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1.
We introduce a new type of heavy‐tailed distribution, the normal reciprocal inverse Gaussian distribution (NRIG), to the GARCH and Glosten‐Jagannathan‐Runkle (1993) GARCH models, and compare its empirical performance with two other popular types of heavy‐tailed distribution, the Student's t distribution and the normal inverse Gaussian distribution (NIG), using a variety of asset return series. Our results illustrate that there is no overwhelmingly dominant distribution in fitting the data under the GARCH framework, although the NRIG distribution performs slightly better than the other two types of distribution. For market indexes series, it is important to introduce both GJR‐terms and the NRIG distribution to improve the models’ performance, but it is ambiguous for individual stock prices series. Our results also show the GJR‐GARCH NRIG model has practical advantages in quantitative risk management. Finally, the convergence of numerical solutions in maximum‐likelihood estimation of GARCH and GJR‐GARCH models with the three types of heavy‐tailed distribution is investigated.  相似文献   
2.
Aims: The EINSTEIN-Extension trial (EINSTEIN-EXT) found that continued treatment with rivaroxaban for an additional 6 or 12 months (vs placebo) after 6–12 months of initial anticoagulation significantly reduced the risk of recurrent venous thromboembolism (VTE) with a small non-significant increased risk of major bleeding (none fatal or in critical site). This study aimed to compare total healthcare cost between rivaroxaban and placebo, based on the EINSTEIN-EXT event rates.

Methods: Total healthcare cost was calculated as the sum of treatment and clinical event costs from a US managed care perspective. Treatment duration and event rates were obtained from the EINSTEIN-EXT study. Adjustment on treatment duration was made by assuming a 10% non-adherence rate. Drug costs were based on wholesale acquisition costs. Cost estimates for clinical events (i.e. recurrent deep vein thrombosis [DVT], recurrent pulmonary embolism, major bleeding, clinically relevant non-major bleeding) were determined from the literature. Results were examined over a ±20% range of each cost component and over 95% confidence intervals (CIs) of event rate differences in deterministic (one-way) and probabilistic sensitivity analyses (PSA).

Results: Total healthcare cost was $1,454 lower for rivaroxaban-treated (vs placebo-treated) patients in the base-case, with a lower clinical event cost fully offsetting drug cost. The cost savings of recurrent DVT alone (–$3,102) was greater than drug cost ($2,723). Total healthcare cost remained lower for rivaroxaban in the majority (73%) of PSA (cost difference [95% CI]?=?–$1,454 [–$2,396, $1,231]).

Limitations: This study was conducted over the 1-year observation period of the EINSTEIN-EXT trial, which limited “real-world” applicability and examination of long-term economic impact. Assumptions on drug and clinical event costs were US-based and, thus, not applicable to other healthcare systems.

Conclusions: Total healthcare costs were estimated to be lower for patients continuing rivaroxaban therapy compared to those receiving placebo in VTE patients who had completed 6–12 months of VTE treatment.  相似文献   
3.
Objective: To review, summarize, and analyze both similarities and differences of pharmacoeconomic (PE) guidelines, to enable researchers to access their characteristics and the current state of PE guidelines; furthermore, to learn which methodological issues still remain contested and to promote the methodological development of PE guidelines.

Materials and methods: The authors performed a search for PE guidelines using PubMed, the Cochrane library database, and the websites of the International Society for Pharmacoeconomics and Outcomes Research. Information of each guideline was extracted using a pre-designed extraction template, which included 22 aspects; the guidelines were summarized in the forms of charts, and their characteristics have been described.

Results: A total of 40 PE guidelines were studied. The most common methodological issues include the types of analysis, sources for effectiveness, use of quality-adjusted life-years (QALYs) to measure outcomes, and use of incremental cost effectiveness ratios to present results. The majority of the guidelines preferred a cost utility analysis with outcomes expressed in terms of QALYs. Most of the guidelines preferred meta-analysis or meta-analysis of the randomized controlled trials, and required a systematic review of all evidence. Issues that varied most in the guidelines were the choice of the comparator, recommended costs to be included, methods related to indirect cost calculations, methods of sensitivity analysis, and discounting rate.

