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211.
Tim Benson 《Journal of medical economics》2017,20(2):107-113
Background: QALYs are widely used in health economic evaluation, but remain controversial, largely because they do not reflect how many people behave in practice. This paper presents a new conceptual model (Load Model) and illustrates it in comparison with the QALY model.Methods: Load is the average annual weight attributed to morbidity and mortality over a defined period, using weightings based on preference judgements. Morbidity Load is attributed to states of illness, according to their perceived severity. When people are in full health, Load is zero (no morbidity). Death is treated as an event with negative consequences, incurred in the year following death. Deaths may be weighted equally, with a fixed negative weight such as ?100, or differ according to the context of death. After death, Load is zero. In a worked example, we use the standard gamble method to obtain a weighting for an illness state, for both Load and QALY models. A judge is indifferent between certainty of 1.5 years’ illness followed by death, or a 50/50 chance of 1.5 years’ full health or 1-year illness, each followed by death. The weightings calculated are applied to a hypothetical life, 72 years in full health followed by 3 years with illness then death, using both models. Three other hypothetical outcomes are also compared.Results: For an example life, the relative size of the morbidity component compared with the mortality component is much higher in the Load model than in the QALY model. When comparing alternative outcomes, there are also substantial differences between the two models.Conclusions: In the Load model the weight of morbidity, relative to mortality, is very different from that in the QALY model. Given the role of the QALYs in economic evaluation, the implications of an alternative, which generates very different results, warrant further exploration. 相似文献
212.
It is well known that intra-industry trade and cross-border production networks have promoted economic growth and regional integration in East Asia. However, regional supply and production chains may have been formed differently across industries, reflecting different degrees and a different scope of regional economic linkages at an industry level. This paper makes a threefold contribution. First, to assess industry-level differences, this study adopts the generalized purchasing power parity (G-PPP) model using industry-specific producer prices. Second, the momentum threshold autoregressive (M-TAR) model is employed to allow for possible nonlinearity arising from the dynamic nature of regional economic growth and development. Third, the Granger causality test is also conducted to assess whether regional economies have autonomously integrated. The empirical results reveal that economic integration has progressed more autonomously in the electrical industry, as well as in the transportation equipment industry, as China and the ASEAN countries have become the final destination markets for finished products in these two industries. 相似文献
213.
本文建立了同时测定欧盟高关注物质(SVHC)第23批新增的4种物质[1-乙烯基咪唑、-甲基咪唑、4-羟基苯甲酸丁酯、双(乙酰丙酮酸)二丁基锡的气相色谱质谱联用仪(GC-MS)]的检测方法。将样品用二氯甲烷超声后,采用选择离子监控模式(SIM)进行分析样品中的待测物。实验结果表明,4种物质在50 mg/L范围内线性关系良好,线性相关系数为0.995以上;样品加标回收率为94%110%,相对标准偏差(RSD)小于7%;方法检出限分别为2 mg/kg、10mg/kg、0.8 mg/kg、0.6 mg/kg,解决了欧盟新增加的4种SVHC测试问题。 相似文献
214.
《The British Accounting Review》2021,53(5):100923
Drawing on the board capital literature, we use a panel data design to investigate the effect of boardroom nationality on the profitability and solvency of property-casualty insurers operating in the United Kingdom (UK). We find that boardroom nationality influences corporate outcomes depending on the financial aspects being measured. For example, North American directors are linked with profitable outcomes, while European directors tend to be associated with better solvency. This reflects differences between the shareholder value corporate culture in North America and stakeholder approaches more common in Europe. Our results could help insurers, regulators, and others (e.g., investors) to better understand the potential performance implications of the appointment of directors of different nationality. 相似文献
215.
Landscape assessment methods have traditionally valued the landscape through a panel of experts with little or no participation of the population. However, after the adoption of the European Landscape Convention (ELC), the perception and the participation of the population has played an increasingly important role in landscape evaluation and planning. In this regard, the goal of this paper is to develop a model able to evaluate and integrate both the objective and subjective landscape factors into a new concept: the Preservability. This model, as well as selecting and classifying the landscape attributes according to the bio-geographic features of the study area i.e., Ricote Valley (Region of Murcia, Spain), includes two online surveys: one to assess the populatiońs landscape preferences and the other to obtain the specific weight of each objective and subjective landscape factor from a panel of experts. These landscape factors were incorporated into a GIS. To obtain the best model, the Preservability was assessed from three different approaches: objective, objective-weighted and weighted. The final results demonstrate how the Preservability weighted method returns different thresholds appropriate to the landscape attributes, the population’s perceptual preference and the protected areas. The different thresholds allows for priority areas to be identified for protection, as well as the adoption of appropriate management and planning strategies according to the landscapes characteristics, current state and uniqueness. 相似文献
216.
