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   247篇
  免费   9篇
管理学   23篇
人口学   22篇
理论方法论   29篇
综合类   2篇
社会学   160篇
统计学   20篇
  2023年   2篇
  2022年   2篇
  2021年   4篇
  2020年   5篇
  2019年   11篇
  2018年   7篇
  2017年   10篇
  2016年   9篇
  2015年   7篇
  2014年   7篇
  2013年   44篇
  2012年   3篇
  2011年   8篇
  2010年   5篇
  2009年   4篇
  2008年   11篇
  2007年   6篇
  2006年   6篇
  2005年   10篇
  2004年   2篇
  2003年   6篇
  2002年   9篇
  2001年   7篇
  2000年   3篇
  1997年   3篇
  1996年   3篇
  1995年   6篇
  1994年   4篇
  1993年   2篇
  1992年   3篇
  1991年   4篇
  1990年   2篇
  1989年   1篇
  1988年   3篇
  1987年   3篇
  1986年   2篇
  1985年   4篇
  1984年   3篇
  1983年   2篇
  1982年   4篇
  1981年   1篇
  1980年   5篇
  1979年   2篇
  1978年   2篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1969年   2篇
排序方式: 共有256条查询结果,搜索用时 218 毫秒
81.
In less than a decade, children who provide care for ill or disabled parents and siblings have become a major target of social welfare services. 'Young carers' suffer, it is suggested, from a degradation in mental and physical health, have damaged educational careers, restricted social networks, and will suffer long-term consequences in adult life as a result of their childhood caring roles. This paper argues that limited empirical evidence exists for these claims and that, where legitimate concerns arise, they are frequently related to poverty, social exclusion, and unsupported or inadequate parenting, and have no direct relationship to illness or impairment. While dedicated services to young carers have made a valuable contribution in highlighting an important social issue, a radical review of their place in the overall structure of support services for families affected by illness or disability is long overdue.  相似文献   
82.
Longer life expectancy, rapid population growth, and low exercise-participation rates of adults 65 and older justify the need for better understanding of older adults' exercise behavior. The objectives of this focus-group study were to determine barriers to the exercise behavior of older adults. Six focus groups, three with exercisers and three with nonexercisers, were conducted at various sites throughout Rhode Island. The majority (n = 57) of the 66 individuals who participated were women, and all stated that they were 65 and older. Results from the focus-group data identified 13 barriers to exercise behavior. The most significant barriers mentioned by nonexercisers were fear of falling, inertia, and negative affect. Exercisers identified inertia, time constraints, and physical ailments as being the most significant barriers to exercise. Implications from these focus-group data can be useful in the development of exercise interventions for older adults, which could increase exercise participation.  相似文献   
83.
Objective. Arthur Okun made plain the fundamental conflict between efficiency and equity that arises in the pursuit of policy goals ( Okun, 1974 ). Although Okun was speaking about government tax and spending policy, the potential conflict between efficiency and equity is also manifest at the nexus of two of the most far‐reaching changes in the environmental policy arena: the adoption of market‐like tools for pollution control and the quest for environmental justice. The article assesses this potential tradeoff by determining whether the pursuit of efficiency through the Clean Air Act Amendment's (CAA) sulfur dioxide allowance trading program (ATP) inadvertently transfers pollution into poor and minority communities. Methods. I employ Probit, Tobit, and GLS models using data for all SO2 trading activity between January 1995 and March 2009 to estimate whether allowance trading concentrates SO2 emissions in poor communities and communities of color. When using these models, I control for sample selectivity and for possible bias stemming from the modifiable areal unit problem. Results. The ATP does not concentrate sulfur dioxide emissions in black or Hispanic communities. To the contrary, communities with high percentages of black and Hispanic residents experience fewer imports of sulfur dioxide. Allowance trading does transfer SO2 emissions into poorly educated communities. Conclusions. There is no inherent tradeoff between efficiency and equity when using market‐based instruments for pollution control. Policymakers, however, might make an effort to design and implement future emissions trading programs in a manner that reduces the monitoring costs of tracking emissions trading. By reducing monitoring costs, policymakers may prevent the concentration of emissions in poorly educated communities while preserving the efficiency benefits of these instruments.  相似文献   
84.
