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71.
We develop an empirically based simulation study to test two types of policies designed to control systemic risk: preventive policies targeting capital requirements and mitigation policies targeting default resolution. We find that capital buffers reduce both the number of defaults and the resulting losses. The loss reduction benefit increases as the magnitude of adverse shocks becomes higher. We find that a simple branch-breakup resolution strategy reduces the loss borne by the Federal Deposit Insurance Corporation (FDIC). The mitigation effect becomes higher as the fraction of assets resolved through auctions and auction competitiveness increase.  相似文献   
72.
The explosive growth of peer-to-peer (P2P) accommodation service presents a potential transformation in the competitive landscape of accommodation sector. This research explores the market characteristics and the factors that drive and hinder the use of P2P accommodation to better explain the phenomenon of collaborative consumption in the tourism and hospitality marketplace. Using responses from travellers residing in the United States and Finland, exploratory factor analyses revealed two factors that drive the use of P2P accommodation: social appeal (desire for community and sustainability) and economic appeal (cost savings). The barriers include issues of trust, efficacy and familiarity with the system, and cost. The empirical evidence from this study suggests several managerial implications for tourism and hospitality businesses and directions for future research.  相似文献   
73.
估计和预测城市居民收入变化对家庭能源消费碳排放的影响,对城市家庭消费部门构建低碳能源供应体系,应对气候变化具有重要意义。论文首先估计了中国284个地级以上城市的家庭三类能源消费的直接碳排放量,建立了面板固定效应模型来识别城市家庭能耗碳排放增长和变化的驱动因素。研究结果表明:城市居民收入的快速增长与储蓄水平的提高对于家庭碳排放有显著影响;城市家庭收入和储蓄的增加会抑制家庭燃气碳排放的产生,但对于城市家庭用电碳排放和城市家庭采暖碳排放,则表现出显著的推动作用。此外,研究还发现了家庭碳排放的影响因素存在显著的区域异质性。  相似文献   
74.
于安琪  刘冠坤  杨超 《技术经济》2022,41(4):176-187
基于工业企业数据以及环境统计数据,构建1998-2007年面板数据实证分析出口对企业二氧化硫排放强度的影响。回归结果显示:相较于非出口企业,出口企业二氧化硫排放强度较低;企业出口强度越高时二氧化硫排放强度越低。异质性分析发现:企业所属行业以及企业所在地区差异均会对二氧化硫排放强度产生影响。具体表现为,污染密集型制造业行业中,出口企业比非出口企业更为清洁;相较于其他地区而言,东部地区企业出口对二氧化硫排放强度的降低幅度更为显著。在排除两控区环境规制因素对回归结果的影响,并且通过IV(2SLS)以及PSM-DID等方法处理内生性问题后,本文的回归结果依然稳健。机制分析表明:出口企业一方面通过提高新产品产值——R D,另一方面通过提高全要素生产率,降低了企业的二氧化硫排放强度。此外,通过对企业出口状态的改变(广延边际)和企业出口强度的改变(集约边际)的比较发现,出口企业二氧化硫排放强度低的主要驱动因素在于广延边际而非集约边际。  相似文献   
75.
目的探讨常规西药联合健脾调肝法治疗2型糖尿病胃肠功能紊乱患者的临床价值。方法选取2019年3月至2021年1月盘锦市人民医院收治的102例2型糖尿病胃肠功能紊乱患者作为研究对象,按随机数字表法分为对照组与观察组,各51例。对照组患者单纯接受常规西药治疗,观察组患者在对照组基础上接受健脾调肝法(应用以葛根、党参、茯苓、炒白术、当归、鸡内金等中药组成的健脾理气疏肝方)治疗,比较两组治疗有效率、空腹血糖(FBG)、餐后2h血糖(2h PBG)以及糖化血红蛋白(Hb A1c)、胃排空率、肠鸣音。结果观察组治疗有效率高于对照组,差异有统计学意义(P<0.05);治疗后,观察组患者FBG、2h PBG、Hb A1c水平低于对照组,差异有统计学意义(P<0.05);治疗后,观察组胃排空率、肠鸣音高于对照组,差异有统计学意义(P<0.05)。结论健脾调肝法治疗2型糖尿病胃肠功能紊乱疗效显著,应用价值较高。  相似文献   
76.
This paper examines the effect of political institutions on fiscal redistribution for a country-level panel from 1960–2010. Using data on Gini coefficients before and after government intervention, we apply a measure of effective fiscal redistribution that reflects the effect of taxes and transfers on income inequality. Our findings clearly indicate that non-democratic regimes demonstrate significantly greater direct fiscal redistribution. Subsequently, we employ fiscal data in an attempt to enlighten this puzzling empirical finding. We find that dictatorial regimes rely more heavily on cash transfers that exhibit a direct impact on net inequality and consequently on the difference between market and net inequality (i.e., effective fiscal redistribution), whereas democratic regimes devote a larger amount of resources to public inputs (health and education) that may influence market inequality but not the difference between market and net inequality per se. We argue that the driving force behind the observed differences within the pattern on government spending and effective fiscal redistribution is that democratic institutions lead survival-oriented leaders to care more for the private market, and thus to follow policies that enhance the productivity of the whole economy.  相似文献   
77.
Using detailed firm-product-year data across manufacturing industries in India, and exploiting the exogenous nature of China’s entry into the WTO in 2001, we investigate the link between the impact of import penetration from China on the product variety of Indian manufacturing firms. We find: (i) robust and significant effects of product drop, with the effect coming only from competitive pressure in the domestic market; (ii) robust evidence of product drop or ‘creative destruction’ only for firms belonging to the lower-half of the size distribution; (iii) firms drop their peripheral/marginal products and concentrate on the core ones; and (iv) the result is strongest for firms producing intermediate goods. For an average Indian manufacturing firm, a 10 percentage point increase in India’s Chinese share of imports in the domestic market reduces the product scope of firms by 1.7–4.4%. In contrast, we find positive effects on product scope when firms are importing intermediate goods. We also find evidence of significant productivity effects and within-firm factor reallocation. Our results are consistent to a battery of robustness checks and IV estimation.  相似文献   
78.
李淑锦  嵇晓佳 《技术经济》2019,38(11):117-124
立足于P2P平台,利用P2P平台个人借款人的信息建立了一套系统的信用风险评估指标体系来甄别可能违约的借款人。本文基于LightGBM(一种基于决策树的Boosting模型)和Bagging而提出一种新的LGB-BAG模型,有效结合了Boosting和Bagging的优势。结果表明,在N增大到一定程度的时候,LGB-BAG的F1均值(预测效果)要高于LightGBM和随机森林;并且LGB-BAG的F1方差也要小于其余两种模型。LGB-BAG的F1均值最高可达到0.71175,且LGB-BAG模型能够显著提高信用风险预测效率。  相似文献   
79.
Aims: Examine healthcare costs across chronic kidney disease (CKD) stages for US patients with type 2 diabetes (T2D).

