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   4348篇
  免费   146篇
管理学   533篇
民族学   40篇
人才学   1篇
人口学   447篇
丛书文集   26篇
理论方法论   557篇
综合类   53篇
社会学   2065篇
统计学   772篇
  2023年   54篇
  2022年   23篇
  2021年   63篇
  2020年   140篇
  2019年   186篇
  2018年   205篇
  2017年   247篇
  2016年   196篇
  2015年   133篇
  2014年   150篇
  2013年   767篇
  2012年   203篇
  2011年   186篇
  2010年   151篇
  2009年   127篇
  2008年   132篇
  2007年   131篇
  2006年   130篇
  2005年   109篇
  2004年   108篇
  2003年   97篇
  2002年   83篇
  2001年   65篇
  2000年   53篇
  1999年   63篇
  1998年   47篇
  1997年   41篇
  1996年   45篇
  1995年   42篇
  1994年   52篇
  1993年   43篇
  1992年   52篇
  1991年   37篇
  1990年   20篇
  1989年   24篇
  1988年   26篇
  1987年   17篇
  1986年   15篇
  1985年   27篇
  1984年   22篇
  1983年   20篇
  1982年   16篇
  1981年   23篇
  1980年   19篇
  1979年   17篇
  1978年   11篇
  1977年   6篇
  1976年   14篇
  1975年   12篇
  1974年   13篇
排序方式: 共有4494条查询结果,搜索用时 15 毫秒
91.
This paper proposes a set of definitions for the concepts “validation” and “assessment” applied to expert systems (ESs). It develops a framework for this validation and demonstrates the framework on existing accounting and auditing ESs to elicit some of the research issues involved in ES validation. Validation is critical to the design and implementation of decision-making ESs. In a setting where objectivity is sought and variance is avoided, validation ascertains what a system knows, knows incorrectly, or does not know. Validation ascertains the system's level of expertise and investigates the theoretical basis on which the system is based. It evaluates the reliability of decisions made by the system. The validation framework developed in this paper is research methods. It is designed to reflect the unique aspects of ESs (in contrast to other types of computer programs) and can be used by ES developers as a basis from which to perform validation and by researchers as a framework to elicit research issues in validation.  相似文献   
92.
Decision analysis tools often are used in semistructured and ill-structured situations. While some researchers have argued that computerized decision analysis programs may improve decision quality in such situations, research support for this assertion is weak. In this laboratory study, business students used a computerized decision-analysis program with short strategic-management cases to prepare decision reports. Independent raters' perceptions of aided and unaided decision performance were contrasted, attitudes of students toward the program were assessed, individual differences were correlated with attitudes, and the program's impact on students' perceptions of their decision processes and performance was examined. Student attitudes toward the computerized aid were favorable, and individual differences in reactions generally were as predicted. However, the program did not improve the independent ratings of students' decision reports and recommendations. These findings suggest that computerized decision aids should be adopted cautiously. If such aids result in positive user affect and heightened decision confidence without corresponding improvements in decision quality, they may be dysfunctional. Rigorous research methodologies which incorporate independent evaluations of analyses and decisions are recommended for use in future research on computerized decision-analysis programs.  相似文献   
93.
In the 1967 Harvard-Cornell football game, Harvard was ahead 14–0 late in the game when Cornell scored two touchdowns. On both occasions, Cornell tried and failed on the two-point conversion attempt and lost the game 14–12. Postgame arguments were divided on the merits of Cornell's strategy. For this frequently occurring scenario in college football, we derive a maximum expected utility decision rule for the decision of kicking versus running/passing based on the relative utility of a win, a tie, or a loss and the probabilities of success with a kick as opposed to a run/pass.  相似文献   
94.
In this paper, we consider a Bayesian analysis of the unbalanced (general) growth curve model with AR(1) autoregressive dependence, while applying the Box-Cox power transformations. We propose exact, simple and Markov chain Monte Carlo approximate parameter estimation and prediction of future values. Numerical results are illustrated with real and simulated data.  相似文献   
95.
For two response variables y t and y c corresponding to two treatments for two policies) T and C , we wish to learn about quantiles of y t− y c from the marginal quantiles of y t and y c; only one of y t and y c is observed for an individual. We find that, in general, this is difficult for quantiles other than the median unless strong assumptions are imposed on how y t is related to y c. For the median, we present conditions under which the sign of the median treatment effect is identified.  相似文献   
96.
We show that, in the context of double-bootstrap confidence intervals, linear interpolation at the second level of the double bootstrap can reduce the simulation error component of coverage error by an order of magnitude. Intervals that are indistinguishable in terms of coverage error with theoretical, infinite simulation, double-bootstrap confidence intervals may be obtained at substantially less computational expense than by using the standard Monte Carlo approximation method. The intervals retain the simplicity of uniform bootstrap sampling and require no special analysis or computational techniques. Interpolation at the first level of the double bootstrap is shown to have a relatively minor effect on the simulation error.  相似文献   
97.
Religiosity's impact on adolescent educational outcomes has been widely documented in the sociology of religion literature. Building upon King's conceptual framework of ideological, social, and transcendent resources that are made available to youth through religious participation, we use qualitative and quantitative data from the National Study of Youth and Religion (NSYR) to explore how the associations between religious involvement and educational outcomes may vary among lower and higher socioeconomic status youth. Our findings indicate significant positive effects of transcendent and ideological resources on educational outcomes, especially among youth from disadvantaged backgrounds, but limited influence of social resources through youth's religious participation.  相似文献   
98.
Urban Ecosystems - Urbanization-induced habitat loss and alteration causes significant challenges for the survival of many species. Identifying how species respond to urbanization can yield...  相似文献   
99.
Lee  Catherine  Park  Chan Ryul 《Urban Ecosystems》2019,22(2):227-233
Urban Ecosystems - Anthropogenic noise may mask effective vocal signal transmission by birds, particularly in notes occurring in lower frequencies. Previous studies have shown a correlation of...  相似文献   
100.
Despite policy efforts to increase adolescent happiness, their impact has been unsatisfactory. Their limited impact may be rooted from a discrepancy between values that adolescents pursued and those that the policies were based on. To provide policy implications, our study aims to identify prevailing values for South Korean, Japanese, and Chinese adolescents and to examine the relationship between the values and self-rated happiness (SRH). A cross-sectional study was conducted using survey data collected on approximately 2000 middle and high school students (7th to 12th school grade) from each country in 2008. Firstly, an explanatory factor analysis was conducted to identify salient adolescent values from each country. Subsequently, a multiple logistic regression analysis was conducted for each population group to examine the relationship between the identified values and adolescent SRH after controlling for sociodemographic characteristics. We found that benevolence and altruism were positively associated with adolescent SRH in all three population groups. Patriarchy was associated with SRH positively in Chinese yet inversely in Japanese. Success pursuit was inversely associated with SRH in Korean. Policy efforts based on values of communities or social harmony may benefit adolescents’ SRH in these three countries.  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