogorov–Smirnov) and circular data (Watson's test statistic) are shown to be generally more powerful for the investigated triangular (∨), flat (or platykurtic type), sharp (or leptokurtic type), and bimodal alternative distributions.  相似文献   
55.
In this article, we discuss some properties of Renyi entropy and Renyi information of order statistics. Some bounds for Renyi entropy of order statistics are obtained. Also, we relate Renyi entropy ordering of order statistics to Renyi entropy ordering and other well known orderings of parent random variables. Then it is proved that the Renyi information between order statistics and parent random variable is distribution free, and it is shown, as expected, the distance is minimum for the median.  相似文献   
56.
In this article, we establish optimal rates for the strong approximation of empirical copula processes in ?2 by sequences of Gaussian processes. These results are applied to investigate Cramér–von Mises-type statistics.  相似文献   
57.
In most reliability studies involving censoring, one assumes that censoring probabilities are unknown. We derive a nonparametric estimator for the survival function when information regarding censoring frequency is available. The estimator is constructed by adjusting the Nelson–Aalen estimator to incorporate censoring information. Our results indicate significant improvements can be achieved if available information regarding censoring is used. We compare this model to the Koziol–Green model, which is also based on a form of proportional hazards for the lifetime and censoring distributions. Two examples of survival data help to illustrate the differences in the estimation techniques.  相似文献   
58.
This article considers the properties of a nonparametric estimator developed for a reliability function which is used in many reliability problems. Properties such as asymptotic unbiasedness and consistency are proven for the estimator and using U-statistics, weak convergence of the estimator to a normal distribution is shown. Finally, numerical examples based on an extensive simulation study are presented to illustrate the theory and compare the estimator developed in this article with another based directly on the ratio of two empirical distributions studied in Zardasht and Asadi (2010 Zardasht , V. , Asadi , M. ( 2010 ). Evaluation of P(X t  > Y t ) when both X t and Y t are residual lifetimes of two systems . Statistica Neerlandica 64 : 460481 .[Crossref], [Web of Science ®] [Google Scholar]).  相似文献   
59.
In this work we investigate nonnested tests for two competing univariate dynamic linear models with autoregressive disturbances, where the motivation for instrumental variable estimation is mainly due to the recognized presence of current endogenous variables in the regression function, either in one or both models. As the previous transformation of both models yields regression functions which are nonlinear in the parameters, the attractive Gauss-Newton regression (GNR) approach, firstly advocated by Davidson and Mackinnon (1981 Davidson , R. , Mackinnon , J. G. ( 1981 ). Several tests for model specification in the presence of alternative hypotheses . Econometrica 49 : 78193 .[Crossref], [Web of Science ®] [Google Scholar]), will be used to obtain the results.  相似文献   
60.
The Lomax (Pareto II) distribution has found wide application in a variety of fields. We analyze the second-order bias of the maximum likelihood estimators of its parameters for finite sample sizes, and show that this bias is positive. We derive an analytic bias correction which reduces the percentage bias of these estimators by one or two orders of magnitude, while simultaneously reducing relative mean squared error. Our simulations show that this performance is very similar to that of a parametric bootstrap correction based on a linear bias function. Three examples with actual data illustrate the application of our bias correction.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号