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   7119篇
  免费   536篇
  国内免费   98篇
管理学   2797篇
民族学   10篇
人口学   83篇
丛书文集   296篇
理论方法论   394篇
综合类   2954篇
社会学   508篇
统计学   711篇
  2024年   9篇
  2023年   130篇
  2022年   96篇
  2021年   106篇
  2020年   252篇
  2019年   241篇
  2018年   237篇
  2017年   270篇
  2016年   262篇
  2015年   273篇
  2014年   402篇
  2013年   672篇
  2012年   460篇
  2011年   442篇
  2010年   370篇
  2009年   344篇
  2008年   363篇
  2007年   370篇
  2006年   374篇
  2005年   375篇
  2004年   290篇
  2003年   255篇
  2002年   200篇
  2001年   185篇
  2000年   105篇
  1999年   95篇
  1998年   56篇
  1997年   52篇
  1996年   43篇
  1995年   41篇
  1994年   57篇
  1993年   41篇
  1992年   34篇
  1991年   30篇
  1990年   39篇
  1989年   24篇
  1988年   32篇
  1987年   22篇
  1986年   19篇
  1985年   13篇
  1984年   18篇
  1983年   17篇
  1982年   17篇
  1981年   16篇
  1980年   1篇
  1979年   2篇
  1977年   1篇
排序方式: 共有7753条查询结果,搜索用时 15 毫秒
61.
目前,学术界对选取何种风险调整贴现率期限结构还存在争议,导致对同类投资项目得 出不同的管理指引意见. 针对这一争议,本文通过划分资本产出方式, 寻找影响贴现率结构的 主要因素. 研究表明,不确定的宏观经济产出和项目非系统风险共同影响风险溢价系数, 同时 风险溢价系数决定贴现率期限结构. 其中,当风险溢价系数大于某确定阈值, 贴现率随时间递 增; 其余情况表现为递减.  相似文献   
62.
One of the most dynamic and fruitful areas of current health‐related research concerns the various roles of the human microbiome in disease. Evidence is accumulating that interactions between substances in the environment and the microbiome can affect risks of disease, in both beneficial and adverse ways. Although most of the research has concerned the roles of diet and certain pharmaceutical agents, there is increasing interest in the possible roles of environmental chemicals. Chemical risk assessment has, to date, not included consideration of the influence of the microbiome. We suggest that failure to consider the possible roles of the microbiome could lead to significant error in risk assessment results. Our purpose in this commentary is to summarize some of the evidence supporting our hypothesis and to urge the risk assessment community to begin considering and influencing how results from microbiome‐related research could be incorporated into chemical risk assessments. An additional emphasis in our commentary concerns the distinct possibility that research on chemical–microbiome interactions will also reduce some of the significant uncertainties that accompany current risk assessments. Of particular interest is evidence suggesting that the microbiome has an influence on variability in disease risk across populations and (of particular interest to chemical risk) in animal and human responses to chemical exposure. The possible explanatory power of the microbiome regarding sources of variability could reduce what might be the most significant source of uncertainty in chemical risk assessment.  相似文献   
63.
《Risk analysis》2018,38(5):929-946
Graphs show promise for improving communications about different types of risks, including health risks, financial risks, and climate risks. However, graph designs that are effective at meeting one important risk communication goal (promoting risk‐avoidant behaviors) can at the same time compromise another key goal (improving risk understanding). We developed and tested simple bar graphs aimed at accomplishing these two goals simultaneously. We manipulated two design features in graphs, namely, whether graphs depicted the number of people affected by a risk and those at risk of harm (“foreground+background”) versus only those affected (“foreground‐only”), and the presence versus absence of simple numerical labels above bars. Foreground‐only displays were associated with larger risk perceptions and risk‐avoidant behavior (i.e., willingness to take a drug for heart attack prevention) than foreground+background displays, regardless of the presence of labels. Foreground‐only graphs also hindered risk understanding when labels were not present. However, the presence of labels significantly improved understanding, eliminating the detrimental effect of foreground‐only displays. Labels also led to more positive user evaluations of the graphs, but did not affect risk‐avoidant behavior. Using process modeling we identified mediators (risk perceptions, understanding, user evaluations) that explained the effect of display type on risk‐avoidant behavior. Our findings contribute new evidence to the graph design literature: unlike what was previously feared, we demonstrate that it is possible to design foreground‐only graphs that promote intentions for behavior change without a detrimental effect on risk understanding. Implications for the design of graphical risk communications and decision support are discussed.  相似文献   
64.
