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131.
Harsanyi's impartial observer must consider two types of lotteries: imaginary identity lotteries (“accidents of birth”) that she faces as herself and the real outcome lotteries (“life chances”) to be faced by the individuals she imagines becoming. If we maintain a distinction between identity and outcome lotteries, then Harsanyi‐like axioms yield generalized utilitarianism, and allow us to accommodate concerns about different individuals' risk attitudes and concerns about fairness. Requiring an impartial observer to be indifferent as to which individual should face similar risks restricts her social welfare function, but still allows her to accommodate fairness. Requiring an impartial observer to be indifferent between identity and outcome lotteries, however, forces her to ignore both fairness and different risk attitudes, and yields a new axiomatization of Harsanyi's utilitarianism.  相似文献   
132.
Masters athletes are typically older than 35 years of age and systematically train for, and compete in, organized forms of sport specifically designed for older adults. They are motivated to participate in masters sport for a wide variety of reasons. Age-related declines in endurance performance are observed across the endurance sports of running, orienteering, rowing, and swimming. These declines are curvilinear from age 35 years until approximately age 60–70 years and exponential thereafter. The decline in endurance performance appears primarily due to an age-related decrease in VO2max secondary to an age-related decrease in HRmax and possible age-related declines in stroke volume and arteriovenous oxygen difference. While performance velocity at lactate threshold decreases with age in masters endurance athletes, it appears to increase relative to VO2max while exercise economy is maintained. There also appears an age-related decrease in active muscle mass, type II muscle fiber size, and blood volume that contribute to decreased endurance performance. However, research suggests that maintenance of training intensity and volume into older age may mediate the rate of age-related decline in VO2max, stroke volume, arteriovenous oxygen difference, blood volume, and muscle mass in masters endurance athletes.  相似文献   
133.
Ghoudi, Khoudraji & Rivest [The Canadian Journal of Statistics 1998;26:187–197] showed how to test whether the dependence structure of a pair of continuous random variables is characterized by an extreme‐value copula. The test is based on a U‐statistic whose finite‐ and large‐sample variance are determined by the present authors. They propose estimates of this variance which they compare to the jackknife estimate of Ghoudi, Khoudraji & Rivest ( 1998 ) through simulations. They study the finite‐sample and asymptotic power of the test under various alternatives. They illustrate their approach using financial and geological data. The Canadian Journal of Statistics © 2009 Statistical Society of Canada  相似文献   
134.
Urban green spaces provide important ecosystem services, such as amenity, biodiversity, productivity, climate amelioration, hydrological and biogeochemical cycling. Intensively managed urban gardens can sequester carbon through vegetation growth and soil C increase, but may experience nitrous oxide (N2O) emissions and reduced soil methane (CH4) uptake from irrigation and fertiliser use. Soil atmosphere exchange of N2O, CH4 and carbon dioxide (CO2) was measured in lawn and wood chip mulched garden areas in Melbourne, Australia in winter, spring and summer under various water and fertiliser regimes. Gas exchange before and after lawn fertiliser application was measured continuously for three weeks using an automated chamber system. Applying fertiliser led to a peak N2O emission of >60 μg N m−2 h−1, but overall only weekly irrigation (10 mm) significantly increased mean soil N2O emissions above that in other treatments. Under mulch, mean soil N2O emissions (14.0 μg N m−2 h−1) were significantly smaller than from irrigated lawn (27.9 μg N m−2 h−1), whereas mean soil CH4 uptake under mulch (−30.7 μg C m−2 h−1) was significantly greater (p < 0.01) than in any lawn treatment. Lawns were either a weak CH4 sink or source. Soil C density (0–25 cm) under mulch (12.5 kg C m−2) was greater that under lawn (8.0 kg C m−2). On a carbon dioxide equivalent (CO2-e) basis, soil N2O emissions offset the benefits of soil CH4 uptake. Mulched garden areas provide greatest C sequestration potential in soil and vegetation and the smallest non-CO2 emissions, as soil CH4 uptake offsets a large fraction of soil N2O emissions. Results of this study suggest that reducing the irrigation and fertiliser application to lawns can help mitigate GHG emissions from urban garden systems, and increasing the area of mulched perennial garden beds can also provide net GHG benefits; however, this needs to be tested in other garden systems with different soil types and environmental conditions.  相似文献   
135.
