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11.
ABSTRACT

In this paper, we are interested in nonparametric inference issues for stochastic damping hamiltonian systems under the fluctuation-dissipation condition. This condition relates the magnitude of the dissipative term and the magnitude of the random term. The precise balance between the drift term which removes energy in average and the stochastic term provided by the fluctuation-dissipation relation insures that the canonical measure is preserved by the dynamics. In this framework, it is possible to give an explicit construction of a Lyapunov function and thus to prove exponential ergodicity. Then, we consider various estimation procedures and provide also a numerical section, where simulations are conducted.  相似文献   
12.
This article takes a first look at the distribution of returns to education for people with disabilities, a particularly disadvantaged group whose labor market performances have not been well studied or documented. Using a nonparametric approach, we uncover significant heterogeneity in the returns to education for these workers, which is drastically masked by conventional parametric methods. Based on these estimates, we construct the Sharpe ratio of human capital investment (taking into account its substantial risk), and our results corroborate the claimed importance of human capital in improving these workers’ wages. Our stochastic dominance tests show that the returns to education for workers with disabilities, as a group, may have been affected more adversely in the most recent recession, relative to their non-disabled counterparts.  相似文献   
13.
Drawing upon both heuristic‐ and threat‐based approaches, we sought to examine whether perceived similarity with injury‐prone people and perceived control over injury occurrence would directly contribute to perceived risk and whether these variables would mediate the previous injury–perceived risk relationship. Judokas (n = 207) reported the number of injuries experienced in the past year and then completed measures of perceived similarity, perceived control, and injury risk perception. Analyses revealed that perceived similarity and perceived control directly contributed to perceived risk of injury; only perceived similarity acted as a partial mediator of the injury–perceived risk relationship. These findings are discussed in relation to the potential influence of the sport context, which universally involves the acceptance of a high risk of injury.  相似文献   
14.
水果和蔬菜是为人体提供矿物质、维生素、膳食纤维等营养元素的重要农产品,我国居民饮食中普遍存在着能量相对过剩、果蔬摄入量不足的问题。以人体膳食均衡为研究视角,研究我国果蔬消费趋势和结构优化问题,结果表明:按照当前的消费趋势发展,我国居民营养摄入不足与过剩同在的问题依然无法得到解决;我国政府在制定水果和蔬菜战略布局的决策中,应综合考虑人体的膳食营养均衡和未来市场营养需求,以实现我国果蔬产业布局优化;消费者在进行水果和蔬菜消费购买行为时,应在营养膳食均衡的基础上进行合理消费。  相似文献   
15.
1995年以来,欧盟不断加强对个人数据的保护力度,被遗忘权由此成为欧盟个人数据保护立法上的一个重要概念,历经三个阶段,日趋受到合理限制.在国际上,各国在被遗忘权问题上,存在一般被遗忘权和特殊被遗忘权的立法分野,前者以欧盟最为典型,后者包括美国等国家.鉴于被遗忘权在实践层面并不能产生实质性效果,反倒给互联网产业创新发展带来负担,且既有规范体系已经足够为个人数据和隐私提供充分保护,因此我国未来在制定相关立法时,没必要引入甚至扩大被遗忘权,反而应当从数据最小化、 通过设计保护隐私等层面做出努力,并且应当积极参与国际网络治理规则的制定.  相似文献   
16.
法律翻译是法律运行机制下的语言转换,面临法律与语言体系的双重制约。对等则是法律翻译的重中之重,这就意味着翻译的主要任务是解决源语与目标语之间的意义分歧。法律是一种符号,而构成该符号的法律语言发挥着特定的功能。这个特定功能是指通过探寻法律符号意义的过程,理解法律对社会产生的影响和效果。基于符号学语义三角提出的翻译语义三角可以为法律翻译中的精确对等提供理论基础。然而现实中法律翻译往往受到话语环境和话语使用群体的制约,通过具体的实证研究,可以得出两个结论:在同一法律体系内,可以通过翻译语义三角实现法律翻译精确对等;借助从社会符号学视角出发的语义参考方案、法定意义与社会意义的区分、语言元功能等策略,可以理解法律翻译的复杂性。  相似文献   
17.
This article presents an evaluation framework developed to assess the first-level effects of introducing the Standard Days Method (SDM) in Peru Ministry of Health clinics. Four questions are asked: 1) To what extent do providers routinely achieve SDM service delivery standards? 2) Is the time invested in SDM delivery consistent with program norms? 3) How does SDM delivery compare with delivery of established methods? and 4) How does SDM introduction affect delivery of established methods? A study at 62 clinics demonstrated the framework's usefulness. The Standard Days Method introduction had positive overall effects on the quality of care but provider training needed adjustments.  相似文献   
18.
Networks of ambient monitoring stations are used to monitor environmental pollution fields such as those for acid rain and air pollution. Such stations provide regular measurements of pollutant concentrations. The networks are established for a variety of purposes at various times so often several stations measuring different subsets of pollutant concentrations can be found in compact geographical regions. The problem of statistically combining these disparate information sources into a single 'network' then arises. Capitalizing on the efficiencies so achieved can then lead to the secondary problem of extending this network. The subject of this paper is a set of 31 air pollution monitoring stations in southern Ontario. Each of these regularly measures a particular subset of ionic sulphate, sulphite, nitrite and ozone. However, this subset varies from station to station. For example only two stations measure all four. Some measure just one. We describe a Bayesian framework for integrating the measurements of these stations to yield a spatial predictive distribution for unmonitored sites and unmeasured concentrations at existing stations. Furthermore we show how this network can be extended by using an entropy maximization criterion. The methods assume that the multivariate response field being measured has a joint Gaussian distribution conditional on its mean and covariance function. A conjugate prior is used for these parameters, some of its hyperparameters being fitted empirically.  相似文献   
19.
This paper develops a novel and efficient algorithm for Bayesian inference in inverse Gamma stochastic volatility models. It is shown that by conditioning on auxiliary variables, it is possible to sample all the volatilities jointly directly from their posterior conditional density, using simple and easy to draw from distributions. Furthermore, this paper develops a generalized inverse gamma process with more flexible tails in the distribution of volatilities, which still allows for simple and efficient calculations. Using several macroeconomic and financial datasets, it is shown that the inverse gamma and generalized inverse gamma processes can greatly outperform the commonly used log normal volatility processes with Student’s t errors or jumps in the mean equation.  相似文献   
20.
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   
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