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排序方式: 共有239条查询结果,搜索用时 828 毫秒
1.
Keisuke Okada 《Economic Systems》2018,42(2):307-319
This study investigates how political regimes affect health conditions such as infant and child mortality rates and life expectancy using data from 180 countries observed between 1960 and 2013. Panel quantile regression is used to examine the effects at different intervals throughout the distribution of health outcomes. The estimation results indicate that democracy has significant positive effects on health outcomes and that its impacts are greater when health outcomes are worse. These results are robust to different democracy and health indices. The effects of different types of democracies and dictatorships are also considered, that is parliamentary, mixed (semi-presidential) and presidential democracies, and civilian, military and royal dictatorships. The parliamentary form of democracy has the largest positive impact on health outcomes at the worst quantile of health outcomes, although the difference in the impacts of the three types of democracies is not necessarily large. Furthermore, all types of dictatorships have a negative impact on health outcomes, with military dictatorship having the worst outcome when health outcomes are worse. Finally, the effects of democratization on health outcomes are significantly positive when the health outcomes are worse. 相似文献
2.
Silvia Rizzi Søren Kjærgaard Marie-Pier Bergeron Boucher Carlo Giovanni Camarda Rune Lindahl-Jacobsen James W. Vaupel 《International Journal of Forecasting》2021,37(1):95-104
Mortality forecasting has crucial implications for insurance and pension policies. A large amount of literature has proposed models to forecast mortality using cross-sectional (period) data instead of longitudinal (cohort) data. As a consequence, decisions are generally based on period life tables and summary measures such as period life expectancy, which reflect hypothetical mortality rather than the mortality actually experienced by a cohort. This study introduces a novel method to forecast cohort mortality and the cohort life expectancy of non-extinct cohorts. The intent is to complete the mortality profile of cohorts born up to 1960. The proposed method is based on the penalized composite link model for ungrouping data. The performance of the method is investigated using cohort mortality data retrieved from the Human Mortality Database for England & Wales, Sweden, and Switzerland for male and female populations. 相似文献
3.
Mangrove forests as a nature-based solution for coastal flood protection: Biophysical and ecological considerations 下载免费PDF全文
Rosanna van Hespen Zhan Hu Bas Borsje Michela De Dominicis Daniel A. Friess Svetlana Jevrejeva Maarten G. Kleinhans Maria Maza Celine E. J. van Bijsterveldt Tom Van der Stocken Bregje van Wesenbeeck Danghan Xie Tjeerd J. Bouma 《水科学与水工程》2023,16(1):1-13
Nature-based coastal protection is increasingly recognised as a potentially sustainable and cost-effective solution to reduce coastal flood risk. It uses coastal ecosystems such as mangrove forests to create resilient designs for coastal flood protection. However, to use mangroves effectively as a nature-based measure for flood risk reduction, we must understand the biophysical processes that govern risk reduction capacity through mangrove ecosystem size and structure. In this perspective, we evaluate the current state of knowledge on local physical drivers and ecological processes that determine mangrove functioning as part of a nature-based flood defence. We show that the forest properties that comprise coastal flood protection are well-known, but models cannot yet pinpoint how spatial heterogeneity of the forest structure affects the capacity for wave or surge attenuation. Overall, there is relatively good understanding of the ecological processes that drive forest structure and size, but there is a lack of knowledge on how daily bed-level dynamics link to long-term biogeomorphic forest dynamics, and on the role of combined stressors influencing forest retreat. Integrating simulation models of forest structure under changing physical (e.g. due to sea-level change) and ecological drivers with hydrodynamic attenuation models will allow for better projections of long-term natural coastal protection. 相似文献
4.
