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21.
[目的]构建科学合理的评价指标体系,准确评价生态旅游影响下的区域生态安全状况,是推动少数民族山区实现旅游资源环境与区域社会、经济协同发展的前提和基础。[方法]以岷江上游贫困山区为例,应用灰色系统理论与熵值赋权法相结合,基于压力—状态—响应模型,构建生态旅游视域下的区域生态安全评估指标体系,并将评估指数与经济收入状况及贫困人口分布进行空间耦合。[结果](1)区域当前处于较安全水平,生态旅游开发适度;(2)综合评估指数与城镇居民可支配收入增长率、旅游收入对国民经济增长的贡献率呈正相关,且城镇居民在旅游开发中受益与机会较农牧民多;(3)综合评估指数与贫困人口比重呈负相关,与农牧民纯收入增长率没有必然联系。[结论]区域脱贫能够改善当地的生态安全状况,适度生态旅游开发是区域脱贫的有效手段,但应注重扶持农牧民在旅游业中的参与度,增加其旅游收益。  相似文献   
22.
Research Summary: We study the use of corporate philanthropy as a form of reputation insurance, developing a formal model of such insurance to examine how the terms of insurance in equilibrium change under different assumptions about the firm and its stakeholders. We then test the predictions from this model in the U.S. petroleum industry and find that philanthropic donations offer insurance‐like benefits, but are also positively associated with subsequent oil spills—firms that give more, spill more—with this association being stronger for spills that are under firms’ control and in states with low civic capacity. These results are consistent with an adverse selection/moral hazard equilibrium and suggest that the use of philanthropy as reputation insurance may benefit firms at the cost of society. Managerial Summary: Firms that donate to social causes develop a reputation for being socially responsible, and are often given the benefit of doubt when negative information about them comes to light. But are philanthropic firms truly more responsible? We argue that firms that donate more may be more likely to do harm—those that expect to do harm later are likely to give more now, and those that know their reputation protects them may become less careful. Evidence from the U.S. petroleum industry is consistent with this argument, with firms that give more having more subsequent oil spills, but only the type of spills that are under the firm's control, and only in states where the firm faces weaker scrutiny.  相似文献   
23.
This article studies poverty persistence and the role of social security programmes on poverty among elderly in the US. We use a Latent Markov model to disentangle unobserved heterogeneity and state dependence. Because of its dynamic nature, unobserved heterogeneity is modelled to vary over time. This allows to capture different latent states of poverty that change over time. Result indicates the existence of three unobserved types evolving over time according to their propensity to be poor. Moreover, a strong persistence in poverty especially for women, individuals living alone and ethnic minorities is found. Finally, the estimates indicate that giving social assistance tends to reduce poverty.  相似文献   
24.
[目的]通过对我国北方地区大规模生猪养殖技术效率进行测度,以期发现影响其技术效率增长的主要因素,为我国现阶段生猪养殖业战略性区划调整"南猪北进"工作提供实践指导和理论支持。[方法]根据随机前沿分析方法 (SFA)基本原理,运用对数型柯布—道格拉斯生产函数及我国北方大规模生猪养殖数据构建中国北方大规模生猪养殖随机前沿分析模型,对我国北方大规模生猪养殖技术效率进行测度并据此提出相关建议。[结果]北方地区大规模生猪养殖技术效率值纵向上来看整体在不断下降,而从地域上来看内蒙古自治区和东北地区技术效率值较高,北京与西北地区技术效率值较低。[结论]内蒙古自治区与东北地区适宜作为大规模生猪养殖承载地,与国家政策具有一致性;华北地区与西北地区大规模生猪养殖技术效率测度值较低,存在较大改进空间;针对该现状提出构建经济效益与环境保护并重的规模生态生猪养殖体系。  相似文献   
25.
江西省农村土地利用变化及生态系统服务价值研究   总被引:2,自引:0,他引:2  
[目的]土地利用变化及生态系统服务价值研究一直是土地资源评价与管理方面的热点研究问题,通过对江西省土地利用变化和生态系统价值进行研究,为江西省土地规划和资源的可持续利用提供理论依据。[方法]文章基于文献查阅的方法,利用多样性指数模型、土地利用动态度和生态系统服务价值模型,结合2009~2016年江西省农村土地利用的现状及变化,分析了其生态系统服务价值及相应变化。[结果]近年来,江西省农村土地利用程度高、多样性指数中等且呈先下降后上升的趋势。土地利用类型的面积与该土地利用类型的生态系统服务价值呈同向变化的关系。通过对土地利用类型的ESV值进行分析,发现农村土地利用的生态系统服务功能价值总体在减少;对单项生态系统价值分析,水源涵养在江西省农村土地生态系统服务中占有最重要的地位。[结论]2009~2016年江西省农村土地利用结构都发生了变化,生态系统服务总价值出现了降低趋势,各单项生态系统服务功能价值也在减少,土地利用结构对生态系统功能价值具有决定作用。因此,政府应该合理利用土地,保护生态系统,协调好环境与经济发展的关系。  相似文献   
26.
