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   538篇
  免费   31篇
管理学   71篇
民族学   5篇
人口学   58篇
丛书文集   3篇
理论方法论   68篇
综合类   13篇
社会学   321篇
统计学   30篇
  2024年   1篇
  2023年   8篇
  2022年   6篇
  2021年   8篇
  2020年   18篇
  2019年   24篇
  2018年   37篇
  2017年   47篇
  2016年   33篇
  2015年   22篇
  2014年   27篇
  2013年   80篇
  2012年   32篇
  2011年   21篇
  2010年   23篇
  2009年   20篇
  2008年   19篇
  2007年   18篇
  2006年   15篇
  2005年   10篇
  2004年   13篇
  2003年   8篇
  2002年   13篇
  2001年   9篇
  2000年   2篇
  1999年   8篇
  1998年   3篇
  1997年   2篇
  1996年   2篇
  1995年   1篇
  1994年   4篇
  1993年   2篇
  1991年   4篇
  1990年   2篇
  1989年   5篇
  1988年   1篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
  1984年   6篇
  1983年   2篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1976年   1篇
  1974年   1篇
  1971年   1篇
  1966年   1篇
排序方式: 共有569条查询结果,搜索用时 125 毫秒
1.
To quantify the health benefits of environmental policies, economists generally require estimates of the reduced probability of illness or death. For policies that reduce exposure to carcinogenic substances, these estimates traditionally have been obtained through the linear extrapolation of experimental dose-response data to low-exposure scenarios as described in the U.S. Environmental Protection Agency's Guidelines for Carcinogen Risk Assessment (1986). In response to evolving scientific knowledge, EPA proposed revisions to the guidelines in 1996. Under the proposed revisions, dose-response relationships would not be estimated for carcinogens thought to exhibit nonlinear modes of action. Such a change in cancer-risk assessment methods and outputs will likely have serious consequences for how benefit-cost analyses of policies aimed at reducing cancer risks are conducted. Any tendency for reduced quantification of effects in environmental risk assessments, such as those contemplated in the revisions to EPA's cancer-risk assessment guidelines, impedes the ability of economic analysts to respond to increasing calls for benefit-cost analysis. This article examines the implications for benefit-cost analysis of carcinogenic exposures of the proposed changes to the 1986 Guidelines and proposes an approach for bounding dose-response relationships when no biologically based models are available. In spite of the more limited quantitative information provided in a carcinogen risk assessment under the proposed revisions to the guidelines, we argue that reasonable bounds on dose-response relationships can be estimated for low-level exposures to nonlinear carcinogens. This approach yields estimates of reduced illness for use in a benefit-cost analysis while incorporating evidence of nonlinearities in the dose-response relationship. As an illustration, the bounding approach is applied to the case of chloroform exposure.  相似文献   
2.
This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.  相似文献   
3.
4.
Studies of the determinants of English language ability have generally focused on the largest immigrant groups in the United States. Much less is known about smaller, but significant regional concentrations of immigrants and refugees. This article presents data on four very distinct and understudied groups: Russians, Somalis, Hmong, and Mexicans in the Midwest. We found large differences in English language proficiency across the different national origin groups, even after controlling for background variables. These differences were not attributable to refugee status or to linguistic distance from English. Being Somali, migrating to the United States at a young age and having a college diploma were the best predictors of both spoken and written proficiency. The returns to higher education were particularly noteworthy — respondents with college diplomas were more than 29 times more likely than non‐high school graduates to speak English well, and more than 20 times as likely to read well. Women appear to have benefited more than men from completing college in terms of spoken English proficiency since the male‐female gap narrows among the highly educated. Length of time in the United States was a good predictor of whether an individual speaks English at home, regardless of age of entry to the country.  相似文献   
5.
