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   823篇
  免费   28篇
管理学   46篇
民族学   3篇
人口学   117篇
丛书文集   2篇
理论方法论   96篇
综合类   5篇
社会学   546篇
统计学   36篇
  2023年   4篇
  2021年   3篇
  2020年   17篇
  2019年   23篇
  2018年   25篇
  2017年   38篇
  2016年   23篇
  2015年   20篇
  2014年   22篇
  2013年   161篇
  2012年   27篇
  2011年   43篇
  2010年   26篇
  2009年   20篇
  2008年   43篇
  2007年   29篇
  2006年   23篇
  2005年   29篇
  2004年   22篇
  2003年   21篇
  2002年   31篇
  2001年   18篇
  2000年   18篇
  1999年   8篇
  1998年   10篇
  1997年   8篇
  1996年   12篇
  1995年   10篇
  1994年   11篇
  1993年   11篇
  1992年   6篇
  1991年   6篇
  1990年   6篇
  1989年   8篇
  1987年   9篇
  1986年   8篇
  1985年   12篇
  1984年   10篇
  1983年   4篇
  1982年   2篇
  1980年   2篇
  1979年   4篇
  1978年   1篇
  1977年   3篇
  1976年   5篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
  1970年   2篇
排序方式: 共有851条查询结果,搜索用时 15 毫秒
1.
Presidential elections are often seen as referendums on the health of the economy; however, little evidence exists on the president's ability to influence gross domestic product (GDP). This study examines the effect of the incentive to be reelected and the resulting increase in presidential effort on GDP growth. Growth is found to rise in reelection years for first‐term presidents after 1932 and to fall in election years before 1932, when reelection was uncommon, and for second‐term presidents generally. This effect is largest for high‐quality presidents—who probably have the highest return to effort—and is spread across multiple sectors of the economy. (JEL D78, D72, E32, J24)  相似文献   
2.
The authors use an ecological framework and grounded theoretical analysis to explore the circumstances in which working‐class and low‐income custodial African American fathers gain custody of their children, their transition from part‐time to full‐time parents, and the role of support networks in enhancing or inhibiting these men's parenting. Twenty‐four men from an impoverished Midwestern urban area participated in the study. The findings suggest that these men, and perhaps others sharing their demographic profiles, generally become parents by default and are often reluctant to take on a full‐time, single parenting role. Adaptation to the role seems to be enhanced by these men's use of extended kin support networks and shared living arrangements. However, low wages, a lack of sufficient assistance from public assistance programs, and informal custody arrangements often inhibit their fathering.  相似文献   
3.
Ohne Zusammenfassung German translations by Monika Lütke-Daldrup.  相似文献   
4.
Major policy changes like the 1986 Tax Reform Act (TRA) in the United States provide natural experiments to study attitudinal and behavior responses to law. Surprisingly, public evaluations of the TRA became increasingly negative after passage, while general support for the tax system became more positive in response to the changes. To explain this puzzle, we propose a dynamic model of taxpayer attitudes that is consistent with the observed loose linkage between logically-connected concepts. We briefly review the political context, objectives and impacts of the 1986 Tax Reform Act, and present several studies testing the impact of self-interest, prior beliefs, and social discussion on changes in attitudes and behavior.Results suggest that the complexity of taxes and difficulty in knowing objective impacts weakens the role of self-interest in attitudinal changes, thereby strengthening the role of prior beliefs and discussion. Evaluations of tax laws are most responsive to more politically-oriented influences.  相似文献   
5.
6.
Summary.  In studies to assess the accuracy of a screening test, often definitive disease assessment is too invasive or expensive to be ascertained on all the study subjects. Although it may be more ethical or cost effective to ascertain the true disease status with a higher rate in study subjects where the screening test or additional information is suggestive of disease, estimates of accuracy can be biased in a study with such a design. This bias is known as verification bias. Verification bias correction methods that accommodate screening tests with binary or ordinal responses have been developed; however, no verification bias correction methods exist for tests with continuous results. We propose and compare imputation and reweighting bias-corrected estimators of true and false positive rates, receiver operating characteristic curves and area under the receiver operating characteristic curve for continuous tests. Distribution theory and simulation studies are used to compare the proposed estimators with respect to bias, relative efficiency and robustness to model misspecification. The bias correction estimators proposed are applied to data from a study of screening tests for neonatal hearing loss.  相似文献   
7.
Mothers' time‐use patterns were compared in families in which infants spent more than 30 hours per week in child care (In‐Care group; n= 143) versus 0 hours per week (At‐Home group; n= 183) from birth to 6 months of age. In‐Care group mothers spent about 12 fewer hours per week interacting with their infants, for about 32% less time; fathers of these infants were more involved in caregiving. The groups did not differ in the quality of mother‐infant interaction. In the In‐Care group, quantity of interaction was related to greater separation anxiety and concerns about effects of maternal employment. Time‐use data were not related to child outcomes at 15 months of age. Results suggest that the effect of extensive time spent apart on the quantity and quality of mother‐infant interaction may be smaller than anticipated.  相似文献   
8.
What do novice word learners know about the sound of words? Word‐learning tasks suggest that young infants (14 months old) confuse similar‐sounding words, whereas mispronunciation detection tasks suggest that slightly older infants (18–24 months old) correctly distinguish similar words. Here we explore whether the difficulty at 14 months stems from infants' novice status as word learners or whether it is inherent in the task demands of learning new words. Results from 3 experiments support a developmental explanation. In Experiment 1, infants of 20 months learned to pair 2 phonetically similar words to 2 different objects under precisely the same conditions that infants of 14 months (Experiment 2) failed. In Experiment 3, infants of 17 months showed intermediate, but still successful, performance in the task. Vocabulary size predicted word‐learning performance, but only in the younger, less experienced word learners. The implications of these results for theories of word learning and lexical representation are discussed.  相似文献   
9.
10.
Time Use, Gender, and Public Policy Regimes   总被引:1,自引:0,他引:1  
  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