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   2333篇
  免费   74篇
管理学   314篇
民族学   18篇
人口学   225篇
丛书文集   19篇
理论方法论   213篇
综合类   134篇
社会学   1215篇
统计学   269篇
  2023年   31篇
  2022年   21篇
  2021年   30篇
  2020年   76篇
  2019年   94篇
  2018年   107篇
  2017年   154篇
  2016年   111篇
  2015年   65篇
  2014年   96篇
  2013年   317篇
  2012年   239篇
  2011年   105篇
  2010年   83篇
  2009年   61篇
  2008年   66篇
  2007年   70篇
  2006年   59篇
  2005年   60篇
  2004年   105篇
  2003年   100篇
  2002年   74篇
  2001年   49篇
  2000年   37篇
  1999年   12篇
  1998年   8篇
  1997年   6篇
  1996年   16篇
  1995年   6篇
  1994年   13篇
  1993年   6篇
  1992年   17篇
  1991年   11篇
  1990年   9篇
  1989年   9篇
  1988年   6篇
  1987年   9篇
  1985年   3篇
  1984年   5篇
  1983年   6篇
  1982年   6篇
  1981年   8篇
  1980年   7篇
  1979年   3篇
  1978年   5篇
  1975年   2篇
  1974年   5篇
  1970年   2篇
  1967年   2篇
  1966年   2篇
排序方式: 共有2407条查询结果,搜索用时 0 毫秒
21.
ABSTRACT

Conditional tests are constructed by conditioning a fit measure to a minimal sufficient statistic. To calculate the p-value of these tests, Monte Carlo methods with co-sufficient samples can be used. In this paper we show how to simulate co-sufficient samples when the data distribution belongs to the exponential family with doubly transitive sufficient statistics. The proposed method is illustrated using the beta distribution.  相似文献   
22.
In this paper a specification strategy is proposed for the determination of the orders in ARMA models. The strategy is based on two newly defined concepts: the q-conditioned partial auto-regressive function and the p-conditioned partial moving average function. These concepts are similar to the generalized partial autocorrelation function which has been recently suggested for order determination. The main difference is that they are defined and employed in connection with an asymptotically efficient estimation method instead of the rather inefficient generalized Yule-Walker method. The specification is performed by using sequential Wald type tests. In contrast to the traditional testing of hypotheses, these tests use critical values which increase with the sample size at an appropriate rate  相似文献   
23.
Time series analyses of monthly average total ozone measured at 37 stations throughout the world were used to estimate the extent to which the average ozone trend correlates with the depletion curve hypothesized as due to chlorofluorocarbons (CFCs). Statistical characteristics of stations in the ensemble were used to help define appropriate model and station selection criteria. The maximum likelihood procedure developed herein estimates the weighted average trend, its. variance, and the intra- and inter-station variance components of the trend. Correlations among trends at different stations are also taken into account. The models were subjected to much checking and criticism. Variations in statistical methodology are used to show that the results are insensitive to details of the model selection criteria. The method does not discriminate well between the hypothesized CFC trend and a linear trend. The trend estimates represent the sum of all long-term global effects. The variance includes all effects that differ from station-to-station. The estimated trend and 2α limits for 14 stations with 20-year records (1958-79) is an ozone increase through 1979 of (1.5+1.0) percent. At the 23 stations with shorter records, the trend is (1.0=1.7) percent. It is concluded that no significant depletion in stratospheric ozone has occurred from any cause through the end of 1979.  相似文献   
24.
25.
The estimation of the parameters of two or more geometric distribuionsis considered by usinq an empirical Bayesian approach. Robbins (1983) gave empirical Bayes estimates if the number of distributions N is large, buthere we consider the cascwhore N is small. The parameters of the prior distribution areest imated by looking at maximum like lihood and momentest imation methods.  相似文献   
26.
Questions related to lotteries are usually of interest to the public since people think there is a magic formula which will help them to win lottery draws. This note shows how to compute the expected waiting time to observe specific numbers in a sequence of lottery draws and show that surprising facts are expected to occur.  相似文献   
27.
This paper surveys recent developments in the strong law of large numbers for dependent heterogeneous processes. We prove a generalised version of a recent strong law for Lz-mixingales, and also a new strong law for Lpmixingales. These results greatly relax the dependence and heterogeneity conditions relative to those currently cited, and introduce explicit trade-offs between dependence and heterogeneity. The results are applied to proving strong laws for near-epoch dependent functions of mixing processes. We contrast several methods for obtaining these results, including mapping directly to the mixingale properties, and applying a truncation argument.  相似文献   
28.
Previous research suggests that when there is a high level of inequality, there is a low rate of participation. Two arguments are generally offered: First, inequality depresses participation because people from different status groups have fewer opportunities to share common goals. Second, people may participate more in civic and social life when they have more resources. However, until now, these explanations have not been separated empirically. Using EU-SILC data for 24 European countries, we analyze how income inequality is related to civic and social participation. Our results indicate that the main effects of inequality manifest via resources at the individual and societal level. However, independent of these resources, higher inequality is associated with lower civic participation. Furthermore, inequality magnifies the relationship between income and participation. This finding is in line with the view that inter-individual processes explain why inequality diminishes participation.  相似文献   
29.
European Journal of Population - Using unique longitudinal data from the Dutch population registers, this study investigates the patterns and drivers of emigration of the Turkish second generation...  相似文献   
30.
土地资源可持续利用概念的理性思考   总被引:17,自引:0,他引:17  
在深入研究土地利用与可持续发展关系的基础上 ,提出土地资源可持续利用概念的新定义 ,进而以土地利用生态经济系统为分析框架 ,对土地利用可持续性内涵的作出合理解释。土地资源可持续利用是能够不断满足人类可持续发展需要的土地利用 ,其内在本质是要建立和保持一个运行良好的土地利用系统 ,土地利用的可持续性指的是系统运行在不断增加人类产出效益的同时不妨碍该系统再运行能力的连续保持和提高  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