We present a theoretical methodology for the pricing of catastrophe (CAT) derivatives with event‐dependent and non‐convex payoffs given the price of a CAT indexed futures contract. We do not assume a fully diversifiable CAT event risk, nor do we assume knowledge of the martingale probability measure beyond the futures price. We derive tight bounds on the contract value and present trading strategies exploiting the mispricing whenever the bounds are violated. We estimate the bounds of the reinsurance contract with data from hurricane landings in Florida. Our method is also applicable when there is no futures market but the price of a CAT‐indexed bond is available.  相似文献   
27.
Academic research suggests a number of technology evaluation models. To ensure effective use, models need to be improved in accordance with changing internal and external environments. However, a majority of previous studies focus on model development, while a few emphasize their implementation or improvement. To fill this research gap, this study suggests a systematic approach to examining the validity of technology evaluation models and improving them. We consider three propositions as criteria for improvement: 1) the coherence of the evaluation results with the evaluation purpose, 2) the appropriateness of the evaluation methods, and 3) the concreteness of the evaluation model. Rather than using expert opinions, this study takes a data-driven approach, wherein we analyze actual evaluation results and determine whether the model produces the intended results. A case study of 291 technology evaluation results, all made by the South Korean government in support of technology-based small and medium-sized enterprises, is conducted to verify the suggested approach's applicability. This is one of the few studies to address issues regarding improvements to a technology evaluation model. Its approach can help to develop and continuously improve a valid technology evaluation model, thus leading to more effective practice.  相似文献   
28.
We propose a novel class of convex risk measures, based on the concept of the Fréchet mean, designed in order to handle uncertainty which arises from multiple information sources regarding the risk factors of interest. The proposed risk measures robustly characterize the exposure of the firm, by filtering out appropriately the partial information available in individual sources into an aggregate model for the risk factors of interest. Importantly, the proposed risks can be expressed in closed analytic forms allowing for interesting qualitative interpretations as well as comparative statics and thus facilitate their use in the everyday risk management process of the insurance firms. The potential use of the proposed risk measures in insurance is illustrated by two concrete applications, capital risk allocation and premia calculation under uncertainty.  相似文献   
29.
Trade openness is an important determinant of the inflation process. The effect of trade openness on inflation, however, is still an issue of debate at both theoretical and empirical levels. This study tried to provide a contribution to the literature by examining the relationship between inflation and trade openness in Tunisia over the period 1975Q1-2015Q4 using a nonlinear model. The originality of this study stems from the fact that it is the first investigation considering both the Residual-Based Tests for Cointegration in Models with the Regime Shifts and Threshold Regression model. The linear model confirms the existence of a positive relationship between inflation and trade in Tunisia. Yet, considering the nonlinear model, trade openness growth and Consumer Price Index (CPI) inflation growth show a statistically significant negative link as long as the trade openness evolution does not exceed the threshold. Nevertheless, if the trade openness growth is higher than the threshold, integrating the trade positively affects CPI inflation. Furthermore, a positive influence of Money supply growth on this type of inflation was noticed in Tunisia in all the considered regimes proving the effect of monetary factors on inflation level. Consequently, trade openness could be used to control inflation in Tunisia.  相似文献   
30.
当前企业推进绿色转型进程、提升企业绩效,是实现高质量发展的重要途径。鉴于企业主动应对内外部因素联动影响的重要性,以动态能力理论视角,在探讨了企业变革发展驱动机制的基础上,尝试构建动态环境规制嵌入下的战略柔性与企业绩效的理论框架。分析并实证检验了战略柔性对企业绩效以及差异化强度的动态环境规制在二者关系中调节效应的作用机理和边界。研究结果显示,当前情境下,前瞻柔性、响应柔性对企业绩效均有显著的正向影响,且响应柔性的贡献度较高;两者交互效应亦能显著的正向影响企业绩效;表明企业对环境变化的预测、反应能力以及将两者协同配合是绿色转型发展的重要措施。一般强度的动态环境规制在前瞻柔性、响应柔性与企业绩效的关系中均不起显著的调节效应;高强度动态环境规制仅在响应柔性和企业绩效的关系中起显著负向调节效应;表明动态环境下,一般强度的政府规制政策对企业的决策和创新等行为更多的是无显著影响,充分尊重其自主发展;同时政府要根据环境变化,合理控制环境规制实施强度,谨防给企业应对环境冲击造成额外的负担。综合研究结果,提出企业加强多重柔性机制建设的力度和政府注重环境规制政策引导作用的策略,最终实现各利益相关者协同推进高质量发展的目标。  相似文献   
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