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11.
《Risk analysis》2018,38(9):1988-2009
Harbor seals in Iliamna Lake, Alaska, are a small, isolated population, and one of only two freshwater populations of harbor seals in the world, yet little is known about their abundance or risk for extinction. Bayesian hierarchical models were used to estimate abundance and trend of this population. Observational models were developed from aerial survey and harvest data, and they included effects for time of year and time of day on survey counts. Underlying models of abundance and trend were based on a Leslie matrix model that used prior information on vital rates from the literature. We developed three scenarios for variability in the priors and used them as part of a sensitivity analysis. The models were fitted using Markov chain Monte Carlo methods. The population production rate implied by the vital rate estimates was about 5% per year, very similar to the average annual harvest rate. After a period of growth in the 1980s, the population appears to be relatively stable at around 400 individuals. A population viability analysis assessing the risk of quasi‐extinction, defined as any reduction to 50 animals or below in the next 100 years, ranged from 1% to 3%, depending on the prior scenario. Although this is moderately low risk, it does not include genetic or catastrophic environmental events, which may have occurred to the population in the past, so our results should be applied cautiously.  相似文献   
12.
We study interdependent risks in security, and shed light on the economic and policy implications of increasing security interdependence in presence of reactive attackers. We investigate the impact of potential public policy arrangements on the security of a group of interdependent organizations, namely, airports. Focusing on security expenditures and costs to society, as assessed by a social planner, to individual airports and to attackers, we first develop a game-theoretic framework, and derive explicit Nash equilibrium and socially optimal solutions in the airports network. We then conduct numerical experiments mirroring real-world cyber scenarios, to assess how a change in interdependence impact the airports' security expenditures, the overall expected costs to society, and the fairness of security financing. Our study provides insights on the economic and policy implications for the United States, Europe, and Asia.  相似文献   
13.
进化论思想与唯物史观同为近代中国影响广泛的思想。二者的传入时间接近,并且都经历了中国化的过程。随着进化论思想在现代遭到了越来越多的批判和质疑,唯物史观早期传播和发展的历程也经历了重新的审视。文章从近代思想史发展的事实出发,重新厘清两种思想的关系,并具体论证马克思的唯物史观能否从广义上归结为一种进化论的思想,以及进化论思想在中国是否经历了一个向唯物史观转变的历程。  相似文献   
14.
Bioequivalence (BE) studies are designed to show that two formulations of one drug are equivalent and they play an important role in drug development. When in a design stage, it is possible that there is a high degree of uncertainty on variability of the formulations and the actual performance of the test versus reference formulation. Therefore, an interim look may be desirable to stop the study if there is no chance of claiming BE at the end (futility), or claim BE if evidence is sufficient (efficacy), or adjust the sample size. Sequential design approaches specially for BE studies have been proposed previously in publications. We applied modification to the existing methods focusing on simplified multiplicity adjustment and futility stopping. We name our method modified sequential design for BE studies (MSDBE). Simulation results demonstrate comparable performance between MSDBE and the original published methods while MSDBE offers more transparency and better applicability. The R package MSDBE is available at https://sites.google.com/site/modsdbe/ . Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
15.
英国自都铎王朝后期至斯图亚特早期,立宪君主论或混合君主论者抵制君权神授论,坚持家庭是一个自治的、涉及臣民私人权益的小政府,受到自然法、古代宪法或神圣法的保护。《复仇者悲剧》中公爵王室言行映射詹姆士一世在《皇家礼物》中所宣扬的君权神授论,温迪斯兄弟俩及追随者的复仇隐含当时的政治抵制学说,公爵王室与温迪斯兄弟俩的对立象征君权神授论与普通法理论的对峙。温迪斯兄弟俩却以威胁新君为由被处死,司法斗争简约为复仇冲动,维权英雄陡变为暴徒,暴君化身为明君,这暴露出君权神授论的悖论性和剧作家含混的复仇伦理。  相似文献   
16.
《Social Development》2018,27(3):495-509
Parents' reactions to children's emotions shape their psychosocial outcomes. Extant research on emotion socialization primarily uses variable‐centered approaches. This study explores family patterns of maternal and paternal responses to children's sadness in relation to psychosocial outcomes in middle childhood. Fifty‐one families with 8‐ to 12‐year‐old children participated. Mothers and fathers reported their reactions to children's sadness and children's social competence and psychological adjustment. Cluster analyses revealed three family patterns: Supportive (high supportive and low non‐supportive reactions from both parents), Not Supportive (low supportive reactions from both parents), and Father Dominant (high paternal supportive and non‐supportive reactions, low maternal supportive and non‐supportive reactions). Supportive families had children with higher social competence and more internalizing symptoms whereas Father Dominant families had children with lower social competence and fewer internalizing symptoms. Not Supportive families had children with average social competence and fewer internalizing symptoms. Findings are discussed in relation to the “divergence model” which proposes that a diverse range of parental responses to children's sadness, rather than a uniformly supportive approach, may facilitate children's psychosocial adjustment.  相似文献   
17.
Abstract

In this article we develop the minimax estimation approach of general linear models to the semiparametric linear models when the parameters are simultaneously constrained by an ellipsoid and linear restrictions. Combining sample information and prior constraints the minimax estimator is obtained and compared with partially least square estimator by theoretical and simulation methods.  相似文献   
18.
While migration has been found to enhance welfare across a range of settings, most of the literature focuses on rural‐to‐urban migrant flows. Using a unique dataset from north‐western Tanzania, this article probes an important, yet overlooked, link between land markets and rural‐to‐rural migration. A mixed‐methods approach is used to discern how these two forces are intertwined in village life. Results indicate that household decisions to migrate are particularly influenced by the ease of market‐based land access in their new communities. This suggests that labour mobility may be facilitated through the development of a well‐functioning land market.  相似文献   
19.
《Risk analysis》2018,38(8):1559-1575
Security of the systems is normally interdependent in such a way that security risks of one part affect other parts and threats spread through the vulnerable links in the network. So, the risks of the systems can be mitigated through investments in the security of interconnecting links. This article takes an innovative look at the problem of security investment of nodes on their vulnerable links in a given contagious network as a game‐theoretic model that can be applied to a variety of applications including information systems. In the proposed game model, each node computes its corresponding risk based on the value of its assets, vulnerabilities, and threats to determine the optimum level of security investments on its external links respecting its limited budget. Furthermore, direct and indirect nonlinear influences of a node's security investment on the risks of other nodes are considered. The existence and uniqueness of the game's Nash equilibrium in the proposed game are also proved. Further analysis of the model in a practical case revealed that taking advantage of the investment effects of other players, perfectly rational players (i.e., those who use the utility function of the proposed game model) make more cost‐effective decisions than selfish nonrational or semirational players.  相似文献   
20.
数字货币,是一种具有财产性价值属性的电磁记录型数据。数字货币在其依存的区块链体系中所彰显的与不特定者之间的支付对价性、与法定货币之间的互换性、使用电子信息处理系统进行转移的在线转移性等特点,得以从数据说的角度,将其作为一种数据性财产权在现行法律框架内对其私法性质进行讨论。有鉴于我国民法总则已将数据纳入保护客体的范畴,数字货币作为数据之一种,理应成为一种新型法律客体,在得到法律理论支撑的基础上获得保护。  相似文献   
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