现代经济主体间网络关联性越来越强,风险很容易在不同行业间扩散,因此有效识别并分析系统性风险是防范金融危机的关键步骤。基于条件风险价值(CoVaR)和边际期望损失(MES)两个指标,对巨潮行业指数系统性风险的静态和动态特征进行了研究。结果发现,各行业间系统性风险的相关性较强,动态特征显示2009年年初和2016年3月为系统性风险的两个峰值;从分行业来看,材料行业的系统性风险最高,而消费和医药行业的系统性风险最低。采用动态面板模型分析影响行业系统性风险的市场面因素发现,短期涨幅较高、长期涨幅较低及流动性较充分的行业,其系统性风险往往更低。因此,应加强对系统性风险较高行业的监管力度,建立好金融防火墙,防止外部金融风险的过度传染;同时应加强对各行业的实时监控,尤其是关注短期暴涨暴跌及流动性充分与否的监控。  相似文献   
65.
As part of the celebration of the 40th anniversary of the Society for Risk Analysis and Risk Analysis: An International Journal, this essay reviews the 10 most important accomplishments of risk analysis from 1980 to 2010, outlines major accomplishments in three major categories from 2011 to 2019, discusses how editors circulate authors’ accomplishments, and proposes 10 major risk-related challenges for 2020–2030. Authors conclude that the next decade will severely test the field of risk analysis.  相似文献   
66.
随着房地产调控和城市化进程的加快,商业地产越来越受到开发商的青睐。城市综合体作为商业地产的典型代表以其多结构多层级的功能组合迅速提升区域价值而拥有了“城中之城”的美誉,在东部地区二三线城市大量涌现。但城市综合体带动城市发展的同时,也引发了一系列风险亟待关注。  相似文献   
67.
Delay discounting (DD) is a measure of impulsivity that describes the subjective decline in value of a consequence as the delay to that consequence increases. We sought to assess whether the results of a monetary DD task would be predictive of sexual risk-taking in a group of Internet-using men who have sex with men (MSM). 1402 participants completed an online survey that included questions about the participant’s demographics, sexual history and behavior, drug use, sexual compulsivity, and a monetary DD task. High DD was associated with increased odds of reporting >2 UAI partners in the past 12 months [aOR = 1.5 (1.1–2.1)]. Future studies should examine the utility of DD as a predictor of risky sexual behavior, as well as explore the possibility of HIV prevention interventions targeting DD.  相似文献   
68.
The argument is made for having a positive error culture in child protection to improve decision‐making and risk management. This requires organizations to accept that mistakes are likely and to treat them as opportunities for learning and improving. In contrast, in many organizations, a punitive reaction to errors leads to workers hiding them and developing a defensive approach to their practice with children and families. The safety management literature has shown how human error is generally not simply due to a “bad apple” but made more or less likely by the work context that helps or hinders good performance. Improving safety requires learning about the weaknesses in the organization that contribute to poor performance. To create a learning culture, people need to feel that when they talk about mistakes or weak practice, there will be a constructive response from their organization. One aspect of reducing the blame culture is to develop a shared understanding of how practice will be judged and how those appraising practice will avoid the hindsight bias. To facilitate a positive error culture, a set of risk principles are presented that offer a set of criteria by which practice should be appraised.  相似文献   
69.
This study investigated the risk factors associated with the occurrence of child physical and psychological abuse in South Korea based on the ecological theory of child maltreatment. A subsample of 3‐ to 18‐year‐old children from “A Study on the Current State of Child Abuse and Neglect,” a nationally representative study on child abuse and neglect, was utilized for secondary data analysis. The sample was divided into two age groups (third graders in elementary school and below and fourth graders and above). We utilized hierarchical logistic regression for each age group separately to analyze the data. The variables at each level of the system (i.e., ontogenic development, microsystem, and exosystem) were entered into the model in sequential order. The results showed the common risk factors for both age groups are the caregiver's experience of abuse in childhood, the child's problem behavior, exposure to domestic violence, community size, and informal social control. The child's age was also significant in both groups but in the opposite direction. Social support was a significant predictor for the younger age group only, while the caregiver's level of education was significant for the older age group only. Implications for future research and practice are discussed based on the study results.  相似文献   
70.
This study uses a simple metric to assess the degree of risk an individual player takes on while gambling. The player’s average potential gross win per bet placed captures both the amount of money put at risk and the volatility of returns, each of which will be correlated with risk of gambling harm. To illustrate the potential usefulness of this metric, the study analyses individual account data relating to online bets on horse racing. Analysing total stakes, the traditional indicator of risk taking, and applying ordinary least squares regression, the greatest risk takers appear to be males in their mid-fifties. Using the new metric and applying quantile regression to allow a focus on heavier bettors, the highest risk takers are shown as substantially younger, males around 30. Choice of metric and estimation method therefore matter and the approach proposed here could be used by operators to identify which online players take greatest risks.  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