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991.
In this paper, a comparison between the life distribution of a new unit with that of a used unit in the increasing convex order is made leading to a new class of life distributions which we call “new better than used in convex ordering of second order”. This class includes as subclasses the NBU and the NBUC and is a subclass of the NBUCA class. Preservation properties under convolution, random maxima, mixing and formation of coherent structures are established. Stochastic comparisons of the excess lifetime when the inter-arrival times belong to the NBUC(2) class are developed. Some applications of Poisson shock models and a test of exponentiality against NBUC(2) alternative are presented.  相似文献   
992.
In this paper, we consider the laws of large numbers for NSD random variables satisfying Pareto-type distributions with infinite means. Based on the Pareto-Zipf distributions, some weak laws of large numbers for weighted sums of NSD random variables are obtained. Meanwhile, we show that a weak law for Pareto-Zipf distributions cannot be extended to a strong law. Furthermore, based on the two tailed Pareto distribution, a strong law of large numbers for weighed NSD random variables is presented. Our results extend the corresponding earlier ones.  相似文献   
993.
The exponentially weighted moving average (EWMA) chart is often designed assuming the process parameters are known. In practice, the parameters are rarely known and need to be estimated from Phase I samples. Different Phase I samples are used when practitioners construct their own control chart's limits, which leads to the “Phase I between-practitioners” variability in the in-control average run length (ARL) of control charts. The standard deviation of the ARL (SDARL) is a good alternative to quantify this variability in control charts. Based on the SDARL metric, the performance of the EWMA median chart with estimated parameters is investigated in this paper. Some recommendations are given based on the SDARL metric. The results show that the EWMA median chart requires a much larger amount of Phase I data in order to reduce the variation in the in-control ARL up to a reasonable level. Due to the limitation of the amount of the Phase I data, the suggested EWMA median chart is designed with the bootstrap method which provides a good balance between the in-control and out-of-control ARL values.  相似文献   
994.
货币当局资产负债表是分析央行行为与货币政策执行情况的一个重要报表。我国货币当局资产负债表科目随着经济金融结构的演变经历了多次调整,本文梳理了我国货币当局资产负债表结构及其演变过程,重新编制1999-2018年的年度可比货币当局资产负债表,通过解析各科目余额及其结构的动态变化特征,揭示统计数据背后的经济逻辑与政策实践、以及重要资产负债科目间的勾稽关系。研究发现:外汇占款和对其他存款性公司的债权是我国货币当局投放基础货币的主要渠道。过去20年中,两种渠道此消彼长反映出我国基础货币投放方式和货币政策调控方式的两次重要转变与创新。在外汇占款大幅增长时期,货币当局曾通过频繁提高法定存款准备金率和发行央行票据回笼过剩流动性。随着国际收支顺差收窄和国内经济由高速增长向高质量发展转变,公开市场操作和创新型再贷款工具将成为货币当局主动投放基础货币的重要渠道。  相似文献   
995.
利用2003-2016年中国280个地级市的数据,分别测算了产业协同集聚指数、资本错配和劳动力错配指数,采用差分GMM方法考察产业协同集聚对资源错配的影响。结果发现:产业协同集聚的提高,会显著降低资本错配和劳动力错配指数;分地区的回归发现,东部地区产业协同集聚改善了资本错配,对劳动力错配负向作用不显著,中部地区产业协同集聚会改善资本错配,但会恶化劳动力错配,西部地区产业协同集聚则加剧了资本错配,但可以缓解劳动力错配情况。进一步作用机制分析表明,产业协同集聚水平的提高,会显著提高金融业的专业化分工,进而改善资本错配,同时会提高劳动力成本,改善劳动力错配。文章的政策含义是通过产业协同集聚,可以提高金融业的专业化分工和劳动力成本,进而缓解资本和劳动力的错配,提高经济效率,促进经济增长。  相似文献   
996.
In a Poisson process, it is well-known that the forward and backward recurrence times at a given time point t are independent random variables. In a renewal process, although the joint distribution of these quantities is known (asymptotically), it seems that very few results regarding their covariance function exist. In the present paper, we study this covariance and, in particular, we state both necessary and sufficient conditions for it to be positive, zero or negative in terms of reliability classifications and the coefficient of variation of the underlying inter-renewal and the associated equilibrium distribution. Our results apply either for an ordinary renewal process in the steady state or for a stationary process.  相似文献   
997.
As part of the process of examining their theory of change (TOC) and reflecting on grant making activity, one Midwestern foundation employed a multipronged strategy to assess 209 community-based mental health grants across seven years of funding. This article details the evaluation approach, which comprised these areas of the TOC: grantees’ use of evidence-based interventions, cultural competency, quality improvement, community collaboration, and use of integrated care. Inductive analyses identified grantees’ use of innovative practices, trauma-informed care, and use of validated instruments. In an iterative exercise spanning multiple years, the foundation and researchers found ways to gather information about community capacity and impact while simultaneously minimizing grantee data collection/reporting burden. Findings revealed that community agencies were improving in their uptake of evidence-based interventions and use of validated instruments. Community grantee use of trauma informed care also improved over the study period. Grantee desire to collaborate and coordinate services within the community was also strong. The research also revealed that in multiple domains (such as technology and non-profit operating costs) grantees needed support in building agency capacity. These findings shed light on which aspects of the foundation’s TOC were being addressed through funding, and which areas of the community needed additional support.  相似文献   
998.
This article analyses the facilitating and hindering factors that have affected the implementation of gender equality interventions in research and innovation in Europe. It applies the evaluation framework developed in the EFFORTI project that recognizes the complexity of evaluating gender equality interventions in R&I, the importance of factoring in context to any sound evaluation as well as the need to distinguish between the design and implementation of interventions in evaluations. It is based on the analysis of 19 empirical case studies carried out throughout Europe and focuses on those structural and procedural factors that have either facilitated or hindered the implementation process of these interventions. Findings include how the governance framework; top-management commitment; bottom-up participation; framing synergies with other initiatives, strategies for tackling resistance; resources; sustainability of actions; gender competence, experience and knowledge and transparency, targets, standards and monitoring; and accessible data and information all contributed to the successful implementation of the interventions.  相似文献   
999.
Multisite evaluation has been cited as a strategy for building knowledge about a program's success and enhancing evaluation capacity and evaluation use. Even so, the extent to which data from these efforts are made available to individual project participants varies. This article describes a community-created multisite evaluation that was designed to overcome this limitation. Based on the negotiated centralized evaluation model and implemented within the context of a community of practice, the EvalFest community-created multisite evaluation has used shared measures to collect data from 30,000 participants from partner sites across the community over three years. This article describes the design characteristics of the community-created multisite approach, and presents results related to partners’ evaluation use that demonstrate the early success of this method. We conclude by considering how this strategy might be applied to other sectors.  相似文献   
1000.
This study examines when and why employees engage in external communicative behaviors during the periods of a corporate crisis. Combining a cross-situational factor (i.e., pre-crisis relationship quality) and a situational factor (i.e., crisis-specific perceptions), this study segments internal publics to understand employees’ motivations of becoming advocates for or adversaries of their organization. The results of an online survey demonstrated that employees’ pre-crisis relationship to their organization plays a critical role in encouraging them to advocate for their company; meanwhile, their crisis-perception—whether they feel fewer constraints in solving a crisis—is more likely to make them share negative information externally. Segmented groups of employees with high levels of both relationship and activeness are most likely to engage in both positive and negative external communication behaviors. Theoretical and practical implications for public relations and internal crisis communication are suggested.  相似文献   
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