ABSTRACT

This article examines IBM’s ‘Smarter Education’ program, part of its wider ‘Smarter Cities’ agenda, focusing specifically on its learning analytics applications (based on machine learning algorithms) and cognitive computing developments for education (which take inspiration from neuroscience for the design of brain-like neural networks algorithms and neurocomputational devices). The article conceptualizes the relationship between learning algorithms, neuroscience, and the new learning spaces of the city by combining the notion of programmable ‘code/space’ with ideas about the ‘social life of the brain’ to suggest that new kinds of ‘brain/code/spaces’ are being developed where the environment itself is imagined to possess brain-like functions of learning and ‘human qualities’ of cognition performed by algorithmic processes. IBM’s ambitions for education constitute a sociotechnical imaginary of a ‘cognitive classroom’ where the practices associated with data analytics and cognitive computing in the smart city are being translated into the neuropedagogic brain/code/spaces of the school, with significant consequences for how learners are to be addressed and acted upon. The IBM imaginary of Smarter Education is one significant instantiation of emerging smart cities that are to be governed by neurocomputational processes modelled on neuroscientific insights into the brain’s plasticity for learning, and part of a ‘neurofuture’ in-the-making where nonconscious algorithmic ‘computing brains’ embedded in urban space are intended to interact with human cognition and brain functioning.  相似文献   
136.
The corporate pursuit of social goals – known as Corporate Social Responsibility or ‘CSR’ – has been subject to critique on a number of grounds. However, a hitherto underexplored potential consequence of CSR has been suggested in a recent paper by C. Garsten and K. Jacobsson (‘Post‐Political Regulation: Soft Power and Post‐political Visions in Global Governance’ (2013), Critical Sociology 39: 421–37). They suggest that CSR is part of an international trend towards ‘post‐political’ governance discourses, where an emphasis on different actors’ common goals obscures conflicts of interest, subverting the open political conflict necessary for a well‐functioning democracy. This paper examines whether such post‐political discourses – including an outright denial of conflict of interest – can be found within the alcohol and gambling industries, where conflicts of interest are likely to be particularly acute given the addictive nature of the goods/services in question. Based on interviews with CSR professionals in these industries in Italy, the UK, and at EU‐level, we do indeed find evidence of a post‐political discourse. In these discourses, alcohol/gambling industry staff deny potential conflicts of interest on the basis that any small benefits from sales to a small number of addicts are seen to be outweighed by the reputational damage that addicts cause. Crucially, however, this coexists with another, less post‐political discourse, where addictions CSR professionals emphasize ‘common ground’ as a basis for CSR, while accepting some instances of possible conflict of interest. Here interviewees make considerable efforts to differentiate good (sustainable) from bad (short‐term) self‐interest in order to stress the genuineness of their own actions. We conclude the paper by considering whether CSR embedded within a ‘common ground’ discourse still hides conflicts of interests and subverts democratic debate, or overcomes the problems identified by Garsten and Jacobsson.  相似文献   
137.
Often in practice one is interested in the situation where the lifetime data are censored. Censorship is a common phenomenon frequently encountered when analyzing lifetime data due to time constraints. In this paper, the flexible Weibull distribution proposed in Bebbington et al. [A flexible Weibull extension, Reliab. Eng. Syst. Safety 92 (2007), pp. 719–726] is studied using maximum likelihood technics based on three different algorithms: Newton Raphson, Levenberg Marquardt and Trust Region reflective. The proposed parameter estimation method is introduced and proved to work from theoretical and practical point of view. On one hand, we apply a maximum likelihood estimation method using complete simulated and real data. On the other hand, we study for the first time the model using simulated and real data for type I censored samples. The estimation results are approved by a statistical test.  相似文献   
138.
吴奔  张波 《统计研究》2017,(8):109-119
在高频金融数据研究中,估计金融资产价格序列积分波动率时,往往需要考虑市场微观结构噪声与资产价格跳跃的影响.本文将市场微观结构噪声部分地表示成交易信息的参数函数,并结合资产收益序列的跳跃特征,提出资产收益的高斯混合模型.本文利用EM算法进行噪声参数估计的同时,识别资产价格的跳跃,进而提出一种新的积分波动率的估计量.本文提出的方法可以视为Li等(2016)的改进,并在模拟研究中,得到了比Li等(2016)更好的参数估计效果,且即使在跳跃幅度分布误设的情况下,也具有良好的识别跳跃的功能.在应用举例中,对比了本文方法与Lee和Mykland(2008)的跳跃发现方法,论证了本文的模型在识别跳跃方面的可靠性.  相似文献   
139.
Partial order methodologies appear as advantageous tools to disclose evaluative trends and developments for time series as, e.g., the fragile states index (FSI). The present study focuses on the variations in the 12 individual indicators of the FSI over the years 2011–2015. The FSI includes in total 178 states and the present study analyzes both the full set of states and a subset comprising only the 28 European Union states. Clear trends are observed. Thus, on a global scale the primary importance of brain drain apparently is turned into group grievance whereas on the European scale the development discloses the increased problems associated with the increasing number of refugees and migrants as well as the declining economic situation in some states. Further the study discloses a series of so-called peculiar states, i.e., states where single indicators values are markedly higher or lower than expected when comparing to the “main stream” of indicator values for the states studied. In all cases the findings were substantiated and verified by available literature.  相似文献   
140.
VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Despite the benefits of volunteering to the individual, organization and community, the retention of volunteers within...  相似文献   
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