This study examined the emergence of affect specificity in infancy. In this study, infants received verbal and facial signals of 2 different, negatively valenced emotions (fear and sadness) as well as neutral affect via a television monitor to determine if they could make qualitative distinctions among emotions of the same valence. Twenty 12‐ to 14‐month‐olds and 20 16‐ to 18‐month‐olds were examined. Results suggested that younger infants showed no evidence of referential specificity, as they responded similarly to both the target and distracter toys, and showed no evidence of affect specificity, showing no difference in play between affect conditions. Older infants, in contrast, showed evidence both of referential and affect specificity. With respect to affect specificity, 16‐ to 18‐month‐olds touched the target toy less in the fear condition than in the sad condition and showed a larger proportion of negative facial expressions in the sad condition versus the fear condition. These findings suggest a developmental emergence after 15 months of age for affect specificity in relating emotional messages to objects.  相似文献   
6.
GM Foods and the Misperception of Risk Perception   总被引:3,自引:0,他引:3  
Public opposition to genetically modified (GM) food and crops is widely interpreted as the result of the public's misperception of the risks. With scientific assessment pointing to no unique risks from GM crops and foods, a strategy of accurate risk communication from trusted sources has been advocated. This is based on the assumption that the benefits of GM crops and foods are self-evident. Informed by the interpretation of some qualitative interviews with lay people, we use data from the Eurobarometer survey on biotechnology to explore the hypothesis that it is not so much the perception of risks as the absence of benefits that is the basis of the widespread rejection of GM foods and crops by the European public. Some respondents perceive both risks and benefits, and may be trading off these attributes along the lines of a rational choice model. However, for others, one attribute-benefit-appears to dominate their judgments: the lexicographic heuristic. For these respondents, their perception of risk is of limited importance in the formation of attitudes toward GM food and crops. The implication is that the absence of perceived benefits from GM foods and crops calls into question the relevance of risk communication strategies for bringing about change in public opinion.  相似文献   
7.
There is an absence of research on gambling among prison inmates during their incarceration. Little is known about how prisoners organize gambling activities or the potential risks they face from gambling. Similarly, no empirical attention has been given to how correctional institutions respond to inmate gambling. This study employed interviews with 55 male prisoners and self-administered surveys with 159 correctional officers and staff, at two medium security prisons in Ohio. Data were gathered on prevalence and patterns of inmate gambling, perceived hazards of gambling, and perceived institutional responses to prisoner gambling. Findings suggest that inmate gambling is common and constitutes an important feature of the underground economy of prisons, yet little is done to deter or prevent this activity. Suggestions are made for more effective institutional responses.  相似文献   
8.
ABSTRACT

Despite increasing societal acceptance of sexual-minority individuals, there are still gay, lesbian, and bisexual (GLB) adolescents who experience negative mental health outcomes. Minority stress theory posits that stigma-related stress associated with sexual-minority status drives increased risk among GLB individuals. Furthermore, recent evidence suggests that minority stress impacts emotion regulation (ER), identified as a particularly important risk factor for sexual-minority youth (SMY). Current research has identified some aspects of parenting contribute to GLB youth's mental health. We review the literature in these areas, and also integrate research from the broader developmental field on families and emotion socialization in order to identify the need for studies of parenting that go beyond existing data on parental acceptance and supportiveness of youth's sexual orientation. Limitations of the current literature and directions for future research are discussed, with specific focus on implications for interventions with SMY and their families.  相似文献   
9.
10.
Welfare state studies are usually motivated by one or both of two concerns: programme effects on the incidence of poverty, and the possibility of perverse incentive effects. Most research has been comparative, using cross‐national indicators from the Organisation for Economic Co‐operation and Development and other international organizations. That research often contrasts the generosity of programmes in a number of European countries and the lack of it in the USA. Focusing on income transfers after job‐loss, in this article we critically examine the comparative evidence on US welfare state generosity and then use the Panel Study of Income Dynamics (PSID) to estimate what happens to job‐losers' incomes. The comparative analysis suggests conclusions more nuanced than found in much of the literature. The PSID analysis shows how the income effects of job‐loss vary across job‐losers and suggests that the role of unemployment compensation programmes in supporting incomes may be overstated.  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