UxDMA算法是一种高效的集中式算法,是用于时分多址、频分多址和码分多址信道分配的统一算法。在UxDMA的基础上,利用多波束天线的多波束形成能力,针对低时延定向ad hoc网络提出了一种集中式调度算法——CLSM(Centralized Low-delay Scheduling Algorithm Based on Multi-beam Antennas)。CLSM通过不同时延等级限制的报文来比较着色后发送链路的优先级,优先选择高优先级链路传输。通过仿真验证了CLSM的性能:与UxDMA相比,该算法在多时延限制的发送端调度中表现出了更好的吞吐量和时延性能。 相似文献
217.
The lack of knowledge of how resilience management supports enterprise system (ES) projects accounts for the failure of firms to leverage their investments in costly ES implementations. Using a structured-pragmatic-situational (SPS) case study research approach, this paper reports on an investigation into the resilience management of a large utility company as it implemented an ES upgrade. Drawing on the literature and on the case study findings, we developed a process-based resilience management framework that involves three strategies (developing situation awareness, demystifying threats, and executing restoration plans) and four organisational capabilities that transform resilience management concepts into practices. We identified the crucial phases of ES upgrade implementation and developed indicators for how different strategies and capabilities of resilience management can assist managers at different stages of an ES upgrade. This research advances the state of existing knowledge by providing specific and verifiable propositions for attaining a state of resilience, the knowledge being grounded in the empirical reality of a case study. Moreover, the framework offers ES practitioners a roadmap to better identify appropriate responses and levels of preparedness. 相似文献
218.
Prior research has mostly examined consumer attitudes toward online services/retailing in general and a few researchers have addressed consumer experiences with online food delivery (OFD) services. The purpose of this study is to examine the structural relationship between convenience motivation, post-usage usefulness, hedonic motivation, price saving orientation, time saving orientation, prior online purchase experience, consumer attitude and behavioral intention towards OFD services. The study proposes an integrative theoretical research model based on the Contingency Framework and Extended Model of IT Continuance. 224 valid questionnaires were collected to empirically test the research model using the partial least square (PLS) path modeling approach. The results imply that the proposed hypotheses were supported, except for the relationship between prior online purchase experience and post-usage usefulness. Practical implications and limitations are discussed. 相似文献
219.
在激烈的市场竞争下,军工科研企业面临如何有效地降低研发成本、提高研发效率、提升研发质量,从而实现规模化、产业化发展等问题。集成产品研发(Integrated Product Development, IPD)由IBM首先成功实践,可以帮助企业快速、低成本、准确地开发出满足市场的产品,快速从以项目为核心、解决产品有无问题的阶段,向以平台和共享为核心的产业化发展阶段跨越。从军工企业科研面临的问题,研究了IPD军工科研企业如何借鉴IPD思想,本地化建立符合军工业务特点的研发体系,提出了基于IPD的研发体系建设目标、建设内容和实施步骤。 相似文献
220.
A common procedure in economics is to estimate long-run effects from models with lagged dependent variables. For example, macro panel studies frequently are concerned with estimating the long-run impacts of fiscal policy, international aid, or foreign investment.Our analysis points out the hazards of this practice. We use Monte Carlo experiments to demonstrate that estimating long-run impacts from dynamic models produces unreliable results.Biases can be substantial, sample ranges very wide, and hypothesis tests can be rendered useless in realistic data environments. There are three reasons for this poor performance. First, OLS estimates of the coefficient of a lagged dependent variable are downwardly biased in finite samples. Second, small biases in the estimate of the lagged, dependent variable coefficient are magnified in the calculation of long-run effects. And third, and perhaps most importantly, the statistical distribution associated with estimates of the LRP is complicated, heavy-tailed, and difficult to use for hypothesis testing. While many of the underlying problems have been long-known in the literature, the continued widespread use of the associated empirical procedures suggests that researchers are unaware of the extent and severity of the estimation problems. This study aims to illustrate their practical importance for applied research. 相似文献