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   3148篇
  免费   95篇
  国内免费   1篇
管理学   491篇
民族学   15篇
人才学   1篇
人口学   250篇
丛书文集   25篇
理论方法论   336篇
综合类   23篇
社会学   1694篇
统计学   409篇
  2023年   18篇
  2021年   12篇
  2020年   37篇
  2019年   55篇
  2018年   68篇
  2017年   77篇
  2016年   78篇
  2015年   52篇
  2014年   66篇
  2013年   532篇
  2012年   96篇
  2011年   85篇
  2010年   77篇
  2009年   83篇
  2008年   99篇
  2007年   100篇
  2006年   100篇
  2005年   103篇
  2004年   101篇
  2003年   102篇
  2002年   110篇
  2001年   61篇
  2000年   54篇
  1999年   66篇
  1998年   53篇
  1997年   64篇
  1996年   71篇
  1995年   41篇
  1994年   47篇
  1993年   47篇
  1992年   44篇
  1991年   48篇
  1990年   46篇
  1989年   37篇
  1988年   32篇
  1987年   33篇
  1986年   21篇
  1985年   25篇
  1984年   42篇
  1983年   39篇
  1982年   35篇
  1981年   47篇
  1980年   33篇
  1979年   24篇
  1978年   23篇
  1977年   30篇
  1976年   29篇
  1975年   17篇
  1974年   11篇
  1973年   21篇
排序方式: 共有3244条查询结果,搜索用时 31 毫秒
861.
The terms sweeping and alignment refer to the same process. Sweeping/alignment is used by data analysts as a technique for describing the effects of a model factor (e.g., treatments in a randomized block design) after the effects of nuisance parameters (e.g., blocks) have been removed from the data. In this paper sweeping/alignment is used as the basis for developing tests of factors in unbalanced experimental design models. Formulas are presented for treatment effects in randomized block designs with missing observations, and for interaction and main effects in unbalanced two-way factorial designs with empty cells.  相似文献   
862.
Data Splitting     
Data splitting is the act of partitioning available data into two portions, usually for cross-validatory purposes. One portion of the data is used to develop a predictive model and the other to evaluate the model's performance. This article reviews data splitting in the context of regression. Guidelines for splitting are described, and the merits of predictive assessments derived from data splitting relative to those derived from alternative approaches are discussed.  相似文献   
863.
We describe the design and analysis for a simulation experiment to compare the mean-squared errors (MSE's) of two quantile estimators defined for random walk designs. The dependence of the easily computed MSE of the first estimator on the levels of five factors is examined via multiple regression. This information is used to plan a simulation to compute the MSE of the second estimator using a fraction of a 3352factorial allowing uncorrelated estimates for all main effects and the two-factor interactions of a specified factor. Efficient estimation of the MSE of the second estimator is attempted through antithetic and control variate techniques of variance reduction, with modest success.  相似文献   
864.
The Gambling Passion Scale (GPS) is a recently developed research instrument for assessing individuals' passion for gambling. Because the psychometric properties of the GPS have only previously been examined in French Canadians, the aim of this study was to replicate previous psychometric findings in an English-speaking university sample. Participants (female: n = 58; male: n = 89) were drawn from a university campus based on self-reported experience with gambling indexed by scores on the South Oaks Gambling Screen (SOGS). The two-factor structure reported by Rousseau et al. (Journal of Gambling Studies, 18(1), pp. 45–66, 2002) was largely replicated in this sample, as were relationships between ‘obsessive passion’ and negative consequences stemming from gambling. These results support the validity of the GPS as a measure of gambling passion in English-speaking university gamblers and its potential to contribute to understanding problem gambling.  相似文献   
865.
This is an expository article. Here we show how the successfully used Kalman filter, popular with control engineers and other scientists, can be easily understood by statisticians if we use a Bayesian formulation and some well-known results in multivariate statistics. We also give a simple example illustrating the use of the Kalman filter for quality control work.  相似文献   
866.
This study deals with the deployment, utilization, and potential future employment opportunities for bachelor's-level social workers based on a survey of social service agencies in the Dallas-Fort Worth-Denton, Texas metropolitan area. Findings are presented in relation to social service agency reports concerning budgeted and vacant positions for different types of social service personnel, degree and academic fields specified for the positions, estimates concerning future social service personnel positions, preferences in hiring between undifferentiated bachelor's-level personnel and BSWs, and preferences in hiring between BSW and MSW personnel.  相似文献   
867.
868.
In 1980 the Joint Economic Committee completed the Special Study on Economic Change. This 20 volume, 3-year project, was premised on the fact that: ‘fundamental economic, social, political, international and technical conditions have changed, and are still changing markedly’. This suggests that conventional wisdom and established economic tools may not be equal to meeting the challenge of making sound policies in the economic sphere. The so-called laws of economics have not been repealed, but all guiding principles presuppose a certain environment of conditions, customs and practices—and when these change, the implementation of new policies and the modes of adjustment have to change also. This paper examines the problem of devising policy instruments for economic management, identifying the facts of the changing economic environment and the main difficulties facing world economic development.  相似文献   
869.
During the past decade the SBU (or portfolio) concept has enjoyed widespread popularity as a basis for corporate-wide strategic planning systems within large, diversified firms. This article discusses the implementation of such systems on the basis of 3 years of clinical and small sample research. A ‘basic model’ of implementation is used as a basis for comparison to progressive practice as observed in a sample of 13 firms. Furthermore, a new conceptual perspective for the portfolio concept is developed as a complement to the observed approach to implementation.  相似文献   
870.
This article presents a process for an integrated policy analysis that combines risk assessment and benefit-cost analysis. This concept, which explicitly combines the two types of related analyses, seems to contradict the long-accepted risk analysis paradigm of separating risk assessment and risk management since benefit-cost analysis is generally considered to be a part of risk management. Yet that separation has become a problem because benefit-cost analysis uses risk assessment results as a starting point and considerable debate over the last several years focused on the incompatibility of the use of upper bounds or "safe" point estimates in many risk assessments with benefit-cost analysis. The problem with these risk assessments is that they ignore probabilistic information. As advanced probabilistic techniques for risk assessment emerge and economic analysts receive distributions of risks instead of point estimates, the artificial separation between risk analysts and the economic/decision analysts complicates the overall analysis. In addition, recent developments in countervailing risk theory suggest that combining the risk and benefit-cost analyses is required to fully understand the complexity of choices and tradeoffs faced by the decisionmaker. This article also argues that the separation of analysis and management is important, but that benefit-cost analysis has been wrongly classified into the risk management category and that the analytical effort associated with understanding the economic impacts of risk reduction actions need to be part of a broader risk assessment process.  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