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1.
This study explores the conditional version of the capital asset pricing model on sentiment to provide a behavioural intuition behind the value premium and market mispricing. We find betas (β) and the market risk premium to vary over time across different sentiment indices and portfolios. More importantly, the state β derived from this sentiment-scaled model provides a behavioural explanation of the value premium and a set of anomalies driven by mispricing. Different from the static β–return relation that gives a flat security market line, we document upward security market lines when plotting portfolio returns against their state βs and portfolios with higher state βs earn higher returns.  相似文献   
2.
盛朝迅 《改革》2020,(2):5-19
“十四五”时期是国际经济秩序重塑的关键期、新一轮科技革命和产业变革由孕育发展向形成高潮的关键过渡期、我国跨过高收入门槛的关键期和改革攻坚的关键时期,也是我国新旧动能接续转换的关键时期。加快新旧动能转换对于促进经济持续稳定健康增长、抢占新一轮科技革命机遇和实现高质量发展等意义重大,是我国转换发展方式、调整经济结构、建设现代化经济体系和实现体制机制转型的重要途径。必须深化对新旧动能转换内涵和特征的认识,厘清思路,明确新旧动能转换重点;深化体制机制改革,激发新旧动能转换活力;培育主体,做优做强一批新旧动能转换领军企业和优质中小企业;加快集群建设,形成一批新旧动能转换高地;创新优化要素支撑,夯实新旧动能转换基础;提升对外开放水平,拓展新旧动能转换空间。  相似文献   
3.
Improving access is a priority in the offshore wind sector, driven by the opportunity to increase revenues, reduce costs, and improve safety at operational wind farms. This paper describes a novel method for producing probabilistic forecasts of safety-critical access conditions during crew transfers. Methods of generating density forecasts of significant wave height and peak wave period are developed and evaluated. It is found that boosted semi-parametric models outperform those estimated via maximum likelihood, as well as a non-parametric approach. Scenario forecasts of sea-state variables are generated and used as inputs to a data-driven vessel motion model, based on telemetry recorded during 700 crew transfers. This enables the production of probabilistic access forecasts of vessel motion during crew transfer up to 5 days ahead. The above methodology is implemented on a case study at a wind farm off the east coast of the UK.  相似文献   
4.
Renewable energy is worldwide seen as a key element necessary to address climate change. However, finding socially acceptable locations for renewable energy facilities and the accompanying infrastructure increasingly often faces fierce opposition. This paper quantifies the landscape externalities of renewable energies employing a choice experiment. In addition, it is investigated how accounting for non-compensatory choice behavior, i.e. attribute cut-offs, affects welfare measures and subsequently policy recommendations. The empirical application is Germany where we conducted a nationwide survey on the development of renewable energies. We first show that cut-off elicitation questions prior to the choice experiment at least partially influence preferences. We further find that most participants state cut-off levels for attributes. Many are, however, at the same time willing to violate the self-imposed thresholds when choosing among the alternatives. To account for this effect, stated cut-offs are incorporated into a mixed logit model following the soft cut-off approach. Model results indicate substantial taste heterogeneity in preferences and in the use of cutoffs. Also, welfare estimates are substantially affected. We conclude that welfare changes from renewable energy development could be strongly underestimated when cut-offs are ignored.  相似文献   
5.
闽侯县闲置农地生态安全评价研究   总被引:1,自引:0,他引:1  
[目的]根据闽侯县农用地闲置情况,结合当地社会经济及生态环境发展情况,深入分析闽侯县闲置农地的生态安全发展水平。[方法]建立闽侯县闲置农地生态安全评价指标体系,分别从农村垃圾处理点数量、财政支农资金、外部进入农村投资、农业生产总值、种粮补贴、自然灾害、农业技术水平、农村生物的多样性程度、农村家庭收入结构、农村生态补偿金额、农地的整理规模及环保支出占GDP比重共确定12个指标进行深入研究,运用普通最小二乘法对设计的多元线性回归模型进行回归,进一步对闽侯县闲置农地的生态安全水平进行评价。[结果]农村垃圾处理点数量、财政支农资金、种粮补贴、环保支出占GDP比重、生态补偿金额、生物多样性程度对闽侯县闲置农地生态安全水平起到促进作用,呈正相关趋势;自然灾害则与闲置农地生态安全水平呈负相关趋势。[结论]整体看来,闽侯县闲置农地的生态安全水平主要受到当地经济、环境及生态基础三大因素的影响。  相似文献   
6.