Conclusion: A comparison of these guidelines revealed that a number of differences exist among them in several key aspects, and some critical methodological issues still exist, for which no best solution is available. Furthermore, efforts need to be made to develop harmonious methods for the PE, and to improve the transferability of the outcomes of PE evaluations.  相似文献   
4.
基于引力模型,结合社会网络分析法的凝聚子群分析,对31个省(区、市)的创新产出空间联系进行探究,研究发现:我国省域创新产出空间联系主要集中于京津冀和长三角一带,呈现出严重的分布不均状况,具有较强的区域集中性和空间依赖性;北京、天津、上海、浙江、江苏作为区域创新产出引力较强的节点省(区、市),对周边区域的创新产出具有较强的辐射作用;总体来看,省域创新产出空间联系并没有形成贯穿东西南北的交叉网状结构,中心省(区、市)数量较少且分布不均,辐射范围有限。基于此,提出加大区域创新投入、减少区域创新产出联系的政策性障碍、营造区域创新产出联系的良好环境等政策建议。  相似文献   
5.
We compare real-time density forecasts for the euro area using three DSGE models. The benchmark is the Smets and Wouters model, and its forecasts of real GDP growth and inflation are compared with those from two extensions. The first adds financial frictions and expands the observables to include a measure of the external finance premium. The second allows for the extensive labor-market margin and adds the unemployment rate to the observables. The main question that we address is whether these extensions improve the density forecasts of real GDP and inflation and their joint forecasts up to an eight-quarter horizon. We find that adding financial frictions leads to a deterioration in the forecasts, with the exception of longer-term inflation forecasts and the period around the Great Recession. The labor market extension improves the medium- to longer-term real GDP growth and shorter- to medium-term inflation forecasts weakly compared with the benchmark model.  相似文献   
6.
We believe that what most authors have in mind when referring to the “most redistributive country” is a tax and transfer schedule that is most redistributive across all pre-tax and transfer income distributions. In order to measure each country's tax and transfer redistribution according to the same baseline, we suggest using the transplant-and-compare method of Dardanoni and Lambert (2002, Journal of Public Economics 86, 99–122) to establish a common base. The redistributive effects of countries’ tax and transfer schedules are illustrated by employing microdata on eight countries from the Luxembourg Income Study (LIS). Of these eight countries, Finland is found to be the most redistributive country, according to the common base method.  相似文献   
7.
目的:比较传统玻璃蒸馏瓶蒸馏装置、二氧化硫测定仪、自动凯氏定氮仪3种仪器测定食品中二氧化硫的效果及适用性,为设备选型提供参考.方法:选取番薯干、咸菜、香菇干,分别用上述3种蒸馏装置测定样品中的二氧化硫含量,分析测定结果和过程控制.结果:使用3种不同蒸馏仪器测定结果无显著性差异,两次独立测定结果的绝对差值小于算术平均值的10%,回收率均在85%~95%.结论:二氧化硫测定仪自动化程度高,安全性高,基本可以替代传统玻璃蒸馏瓶蒸馏,实现大部分食品的批量检测,对于香菇干等蒸馏过程易倒吸食品,可采用自动凯氏定氮仪检测,提高实验的准确性和可靠性.  相似文献   
8.
Large-scale land deals have attracted considerable attention for various reasons, including their implications for local livelihoods. While some view the phenomena as a development opportunity, encompassing improvement in the livelihoods of local people, others argue that it is an impoverishing scheme. Ethiopia ranks among the top in terms of the size of land leased out over the last decade. Land is a major resource of state control and investment in Ethiopia. As the foundation of their livelihoods and identity, it is simultaneously a vital resource for the local people. Highlighting the importance of land for local livelihoods and state-society relations and employing a political-ecological approach, this paper analyzes the outcomes of two land lease cases for the local people in Bakko Tibbe district of Oromia, Ethiopia. The findings show that the land leases induced a significant decline in local people’s access to land, resulting in a significant reduction in crop production and livestock husbandry. The land leases also dismantled longstanding land-based social relations in both production systems. Based on empirical evidence from specific localities and contextualizing the local livelihood dynamics within broader political-economic conditions, this study contributes to the ongoing debate on livelihood impacts of global land deals.  相似文献   
9.
This study investigated whether variations in personality traits are related to board game usage patterns and attitudes, and whether such associations are expressed differently across countries that reflect different cultural orientations and values. A cross-sectional online survey was distributed among 486 Danes, Germans, and Americans, whose personalities were assessed through the NEO-FFI questionnaire. Participants also indicated their liking levels, attitudes, and playing frequency of board games. Results showed significant associations between personality traits and board game-related attitudes and habits. However, these associations were moderated by culture and primarily predicted responses among Danish participants, but not their American or German counterparts. These findings have important implications for the board-game industry, a multi-billion-dollar market worldwide. Furthermore, findings can shed light on how to better personalize and design board games according to personality traits and culture-specific preferences, which should have a significant impact on the user experience and ultimately increase sales.  相似文献   
10.
[目的]蛋鸡养殖场规模化养殖与生态环境保护协调发展问题是蛋鸡养殖业可持续发展过程中面临的关键性问题,测度我国大、中、小3种规模下不同省份蛋鸡养殖场的环境全要素生产率,并从时间、地区两个维度对蛋鸡养殖场的环境全要素生产率进行比较。[方法]利用2004—2016年不同养殖规模蛋鸡养殖场的投入和产出数据,文章基于SBM函数的Malmquist Luengerber(ML)指数方法,对蛋鸡养殖场环境全要素生产率进行分解,将其分解为技术进步指数、效率改进指数。[结果](1)蛋鸡养殖场环境全要素生产率整体呈现下降趋势,同时与蛋鸡养殖规模呈反比,蛋鸡养殖场规模越大,蛋鸡养殖环境生产率越小。(2)蛋鸡养殖场效率存在效率改善,但养殖技术进步率相对较低,尤其是对小规模养殖场而言,改善空间更明显; (3)蛋鸡养殖环境全要素生产率区域差异较为明显,整体来看,蛋鸡养殖主产区环境全要素生产率高于非主产区。[结论]加强蛋鸡产业科技创新水平以及公共服务设施的投入,提高养殖户的废弃物无害化处理能力,推行蛋鸡养殖的规模化和标准化发展,进一步改善养殖效率,以促进蛋鸡养殖规模化和生态环境保护协调发展。  相似文献   
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