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21.
Advance selling is a marketing strategy commonly used by online retailers to increase sales by exploiting consumer valuation uncertainty. Recently, some online retailers have started to allow refunds on products sold in advance. On the one hand this reduces the net advance sales, but on the other hand it allows a higher advance sales price. This research is the first to explore the overall effect of allowing a refund on profits from advance sales, identifying conditions where advance selling with or without refunds (or no advance selling at all) is best. We analytically compare the profits of three advance selling strategies: none, without refund, and with refund. We show that selling in advance and allowing a refund is optimal for products with a relatively small profit margin and small strategic market size, and that the added profit can be considerable. Our results guide managers in selecting the right advance selling strategy. To facilitate this, we graphically display, based on the two dimensions of regular profit margin and strategic market size, under what conditions the different strategies are optimal.  相似文献   
22.
This study proposes an integrated simulation approach, which consists of a microscopic traffic simulation model, a vehicle dynamics model, and an emission estimation model, in order to estimate emissions based on more reliable vehicle performance measures. The vehicle performance measures such as engine power and engine speed significantly relate to the amount of emissions, and road curvatures and inclinations are the core inputs affecting these vehicle performance measures. Therefore, providing reliable vehicle performance measures reflecting the road geometric attributes is critical for a reliable emission estimation. This study proposes to use the microscopic traffic simulation model for generating vehicle trajectories, which is advantageous in modeling various traffic situations, and the vehicle dynamics model for producing the vehicle performance measures based on the vehicle trajectories. Finally, the outputs from the vehicle dynamics model are fed into the emission estimation model to compute emission measures. This study conducted a case-study using two road sections, one is a hypothesized road section, including various curvatures and inclinations with regular variations, and the other is a Kesselberg road section, which is an actual geometry in Bayern, Germany. The emission measures are estimated in these case-study road sections using both an existing simulation approach and the proposed integrated simulation approach. The difference between these two emission estimation approaches is discussed in terms of the emission measures, including fuel consumption, nitrogen oxides, and particulate matters.  相似文献   
23.
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   
24.
我国秸秆综合利用面临形势与对策研究   总被引:1,自引:0,他引:1  
[目的]为加快推动秸秆资源化利用,促进农业绿色发展。[方法]文章在系统梳理我国秸秆综合利用政策文件、相关文献的基础上,全面分析了我国农作物秸秆禁烧和综合利用的发展阶段,提出了秸秆利用面临的形势和存在的主要问题。[结果]我国秸秆综合利用从时间序列上,可以划分为起步阶段、强力推进阶段和攻坚阶段。城镇化的快速推进、农村能源结构的调整、农业供给侧结构性改革的实施、农作物季节矛盾突出等,成为秸秆综合利用面临的新形势、新挑战。当前推进秸秆综合利用存在四大方面问题:秸秆还田成本较高,区域技术规范和技术适宜性缺乏;受"成本地板"和"价格天花板"双重挤压,秸秆产业化利用发展困难;秸秆收储运成本高,技术装备水平低,用地、运输问题尚未解决,收储运体系建设不健全;关键性政策工具尚未破题,缺乏普惠性、针对性的资金扶持。[结论]针对形势与问题,提出了推进秸秆资源化利用的4条对策建议:开展县域秸秆全量化利用、分区施策确定秸秆利用方向、加强政策工具集成创设、扩大试点示范引导。  相似文献   
25.
In this study we use the recently mandated risk factor disclosure to examine the spillover effect of the Securities and Exchange Commission (SEC) review of qualitative corporate disclosure. We find that firms not receiving any comment letter (“No‐letter Firms”) modify their subsequent year's disclosures to a larger extent if the SEC has commented on the risk factor disclosure of (i) the industry leader, (ii) a close rival, or (iii) numerous industry peers. We refer to this effect as “spillover.” Further, we find that after SEC comments on the industry leader's disclosure, No‐letter Firms also provide more firm‐specific disclosures in the subsequent year. The increased disclosure specificity reduces these firms’ likelihood of receiving SEC risk disclosure comments on their new filings. Our evidence suggests an indirect effect of the SEC review of qualitative disclosure.  相似文献   
26.