Kenshi Itaoka Aya Saito Alan Krupnick Wiktor Adamowicz Taketoshi Taniguchi 《Environmental and Resource Economics》2006,33(3):371-398
The objective of this study is to estimate willingness to pay (WTP) for the reduction of mortality risks caused by fossil
fuel (natural gas, coal and oil) versus nuclear electric power generation systems and to examine the influence of risk characteristics
involved with electric power generation on WTP. A choice experiment was conducted to achieve these objectives. The attributes
for nuclear risks in the experiment included the probability of disasters and the expected losses if a disaster occurs. We
find evidence of (i) a baseline effect (where WTP is sensitive to hypothetical versus actual baseline expected mortality);
(ii) a ‘labeling effect,’ where, surprisingly, the term ‘nuclear’ has no effect on WTP, but the term ‘fossil-fueled power
generation’ results in lower WTP; and (iii) disaster aversion, meaning that people focus on the conditional loss from a nuclear
disaster, not the probability. We also find that the WTP for reducing deaths from a nuclear disaster is about 60 times the
WTP for routine reducing fossil-fuel generation-related deaths. 相似文献
5.
Brenda Moraska Lafrancois Stephen C. Riley David S. Blehert Anne E. Ballmann 《Journal of Great Lakes research》2011,37(1):86-91
Relationships between large-scale environmental factors and the incidence of type E avian botulism outbreaks in Lake Michigan were examined from 1963 to 2008. Avian botulism outbreaks most frequently occurred in years with low mean annual water levels, and lake levels were significantly lower in outbreak years than in non-outbreak years. Mean surface water temperatures in northern Lake Michigan during the period when type E outbreaks tend to occur (July through September) were significantly higher in outbreak years than in non-outbreak years. Trends in fish populations did not strongly correlate with botulism outbreaks, although botulism outbreaks in the 1960s coincided with high alewife abundance, and recent botulism outbreaks coincided with rapidly increasing round goby abundance. Botulism outbreaks occurred cyclically, and the frequency of outbreaks did not increase over the period of record. Climate change scenarios for the Great Lakes predict lower water levels and warmer water temperatures. As a consequence, the frequency and magnitude of type E botulism outbreaks in the Great Lakes may increase. 相似文献
6.
死亡率免疫理论及其在长寿风险对冲中的应用 总被引:1,自引:0,他引:1
基于死亡率免疫理论探讨保险公司长寿风险的自然对冲问题,研究年龄、性别与保险期限等因素与保单久期和凸性之间的关系,发现保险公司欲达到长寿风险的完全对冲,其寿险业务和年金业务必须达到的最小ρ比例应该等于年金和寿险保单的久期之比,表明保险公司可以通过选择调整寿险和年金业务的比例来对冲长寿风险的影响。 相似文献
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9.
This paper examines the possible ecological and economic effects of sea lice from salmon farms on wild salmon populations and fisheries. A bioeconomic model is developed incorporating an age-structured population dynamics model of wild pink and chum salmon with mortality caused by farm-derived sea lice. Our model incorporates capture fisheries under two management policy scenarios. Results suggest that the ecological and economic effects are minor when the sea lice induced mortality rate is below 20%, while they can be severe if the mortality is greater than 30%. Sea lice have greater ecological and economic impacts on pink salmon than on chum salmon. The impact of farm lice epizootics on wild salmon is greater under a fixed exploitation rate than under a target escapement policy. As a result, a precautionary principle should be adopted, and appropriate management schemes and policy strategies should be developed to minimize these effects. 相似文献
10.
新冠肺炎疫情发生后,湖北省一直是疫情的重灾区与抗疫的焦点地区,患者死亡率远远高于全国平均水平。本文构建纳入医疗资源条件的新冠肺炎传播的SIER模型进行机制分析和模拟研究,发现改善卫生资源条件会降低疫情的死亡率。针对湖北省疫情数据,使用最小二乘方法进行实证研究后发现,无论是增加医院或者卫生系统内的床位数,还是增加医护人员数,均可显著地降低疫情死亡率。进一步通过时变效应和断点回归模型考察重大突发公共卫生事件一级响应政策效应和外援医疗团队效应,实证结果也佐证了上述推断。结合研究结论和湖北省防疫经验,本文提出先整合医院内部医疗资源,打破医院内部各科室之间分割,再整合地区内医疗卫生系统的资源,同时实施医疗系统外部资源三管齐下的医疗资源配置建议措施,以期为国内外疫情防控贡献中国智慧。 相似文献