Although enterprises in the informal food sector require energy to transform, cook and process food, energy-use patterns in this sector are not well understood by policymakers and the local-level authorities who regulate their trading activities. This paper reviews relevant literature and presents empirical data collected in Rwanda, Senegal and South Africa on the use of traditional and modern energy sources by informal food sector operators. Our sample includes male- and female-operated enterprises in the urban centres of three African countries where the informal food sector is important, not only for providing the convenience of affordable and readily prepared meals, but also as a source of income for women and men in developing countries. Multiple fuel-use and energy-stacking strategies are common among informal food enterprises and policy needs to acknowledge this if it is to intervene in ways that will benefit both enterprises and regulators.  相似文献   
7.
Empowering women farmers to participate in agricultural research is a key strategy for sustainable agricultural development. Women empowerment has the potential to improve their roles in agricultural production while enhancing nutrition and food security. Although new agricultural development policies are focusing on improving women engagement in agriculture, there is limited literature on women empowerment in relation to agricultural research. This study used mixed methods to analyse women farmers’ participation in four stages of the agricultural research process – design, testing, dissemination, monitoring and evaluation. Two hundred and thirty individual interviews with women farmers and 16 focus group discussions with men and women farmers were conducted in four Woredas (districts) of Ethiopia. Quantitative data were analysed using binary and multivariate probit models. Qualitative data were analysed using line-by-line coding. The results showed that several empowerment indicator variables significantly (p?≤?.001) influenced women’s participation in different stages of agricultural research. Specifically, input in production decisions, autonomy in plot management, membership to farmer groups, and ability to speak in public enhanced women’s participation in different stages, in addition to access to information and extension services, education and land size. Cultural norms hindered women’s empowerment and engagement in research. To foster sustainable agriculture development, it’s important to integrate holistic and proactive gender perspectives into research strategies to increase women’s participation in farmer research groups, access information and knowledge, have voice and challenge constraining cultural norms and traditions.  相似文献   
8.
Reducing dependence on fossil fuels by decreasing energy consumption is a common environmental policy. One mechanism used to achieve this is to encourage increased energy efficiency. However, improving efficiency may have an opposing effect and cause an increase in energy consumption if the intensity of use changes. This phenomenon is known as the rebound effect. We estimate direct rebound effects for energy use in Australia based on both aggregate residential energy use data and on household energy expenditure data. Our approach implements a new methodology developed by Hunt and Ryan (2014, Catching on the rebound: Why price elasticities are generally inappropriate measures of rebound effects. Surrey Energy Economics Discussion Paper Series SEEDS 148; 2015, Energy Economics 50, 273) that explicitly relates energy service use with energy source demand and directly incorporates measures of efficiency changes. The results indicate that the rebound effect is relatively high for energy use by Australian households. Due to the unique nature of our household data set, we can examine the influence of demographic and housing characteristics. We find that low‐income households and households with vulnerable members have the largest rebound effects. The relatively large rebound effects found here suggest that consumers gain from efficiency by improved energy services, and thus, policy targeting energy efficiency is not likely to be successful at reducing energy consumption.  相似文献   
9.
深入学习习近平在中国共产党第十九次全国代表大会上的报告,在考察20世纪以来的12次金融危机的基础上,对系统性金融风险发生的根源进行了研究,并结合我国当前系统性金融风险面临的形势,提出了防范系统性金融风险的对策建议。研究表明,将过去100多年引发金融危机的系统性金融风险的根源与我国当前的金融形势进行比较分析,可以发现我国面临的系统性金融风险形势十分严峻,必须在党的领导下,采取打击金融腐败、适当收紧货币政策、完善金融监管体系、维护币值稳定、加强金融科技监管等相关政策来防止系统金融风险的发生。  相似文献   
10.
Using three waves (2008/09, 2010/11, 2012/13) of the Tanzanian National Panel Survey, this study investigates the impact of maize price shocks on household food security. Between 2008/09 and 2012/13, calorie intake stagnated for urban households, yet sharply deteriorated for rural households. The latter was driven by a significant decline in the consumption of the major staple maize which showed strongest price hikes among all major food items. Fixed-effects regressions indicate a clear negative relationship between maize prices and average household energy intake. Almost all population groups were found to be negatively affected by maize price shocks, with rural landless households being the most vulnerable group. In particular, a 50 percent rise in maize prices decreases caloric intake for rural (urban) households on average by 4.4 (5.4) percent, and for rural landless households by 12.6 percent. Results further indicate that subsistence agriculture can act as an effective strategy to insure against food price volatility.  相似文献   
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