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1.
Variations in the economic recovery rate across the United States have led to even greater chasms that separate the employed, unemployed, and underemployed (DeSilver, 2017 ). Therefore, understanding and supporting the career development of future generations is critical—especially for those who live outside the context of social privilege. The authors examined the applicability of the integrative contextual model of career development (ICM; Lapan, 2004 ) to a sample of 220 adolescents (129 boys, 91 girls) from a high‐poverty urban area. Results indicated that a canonical variate comprising foundational ICM skills (e.g., career exploration, goal setting) predicted a variate composed of ICM outcomes (e.g., self‐efficacy, vocational identity), thus supporting the usefulness of the ICM framework for this population. The skill of setting viable career goals was an especially strong predictor of outcomes. Implications for career counseling with adolescents living in high‐poverty urban areas and directions for future research are discussed.  相似文献   
2.
In this article, Six Sigma zone control charts (SSZCCs) are proposed for world class organizations. The transition probabilities are obtained using the Markov chain approach. The Average Run Length (ARL) values are then presented. The ARL performance of the proposed SSZCCs and the standard Six Sigma control chart (SSCC) without zones or run rules is studied. The ARL performance of these charts is then compared with those of the other standard zone control charts (ZCCs), the modified ZCC and the traditional Shewhart control chart (SCC) with common run rules. As expected, it is shown that the proposed SSZCC outperforms the standard SSCC without zones or run rules for process shifts of any magnitude. When compared to the other standard ZCCs and the Shewhart chart with common run rules, it is observed that the proposed SSZCCs have much higher false alarm rates for smaller shifts and hence they prevent unwanted process disturbances. The application of the proposed SSZCC is illustrated using a real time example.  相似文献   
3.
For many environmental processes, recent studies have shown that the dependence strength is decreasing when quantile levels increase. This implies that the popular max‐stable models are inadequate to capture the rate of joint tail decay, and to estimate joint extremal probabilities beyond observed levels. We here develop a more flexible modeling framework based on the class of max‐infinitely divisible processes, which extend max‐stable processes while retaining dependence properties that are natural for maxima. We propose two parametric constructions for max‐infinitely divisible models, which relax the max‐stability property but remain close to some popular max‐stable models obtained as special cases. The first model considers maxima over a finite, random number of independent observations, while the second model generalizes the spectral representation of max‐stable processes. Inference is performed using a pairwise likelihood. We illustrate the benefits of our new modeling framework on Dutch wind gust maxima calculated over different time units. Results strongly suggest that our proposed models outperform other natural models, such as the Student‐t copula process and its max‐stable limit, even for large block sizes.  相似文献   
4.
The use of the term ‘high conflict’ to describe a wide range of family dynamics after separation and divorce has increased significantly over the years. At the moment, no consensus on the definition of high conflict exists. Lack of definitional clarity hinders the ability for legal and mental health professionals to assess, identify, and effectively intervene with this population. Based on a rapid evidence assessment of 65 empirically based social science studies relevant to high conflict, this article positions high-conflict separation and divorce using an ecological transactional model to better understand risk factors and indicators associated with these families. Authors propose a more comprehensive definition that captures the complexity and interactions of various risk factors and indicators on multiple levels. Positioning high-conflict families using an ecological model identifies several points of intervention professionals can use and the fundamental need for collaboration among stakeholders for effective intervention.  相似文献   
5.
The purpose of acceptance sampling is to develop decision rules to accept or reject production lots based on sample data. When testing is destructive or expensive, dependent sampling procedures cumulate results from several preceding lots. This chaining of past lot results reduces the required size of the samples. A large part of these procedures only chain past lot results when defects are found in the current sample. However, such selective use of past lot results only achieves a limited reduction of sample sizes. In this article, a modified approach for chaining past lot results is proposed that is less selective in its use of quality history and, as a result, requires a smaller sample size than the one required for commonly used dependent sampling procedures, such as multiple dependent sampling plans and chain sampling plans of Dodge. The proposed plans are applicable for inspection by attributes and inspection by variables. Several properties of their operating characteristic-curves are derived, and search procedures are given to select such modified chain sampling plans by using the two-point method.  相似文献   
6.