Rochelle S. Newman 《Infancy》2011,16(5):447-470
Infants and toddlers are often spoken to in the presence of background sounds, including speech from other talkers. Prior work has suggested that infants 1 year of age and younger can only recognize speech when it is louder than any distracters in the environment. The present study tests 24‐month‐olds’ ability to understand speech in a multitalker environment. Children were presented with a preferential‐looking task in which a target voice told them to find one of two objects. At the same time, multitalker babble was presented as a distracter, at one of four signal‐to‐noise ratios. Children showed some ability to understand speech and look at the appropriate referent at signal‐to‐noise ratios as low as ?5 dB. These findings suggest that 24‐month‐olds are better able to selectively attend to an interesting voice in the context of competing distracter voices than are younger infants. There were significant correlations between individual children’s performance and their vocabulary size, but only at one of the four noise levels; thus, it does not appear that vocabulary size is the driving factor in children’s listening improvement, although it may be a contributing factor to performance in noisy environments.  相似文献   
85.
Cass Sunstein and Richard Thaler’s Nudge: Improving Decisions about Health, Wealth, and Happiness presents an influential account of why ‘choice architecture’ should be used to ‘nudge’ people into making better decisions than they would otherwise make. In this essay we: (1) explain the main concepts that Thaler and Sunstein rely upon to defend their project; (2) clarify the main conceptual problems that have arisen in discussions about nudges; (3) clarify practical difficulties that can arise during nudge practice; (4) review the main ethical and political objections that have been raised against nudging; and (5) clarify why issues related to meaning can pose methodological problems for creating effective choice architecture.  相似文献   
86.
The Social and Sensory Environment Studies of very low birthweight infants have quantified the amount and quality of social interaction with staff and parents and described the sound environment in an incubator. The present study concerns preterm infant behavior and reactions to these stimuli with particular reference to approach and withdrawal and vocalization. Among the findings are that while intermittent vocalization increases, infant cry decreases over the first three weeks in the incubator. Approach activities take place with some consistency whereas withdrawal differs from child to child. The ethnographic focus on interactive components of the intensive care experience documents the process of intersubjective development for the purpose of locating and isolating points of vulnerability in language and cognitive skills of infants born at very low birthweight.  相似文献   
87.
The Analysis of Verbal Behavior - The experiment reported here represents a partial replication of an experiment by Newman, Buffington, and Hemmes (in press) and analyzes responding in college...  相似文献   
88.
IS THE BUDGET DEFICIT “TOO LARGE”?: SOME FURTHER EVIDENCE   总被引:1,自引:0,他引:1  
The size of the federal budget deficit has alarmed politicians and the general public both. Following recent work, we examine the long-run solvency of the U.S. government by testing for cointegration of federal expenditures and revenues. We include a break term in the cointegrating recession for 1981 to capture a shift in the fiscal process in the first Reagan administration. Tests show the break to be significant; and with the break, in contrast to earlier work, expenditures and revenues are cointegrated with a coefficient of one. Thus, we find the deficit to be stationary and so potentially sustainable.  相似文献   
89.
90.
Fitness is the currency of natural selection, a measure of the propagation rate of genotypes into future generations. Its various definitions have the common feature that they are functions of survival and fertility rates. At the individual level, the operative level for natural selection, these rates must be understood as latent features, genetically determined propensities existing at birth. This conception of rates requires that individual fitness be defined and estimated by consideration of the individual in a modelled relation to a group of similar individuals; the only alternative is to consider a sample of size one, unless a clone of identical individuals is available. We present hierarchical models describing individual heterogeneity in survival and fertility rates and allowing for associations between these rates at the individual level. We apply these models to an analysis of life histories of Kittiwakes ( Rissa tridactyla ) observed at several colonies on the Brittany coast of France. We compare Bayesian estimation of the population distribution of individual fitness with estimation based on treating individual life histories in isolation, as samples of size one (e.g. McGraw & Caswell, 1996).  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