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1.
The generalized half-normal (GHN) distribution and progressive type-II censoring are considered in this article for studying some statistical inferences of constant-stress accelerated life testing. The EM algorithm is considered to calculate the maximum likelihood estimates. Fisher information matrix is formed depending on the missing information law and it is utilized for structuring the asymptomatic confidence intervals. Further, interval estimation is discussed through bootstrap intervals. The Tierney and Kadane method, importance sampling procedure and Metropolis-Hastings algorithm are utilized to compute Bayesian estimates. Furthermore, predictive estimates for censored data and the related prediction intervals are obtained. We consider three optimality criteria to find out the optimal stress level. A real data set is used to illustrate the importance of GHN distribution as an alternative lifetime model for well-known distributions. Finally, a simulation study is provided with discussion.  相似文献   
2.
This article estimates the value of a statistical life (VSL) for Chile under the hedonic wage method while accounting for individual risk preferences. Two alternative measures of risk aversion are used. First, risk aversion is directly measured using survey measures of preferences over hypothetical gambles, and second, over observed individual behaviors that may proxy for risk preferences, such as smoking status, are used. I reconcile the results with a theoretical model of economic behavior that predicts how the wage‐risk tradeoff changes as risk aversion differs across individuals. The VSL estimates range between 0.61 and 8.68 million dollars. The results using smoking behavior as a proxy for risk attitudes are consistent with previous findings. However, directly measuring risk aversion corrects the wage‐risk tradeoff estimation bias in the opposite direction. The results are robust to other observed measures of risk aversion such as drinking behavior and stock investments. Results suggest that, consistent with the literature that connects smoking behavior with labor market outcomes, smoking status could be capturing poor health productivity effect in addition to purely risk preferences.  相似文献   
3.
挖掘特定产品的需求模式无法从整体掌握该类产品的市场特征;短生命周期体验品因缺乏历史销售数据,并且销售总量波动性极大,尤其需要从整体掌握销售总量与产品属性间关系的需求特征规律,但又难以挖掘,亟待提出适用于该类产品的需求特征模式挖掘方法。基于按销售总量分区后各区的需求特征的规律性,提出了一种按销售总量分区、以已有产品介绍集和销售总量为源信息、适用于新产品开发前使用、融合内容分析和关联分析的短生命周期体验品需求特征模式挖掘方法。该方法包括基于内容分析法的产品属性挖掘方法和基于关联分析的产品属性关系模式挖掘方法。前者可以得到较全面的产品属性;后者能够构建不同销售总量区间内产品集的属性关系模式,得到各区间的产品属性关系网,获得高销售总量区间具备,但中、低区间不具备的属性关系模式,从而获得需求特征模式。通过不断更新产品介绍集和销售总量并迭代挖掘,该方法能够动态挖掘需求特征模式。最后利用2013至2016年国产犯罪和爱情类电影数据验证了该方法的可行性,并得到了这两类电影的产品属性及近年的需求特征模式,可用于指导这两类电影的创作。  相似文献   
4.
为了削弱传统零售商在渠道博弈中的垄断地位,制造商尝试建立在线渠道与零售商展开竞争。本文在考虑消费者低碳偏好的基础上,又将消费者的渠道偏好进行区分,通过不同决策模式的对比及数值算例分析,寻求低碳供应链最优的减排边界。研究表明:1分散决策时,制造商的低碳决策会受消费者渠道偏好的影响;集中决策时,制造商的低碳决策保持不变。2不同决策模式的减排边界由渠道偏好决定,渠道偏好较大时,分散决策的减排边界更高;渠道偏好较低时,集中决策的减排边界更高;渠道偏好中立时,两者的减排边界相同。3制造商可以通过升级低碳技术、实行低碳化管理等方式降低减排成本,同时通过低碳产品认证、广告宣传等方式提高消费者对低碳产品的认可程度。  相似文献   
5.