[目的]利用遥感蒸散数据快速评价农田年度灌溉水平,及时获取基本农田建设成效,为农田灌溉设施分区建设提供参考。[方法]以黑龙江省海伦市为研究区,MOD16蒸散产品为数据源,计算有效灌溉量、灌溉需水量和作物缺水指数,分别对研究区2013年的旱地和水田灌溉水平进行评价,并将评价结果与农田水利设施作用分值图进行叠加分析,在此基础上进行基本农田灌溉设施建设分区。[结果]2013年海伦市耕地灌溉水平整体较高,区域间建设水平差别较大,可划分为4个级别。其中1级和2级灌溉水平的地块面积比例可达78.06%,地域分布上看,北部、西部、中部乡镇灌溉水平较高,东南部乡镇灌溉水平相对较低。叠加得出8种组合类型,分为设施修建型、设施提升型和设施维护型3种分区类型。[结论]研究为高标准农田建设提供了更详细的农田灌溉水平评价方法和更具差别化的农田灌溉设施建设策略。  相似文献   
27.
The quantification of operational risk has become an important issue as a result of the new capital charges required by the Basel Capital Accord (Basel II) to cover the potential losses of this type of risk. In this paper, we investigate second-order approximation of operational risk quantified with spectral risk measures (OpSRMs) within the theory of second-order regular variation (2RV) and second-order subexponentiality. The result shows that asymptotically two cases (the fast convergence case and the slow convergence) arise depending on the range of the second-order parameter. We also show that the second-order approximation under 2RV is asymptotically equivalent to the slow convergence case. A number of Monte Carlo simulations for a range of empirically relevant frequency and severity distributions are employed to illustrate the performance of our second-order results. The simulation results indicate that our second-order approximations tend to reduce the estimation errors to a great degree, especially for the fast convergence case, and are able to capture the sub-extremal behavior of OpSRMs better than the first-order approximation. Our asymptotic results have implications for the regulation of financial institutions, and may provide further insights into the measurement and management of operational risk.  相似文献   
28.
29.
Unlike most of the literature that examines the relationship between corporate philanthropy and financial performance, this study investigates the mechanisms through which corporate socially responsible behaviors produce financial outcomes. We propose that corporate philanthropy improves corporate competitiveness by eliciting positive responses from stakeholders, who assess a firm’s philanthropic contribution in relation to its rivals to determine what level of support they wish to provide to the firm. We predict that a firm’s philanthropy relative to its rivals has a positive effect on its product market competitiveness, and that this positive effect is moderated by three conditions that influence stakeholder response: stakeholder attention to philanthropy, its perceived legitimacy, and expectations of corporate giving. Our predictions are generally supported by our analyses. Overall, this paper shows that strategic philanthropy has a quantitative dimension, and firms obtain the market competitiveness associated with corporate philanthropy by integrating their rivals’ positions into their decision making.  相似文献   
30.
“坚持总体国家安全观”是党的十九大报告关于国家发展战略的基本要求。以习近平同志为核心的党中央对应急管理工作高度重视,积极改革应急管理机构设置,加快构建“全灾种、全方位、全过程”的国家综合应急管理体制。同时,财政作为国家治理的基础和重要支柱,财政治理现代化是应急管理体制现代化的先决条件之一。目前我国应急管理的理论研究较少嵌入财政治理机制的影响。本文梳理了国内外应急管理的相关治理理论,结合我国应急管理体制改革的现实需求,分析了当前我国应急管理中财政治理的现状,构建了我国应急管理中财政治理的政策体系模型,并提出了相应财税政策建议。  相似文献   
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