Materials and methods: IQVIA Real World Data Adjudicated Claims linked electronic medical records and insurance claims from January 1, 2012 through March 31, 2017 were used for this retrospective study. Adults diagnosed with T2D and comorbid CKD were included. General linear models incorporating splines were constructed, and information from these regressions were used to inform the relationship between medical costs and CKD. Multivariable analyses controlled for patient characteristics, vital signs, general health, prior medication use, prior visit to specialists, index A1c, and year of index date.

Results: There were 6,645 individuals who met the study criteria. Results generally indicate sharp increases in annual total medical costs and non-drug medical costs in the 1?year post-period for patients with Stage 4 or 5 CKD (estimated glomerular filtration rate [eGFR]?≤?30?mL/min/1.73 m2) with each 1 point reduction in eGFR from 30 associated with an increase of $1,870 in all-cause total medical costs (p?<?0.0001) and $1,805 of all-cause non-drug medical costs (p?<?0.0001). Similarly, each point decline below 30?mL/min was associated annual cost increases of $1,701 for CKD-related total medical costs, $1,695 for CKD-related non-drug medical costs, $173 for diabetes-related medical costs, and $187 for diabetes-related non-drug medical costs (all p?<?0.0001).

Limitations: The investigation included only patients with medical insurance and laboratory test results, and results may not be generalizable to all T2D patients with CKD. The methodology allowed us to determine associations, not causation, and potential confounders, such as duration of diabetes, diet, exercise, or social support, could not be assessed.

Conclusions: Results indicate there are sharp and significant increases in medical costs among T2D patients with Stage 4 and 5 CKD compared to those with earlier stages of CKD.  相似文献   
80.
为了深入研究影响波节管传热效果的主要因素,应用CFD软件Fluent对波节管内流体的流动和传热特性进行数值模拟,分别研究了不同入口流速v(0.3,0.5,0.7和0.9 m/s)、波峰直径D_1(28,30,32,34和36 mm)、弧形段长S_1(34,23,17,13和10 mm)下波节管内流体的流动与传热特性。结果表明,不同型号波节管的努塞尔数(Nu)、流体压力损失以及综合性能随着入口流速的增加而增加;随着波峰直径D_1(弧形段长S_1)的增大,波节管的Nu先增大后减小,最后趋于一个相对稳定的值。当波节管的波峰直径D_1=34 mm时,波节管的传热性能最好,流体压力损失最大,综合性能最好;弧形段长S_1=23 mm时,波节管的换热性能最佳,流体压力损失最大,综合性能最好。通过参数正交分析可知,影响波节管传热效果的因素由强到弱依次为入口流速v、波峰直径D_1、弧形段长S_1。研究成果可为工程实际中提高波节管传热性能提供理论指导。  相似文献   
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