This paper focuses on how immigrant women experience and negotiate their everyday life with children prior to and after leaving a violent partner. Twenty‐three women staying at domestic violence and abuse shelters with their children were interviewed about their experiences with assistance services and their everyday life with their children. At the time of the interviews, most of the women were legally separated or divorced and were either living in or in touch daily with shelters. In this paper, we look at some of the challenges that women face when exposed to violence in a relationship that involves children. Being exposed to violence from a partner raises a number of economic, practical, and emotional concerns, both prior to and after leaving. For the mothers in our study, maintaining a regular routine is key to making the children feel safe in an unpredictable setting. For many, economic dependence on the partner is replaced with economic dependence on assistance services after leaving the partner. Services must recognize that providing help to mothers who have left a violent partner constitutes more than just practical support but is crucial for mothers' ability to re‐establish a predictable everyday life with their children.  相似文献   
6.
《1844年经济学哲学手稿》和《神圣家族》都是马克思主义创始人早期思想的代表性著作,二者都把“生活”作为重要概念进行论述。从作为经济学哲学概念到作为社会批判概念,马克思主义创始人对“生活”的认识经历了从对物质生产活动的重视到对无产阶级普遍贫困生活的揭露,从分析“生产生活”的异化到对“非人性”生活的批判,从“生活的手段”到消灭“非人性的生活条件”的思想历程。人类的历史是人类生活发展的历史。解决人的美好生活如何实现的问题,在马克思恩格斯的生活思想中居于核心地位,这对当今中国具有重要的理论指导价值。中国特色社会主义进入新时代,从开启一种全新文明的生活形态的高度来理解新时代的美好生活,才能准确把握我国社会主要矛盾变化的深刻意义。  相似文献   
7.
Abstract

Objective: Attention deficit hyperactivity disorder (ADHD) negatively influences various aspects of life such as social relations, adaptive skills, and occupation. In addition, many university students experience sleep problems, academic failure, and low quality of life (QOL). We investigated the relationship among ADHD symptoms, sleep quality, and QOL of college students, and identified the factors related to their QOL. Participants and Methods: Using a survey questionnaire, data were collected from 195 students from March–May 2017. Results: QOL of students was related to ADHD symptoms and sleep quality. Factors significantly associated with better QOL were fewer ADHD symptoms, good sleep quality, male sex, high academic performance, and high economic status. The explanatory power of these variables on QOL was 32.0%. Conclusion: To improve the QOL of college students, a multifaceted approach that includes assessment of ADHD symptoms and sleep quality is needed.  相似文献   
8.
To improve access to education in Ecuador, state actors encourage parents and youth to think of girls’ emotional bonds to family as potential barriers to schooling. High schoolgirls and their mothers respond by synchronising their institutional and family responsibilities with the emotional norms of age grades such as ‘student youth’ and ‘mother’. Girls dedicated to embodying national progress find themselves trying to delay strong emotional commitments to family until after they have completed their schooling. Examining their construction as emotional suspects reveals the stakes of age expectations for female citizens in Ecuador.  相似文献   
9.
生命本身是一个随机事件,并不具有高尚的意义。进化的结果使人类可通过工作、家庭和人际关系等给予自己的生命以意义感。当我们的生活方式使脑内奖赏系统获得刺激,就会带来生命具有意义的感受,这种感受给人带来更好的生存机会。生存的欲望是一切生物体最具特征的属性,一些精神疾病患者缺乏这种欲望。自杀主要发生于精神疾病患者,它并非是基于自由意志的行为。抗精神病治疗和适当的社会交往可以预防自杀。由于不同个体有着不同的大脑,人们的生活方式就应该去适应各自大脑的特征。只要人们的生活方式不对他人造成过多的伤害,政府就应该允许和保护人们自由地按照各自的方式生活。  相似文献   
10.
As parental ages at birth continue to rise, concerns about the effects of fertility postponement on offspring are increasing. Due to reproductive ageing, advanced parental ages have been associated with negative health outcomes for offspring, including decreased longevity. The literature, however, has neglected to examine the potential benefits of being born at a later date. Secular declines in mortality mean that later birth cohorts are living longer. We analyse mortality over ages 30–74 among 1.9 million Swedish men and women born 1938–60, and use a sibling comparison design that accounts for all time-invariant factors shared by the siblings. When incorporating cohort improvements in mortality, we find that those born to older mothers do not suffer any significant mortality disadvantage, and that those born to older fathers have lower mortality. These findings are likely to be explained by secular declines in mortality counterbalancing the negative effects of reproductive ageing.  相似文献   
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