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   171篇
  免费   12篇
管理学   8篇
民族学   1篇
人口学   11篇
理论方法论   43篇
综合类   1篇
社会学   101篇
统计学   18篇
  2023年   3篇
  2022年   1篇
  2021年   2篇
  2020年   5篇
  2019年   14篇
  2018年   8篇
  2017年   10篇
  2016年   5篇
  2015年   4篇
  2014年   3篇
  2013年   33篇
  2012年   4篇
  2011年   15篇
  2010年   3篇
  2009年   6篇
  2008年   8篇
  2007年   7篇
  2006年   6篇
  2005年   8篇
  2004年   4篇
  2003年   4篇
  2002年   3篇
  2001年   2篇
  2000年   1篇
  1999年   5篇
  1998年   2篇
  1997年   1篇
  1996年   1篇
  1995年   2篇
  1993年   1篇
  1991年   1篇
  1990年   3篇
  1989年   2篇
  1987年   3篇
  1986年   1篇
  1970年   1篇
  1967年   1篇
排序方式: 共有183条查询结果,搜索用时 31 毫秒
1.
To capture mean and variance asymmetries and time‐varying volatility in financial time series, we generalize the threshold stochastic volatility (THSV) model and incorporate a heavy‐tailed error distribution. Unlike existing stochastic volatility models, this model simultaneously accounts for uncertainty in the unobserved threshold value and in the time‐delay parameter. Self‐exciting and exogenous threshold variables are considered to investigate the impact of a number of market news variables on volatility changes. Adopting a Bayesian approach, we use Markov chain Monte Carlo methods to estimate all unknown parameters and latent variables. A simulation experiment demonstrates good estimation performance for reasonable sample sizes. In a study of two international financial market indices, we consider two variants of the generalized THSV model, with US market news as the threshold variable. Finally, we compare models using Bayesian forecasting in a value‐at‐risk (VaR) study. The results show that our proposed model can generate more accurate VaR forecasts than can standard models.  相似文献   
2.
3.
4.
5.
This article uses two CGE macro‐micro models to analyse the distributional impact of the food crisis and policy responses in two neighbouring African countries, both of which are strongly dependent on agriculture. The approach captures structural differences at both the macro and micro level for household income and expenditure structures, and the results reveal differences for poverty impact at the national and sub‐group levels, as well as for inequality and pro‐poor analysis. The importance of country‐specific analysis and the risk of extrapolating conclusions from one country to another are also highlighted.  相似文献   
6.
Physical activity is a well recognized approach to the enhancement of general health and wellbeing in both healthy and diseased populations. However, excessive activity can result in exercise-related menstrual dysfunction (ERMD), which can adversely affect bone health and increase the risk of infertility and cardiovascular events in later life. Physicians should maintain a high awareness of EMRD in assessing health risks in the menopausal woman.  相似文献   
7.
This paper proposes a new hysteretic vector autoregressive (HVAR) model in which the regime switching may be delayed when the hysteresis variable lies in a hysteresis zone. We integrate an adapted multivariate Student-t distribution from amending the scale mixtures of normal distributions. This HVAR model allows for a higher degree of flexibility in the degrees of freedom for each time series. We use the proposed model to test for a causal relationship between any two target time series. Using posterior odds ratios, we overcome the limitations of the classical approach to multiple testing. Both simulated and real examples herein help illustrate the suggested methods. We apply the proposed HVAR model to investigate the causal relationship between the quarterly growth rates of gross domestic product of United Kingdom and United States. Moreover, we check the pairwise lagged dependence of daily PM2.5 levels in three districts of Taipei.  相似文献   
8.
Drawing from literature regarding public engagement, the Elaboration Likelihood Model (ELM), computer-mediated communication research, and emotion psychology, this study examines the effects of companies’ social media communication strategies on public engagement behaviors as indexed by post likes, shares, and comments. Specifically, it investigates how corporate Facebook posts’ functional traits (functional interactivity and vividness) and emotional traits (emotion presence, valence, and strength) impact public engagement online. Through data mining and computer-assisted sentiment analysis of 33,379 posts from 106 Standard & Poor 500 companies’ Facebook accounts, this study finds a negative effect of functional interactivity but a positive effect of vividness on engagement. It also shows that emotional traits overall yield stronger public engagement outcomes. Two-way interactions between emotional and functional features are also detected. Theoretical and practical implications are discussed.  相似文献   
9.
The majority of children and young people removed from the care of their parents by the state of Victoria, Australia, reside in foster or kinship care. These children have experienced a broad range of adverse conditions and are up to 4 times more likely to experience problems with mental health than their mainstream peers. This paper draws on the perspectives of foster and kinship carers, describing the disconnection between their role as mental health advocates and their interest in early intervention in a field which is dominated by crisis and the historic marginalisation of foster and kinship carers. Thirty‐one foster and kinship carers across greater metropolitan Melbourne, Australia, contributed to this study through interviews and focus groups. Participants demonstrated a practical understanding of mental health and an ability to identify a range of conditions that have an adverse impact on the mental health of children and young people in their care. The paper concludes that there is a lack of systemic support and even a range of barriers that affect the capacity of foster and kinship carers to promote the mental health and well‐being of the children and young people in their care.  相似文献   
10.
This study examined the clinical significance of career counseling effects. Participants were 111 university students (83% women) who participated in individual career counseling sessions at their university. All participants completed the French version of the Outcome Questionnaire–30.2 (OQ‐30.2; Lambert, Finch, Okiishi, & Burlingame, 2005) immediately before the 1st session (pretest) and at the beginning of the last session (posttest). The OQ‐30.2 assesses 3 client life domains: subjective discomfort, problems in interpersonal relationships, and problems in social role satisfaction. Using Jacobson and Truax’s (1991) statistical approach to assessing clinical change, the authors compared clients’ pretest OQ‐30.2 scores with their posttest scores. Among clients with a “dysfunctional” score (n = 59) at the study’s inception, 34% recovered and 14% improved, whereas 41% of clients with functional scores (n = 52) at the study’s inception improved. The results suggest that individual career counseling can make a difference in the lives of many clients; they also highlight the importance of further outcome research that accounts for possible variability in clients’ responses to career counseling.  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