本文首先比较了三种目前主流的共跳检验方法:基于LM检验的共跳检验、BLT共跳检验和FHLL共跳检验,结果表明,三种方法在识别共跳数量上差距明显,但三者结果的重合部分基本属于市场暴涨暴跌行情,说明共跳识别对市场剧烈波动的聚集性较为敏感。基于跳跃、共跳存在的聚集性问题,本文将Hawkes过程引入跳跃和共跳的研究,构建了基于Hawkes过程的因子模型,结果显示,基于Hawkes因子模型的MJ统计量、CJ统计量和实证数据的拟合程度较好,表明因子模型能够更好地描述跳跃和共跳的聚集性。  相似文献   
7.
2018年3月,日本发布新的《高等学校学习指导要领》。这是日本自第二次世界大战后70多年来,对高中课程最大规模的一次修订,体现了日本高中教育发展的新趋势,标志着日本从此告别“宽松教育”而走向“生存能力”教育。由“历史综合”“日本史探究”“世界史探究”组成的新高中历史课程,立足“人”的发展,构建了“必修+选修、通史+专题”的课程体系,课程内容更加突出本国史与世界史的联系,课程学习倡导“主题+探究”的学习方式。日本高中历史课程的内容设置及特点启示我们,高中历史课程编制应加强中国史与世界史的横向关联,课程内容应体现探究性学习要求。  相似文献   
8.
在加强生态文明建设和扩大就业的背景下,环境规制能否同时实现环境保护、绿色就业与高质量发展等多重目标已成为亟待解决的重大问题。构建一种操作便捷的高质量发展评价指标,将其分解为结构效应、技术效应及规制效应,在统一框架内剖析环境规制影响高质量发展的人力资本机制,并使用联立方程空间自回归模型和省际面板数据进行检验,探究在各类人力资本因素调节下环境规制对高质量发展的非线性效应。研究发现:(1)环境规制能通过人力资本积累、产业结构升级、节能减排技术创新等途径影响高质量发展。(2)环境规制通过与人力资本溢价的动态匹配,能进一步推动产业结构升级和节能减排技术创新,助益高质量发展。(3)环境规制在人力资本因素调节下对高质量发展存在非线性影响。总体而言,人力资本因素的改善有利于充分发挥环境规制对高质量发展的倒逼效应;提升人力资本质量是当前调控人力资本因素、释放环境规制高质量发展效应的政策重点。(4)中国高质量发展存在显著为正的空间溢出效应,地方政府在环境问题中缺乏协同治理,削弱了这种空间溢出效应,因此全局层面的高质量发展有较大提升空间。充分激发环境规制的人力资本积累效应,从单纯注重人力资本“量”的扩张转向“质”的提升,实现区域协同治理,这对有效改善环境规制的高质量发展效应至关重要。  相似文献   
9.
以科斯为代表的新制度经济学为分析企业的形成、企业组织边界以及企业间关系提供了有力工具,20世纪70年代以来,网络经济概念及分析方法丰富了对企业与市场之间的组织形态--产业组织的分析.本文沿用新制度经济学分析思路,结合Mattew O.Jacson对网络基本概念的论述(Mattew O.Jacson,2002)[1],以实证分析的方法研究铁路运输产业的网络边界效率问题.  相似文献   
10.
本文以竞争力理论为指导,借鉴企业信息化测评指标体系设计的方法,从战略地位、系统应用水平、经济效益、社会效益和信息资源效益五方面考察我国铁路信息化项目效益,建立相应的评价指标体系,综合"BSC AHP FUZZY"提出铁路信息化项目效益评价的BAF法,给出有关评价步骤.  相似文献   
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