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91.
The structure of a firm-commitment Seasoned Equity Offering (SEO) resembles a put-option underwritten by an investment bank syndicate (Smith, 1977). Employing implied volatilities from issuers’ stock options as a direct forward-looking measure, this paper examines the impact of expected price risk around SEO issue dates on the direct cost of issuing equity. Using a comprehensive sample of 1208 SEOs between 1996 and 2009, we find issuers with higher option implied volatilities raise less external equity capital and pay higher investment bank fees in the stock market, ceteris paribus. The effect of implied volatility on the investment bank fees is stronger for larger issuers with lower pre-SEO abnormal realized stock volatilities, and for SEOs with higher expected price pressures around issue dates. These relationships are robust to adjustments for correlations among control variables, sample selection bias and also simultaneous determination of offer size and SEO fees.  相似文献   
92.
The experience from the global financial crisis has raised serious concerns about the accuracy of standard risk measures as tools for the quantification of extreme downward risks. A key reason for this is that risk measures are subject to a model risk due, e.g. to specification and estimation uncertainty. While regulators have proposed that financial institutions assess the model risk, there is no accepted approach for computing such a risk. We propose a remedy for this by a general framework for the computation of risk measures robust to model risk by empirically adjusting the imperfect risk forecasts by outcomes from backtesting frameworks, considering the desirable quality of VaR models such as the frequency, independence and magnitude of violations. We also provide a fair comparison between the main risk models using the same metric that corresponds to model risk required corrections.  相似文献   
93.
换乘所产生的附加费用,如时间和票价等,导致配流影响因素产生变化,如果沿用传统方式将降低预测精度和可靠性。通过引入换乘次数和方式等因子计算出行等待、乘车、换乘及风险评估预留时间等,定义广义出行费用与计算方法;建立双层规划模型求解最优票价,最后通过算例分析弹性出行需求、换乘费用、票价之间的关系。计算结果表明,换乘费用对出行需求的影响小于票价优化对出行需求的影响,优化票价随换乘费用增加而加速降低,为公共交通票价优化提供研究依据。  相似文献   
94.
为使铁路调度集中系统更好地满足运输组织需求,提升运输组织效率,阐述我国铁路调度集中系统运用现状,针对存在的系统功能区域化割裂、系统部署灵活性较低、系统建设和运用成本高等问题,结合铁路调度集中系统运用特点,提出基于云计算技术的铁路调度集中系统架构方案,将铁路调度集中系统部署在由云平台资源层、云平台服务层、云平台用户与接口层组成的云平台上,按需分配系统资源并动态扩充系统边界,提升系统资源利用率,提高业务协调性和计划编制的统一性,减轻运输人员的劳动强度,保障铁路运输生产的安全稳定。  相似文献   
95.
In this paper, we examine the stock market integration process amongst 17 Economic and Monetary Union (EMU) countries from January 2002 to June 2013 over a normal period as well as for the Global Financial Crisis (GFC) and Eurozone Debt Crisis (EDC) periods. We classify the economies in three groups (A, B and C) based on their GDP to examine whether the economic size influences financial integration. Seven indicators are used for the purpose, namely, beta convergence, sigma convergence, variance ratio, asymmetric DCC, dynamic cointegration, market synchronisation measure and common components approach. The results suggest that large-sized EMU economies (termed as Group A) exhibit strong stock market integration. Moderate integration is observed for middle-sized EMU economies with old membership (termed as Group B). Small-sized economies (termed as Group C) economies seemed to be least integrated within the EMU stock market system. The findings further suggest presence of contagion effects as one moves from normal to crisis periods, which are specifically stronger for more integrated economies of Group A. We recommend institutional, regulatory and other policy reforms for Group B and especially Group C to achieve higher level of integration.  相似文献   
96.
Lin Zhao 《Quantitative Finance》2017,17(11):1759-1782
We apply utility indifference pricing to solve a contingent claim problem, valuing a connected pair of gas fields where the underlying process is not standard Geometric Brownian Motion and the assumption of complete markets is not fulfilled. First, empirical data are often characterized by time-varying volatility and fat tails; therefore, we use Gaussian generalized autoregressive score (GAS) and GARCH models, extending them to Student’s t-GARCH and t-GAS. Second, an important risk (reservoir size) is not hedgeable. As a result, markets are incomplete which makes preference free pricing impossible and thus standard option pricing methodology inapplicable. Therefore, we parametrize the investor’s risk preference and use utility indifference pricing techniques. We use Least Squares Monte Carlo simulations as a dimension reduction technique in solving the resulting stochastic dynamic programming problems. Moreover, an investor often only has an approximate idea of the true probabilistic model underlying variables, making model ambiguity a relevant problem. We show empirically how model ambiguity affects project values, and importantly, how option values change as model ambiguity gets resolved in later phases of the projects. We show that traditional valuation approaches will consistently underestimate the value of project flexibility and in general lead to overly conservative investment decisions in the presence of time-dependent stochastic structures.  相似文献   
97.
阮健弘  刘西  叶欢 《金融研究》2015,482(8):18-33
近年来,我国居民部门杠杆率的快速上升引起社会各界关注。本文使用货币信贷和城镇储户调查数据,对我国居民部门杠杆率和偿债能力现状进行了分析,并运用各省住户贷款数据计算各省的居民杠杆率,使用面板数据模型对居民杠杆率上升的原因进行了实证分析。结果表明,房价的快速上涨和住房销售的增长都对居民部门杠杆率的上升有显著正向影响,其中房价上涨的影响程度更大。此外,金融发展水平和老年人抚养比对居民杠杆率有正向影响,少年人抚养比对居民杠杆率有负向影响。  相似文献   
98.
深圳国际低碳城应对发展面临的创新、资金筹集和合作创新等需求,构建了一体化营城的模式,通过完善低碳城管理体制,探索构建多方合作及利益共享机制;通过发挥综合运营平台优势,提供全方位、全过程的专业服务;通过推进资源、资产、资本综合管理,创新多元化的筹资机制,在低碳城建设运营中取得了良好成效,并在创新新型园区建设运营、正确处理政府和企业在发展新兴产业中的关系方面,提供了有益的借鉴。  相似文献   
99.
Objective:

To carry out a cost–utility analysis comparing initial treatment of patients with overactive bladder (OAB) with solifenacin 5?mg/day versus either trospium 20?mg twice a day or trospium 60?mg/day from the perspective of the German National Health Service.

Methods:

A decision analytic model with a 3 month cycle was developed to follow a cohort of OAB patients treated with either solifenacin or trospium during a 1 year period. Costs and utilities were accumulated as patients transitioned through the four cycles in the model. Some of the solifenacin patients were titrated from 5?mg to 10?mg/day at 3 months. Utility values were obtained from the published literature and pad use was based on a US resource utilization study. Adherence rates for individual treatments were derived from a United Kingdom general practitioner database review. The change in the mean number of urgency urinary incontinence episodes/day from after 12 weeks was the main outcome measure. Baseline effectiveness values for solifenacin and trospium were calculated using the Poisson distribution. Patients who failed second-line therapy were referred to a specialist visit. Results were expressed in terms of incremental cost–utility ratios.

Results:

Total annual costs for solifenacin, trospium 20?mg and trospium 60?mg were €970.01, €860.05 and €875.05 respectively. Drug use represented 43%, 28% and 29% of total costs and pad use varied between 45% and 57%. Differences between cumulative utilities were small but favored solifenacin (0.6857 vs. 0.6802 to 0.6800). The baseline incremental cost–effectiveness ratio ranged from €16,657 to €19,893 per QALY.

Limitations:

The difference in cumulative utility favoring solifenacin was small (0.0055–0.0057 QALYs). A small absolute change in the cumulative utilities can have a marked impact on the overall incremental cost-effectiveness ratios (ICERs) and care should be taken when interpreting the results.

Conclusion:

Solifenacin would appear to be cost-effective with an ICER of no more than €20,000/QALY. However, small differences in utility between the alternatives means that the results are sensitive to adjustments in the values of the assigned utilities, effectiveness and discontinuation rates.  相似文献   
100.
陈寒松  贾竣云  田震 《南方经济》2019,38(10):78-89
农业创业者如何通过整合与管理资源与能力,设计新颖型商业模式创造更多价值,是实现乡村振兴战略的关键措施。文章基于资源编排、商业模式理论,以央视《致富经》栏目40个案例为样本,运用模糊集定性比较分析(fsQCA)方法,剖析资源编排、机会能力、创业学习所构成的前因变量组态对农业创业活动中商业模式设计的影响机制。研究发现,资源编排在农业创业活动中发挥不可或缺的关键作用;相较于资源结构化和资源捆绑,资源利用在新颖型商业模式设计中的作用更为突出;机会能力须与资源编排共同作用,方可实现新颖型商业模式设计;在资源编排作用缺乏时,创业学习的发挥有助于新颖型商业模式设计的形成。研究成果诠释了农业创业情境下资源编排、机会能力与创业学习对商业模式设计的影响机制,为开展农业创业活动提供指导。  相似文献   
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