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51.
We investigate the economic feasibility of bioelectricity production from biomass in Malaysia and its impact on greenhouse gas (GHG) emissions and storage, agricultural prices, agricultural employment and deforestation. For this purpose, we develop a partial equilibrium model that projects agricultural prices, production, imports, exports, domestic consumption and land use in 5‐year increments between 2015 and 2065. Our results show that by 2030 biomass‐generated electricity can supply 36.5 per cent of the electricity generated in Malaysia, 16 times more than the 2016 electricity supply from biomass. Increased bioelectricity production from biomass will significantly reduce GHG emissions and will help Malaysia meet its commitment in the Paris Agreement to mitigate GHG emission by 45 per cent before 2030. Our modelling shows that biomass‐generated electricity creates a derived demand for waste biomass that expands the area of oil palm plantations. The expansion lowers agricultural prices, boosts agricultural employment and leads to some deforestation as landowners clear rainforest to plant oil palm trees. Nonetheless, the deforestation does not increase GHG emissions since GHG gains from bioelectricity significantly exceed GHG losses from deforestation.  相似文献   
52.
人工智能的发展是生产力进步的表现,但广泛使用人工智能技术的经济效应尚待深入研究。基于人工智能对劳动的替代作用,将人工智能投资引入动态随机一般均衡模型,通过比较静态分析和短期动态分析考察人工智能发展对通胀动态的影响。稳态分析表明:人工智能投资效率提高和使用范围扩大均会提升劳动生产率进而提高产出水平,但对长期或趋势通胀没有影响;在人工智能发展初级阶段人工智能的发展会引起实际工资下降,而在相对高级阶段人工智能的发展会引起实际工资上升。短期动态分析显示:人工智能发展水平的提高,无论是投资效率的提高还是使用范围的扩大,都会导致通胀及实际边际成本对偏好冲击和技术冲击等外生冲击的反应变弱。人工智能的发展会使通胀动态与实际经济活动变化间的联系减弱,其原因是人工智能对劳动的替代作用使工资调整不再是应对外生冲击的必然选择,进而改变了外生冲击通过影响工资来影响通胀的传导机制。因此,发展人工智能在促进生产率提升和产出增长的同时,还会改变宏观经济变量间的传导机制,进而对通胀等政策调控目标变量的准确预测以及政策调整和实施的有效性带来新的挑战,也为金融理论研究提出新的课题。  相似文献   
53.
由于企业的对外直接投资(OFDI)存在制度适应成本,东道国与母国之间的制度距离会对企业OFDI产生负向影响。基于2003—2015年中国对140个国家和地区OFDI的分析表明:中国企业的OFDI具有明显的市场寻求动机和战略资源寻求动机,其中,市场寻求型OFDI表现出显著的互补效应,战略资源寻求型OFDI表现出一定程度的挤出效应;东道国与中国的制度距离会通过投资动机影响中国企业OFDI的区位选择,即倾向于向制度距离较小的国家和地区进行OFDI,且制度距离会弱化市场寻求型OFDI的互补效应和战略资源寻求型OFDI的挤出效应。站在企业角度来看,中国企业在进行OFDI时并不具有“制度风险偏好”,而是表现出“制度风险规避”特征:选择对其自身发展来讲制度风险较小(制度距离较小)的目标市场进行OFDI。因此,中国应深化市场经济体制改革,提升国内制度质量,加强国际经济合作,并增强企业的制度适应能力,以有效减小制度距离对企业OFDI区位选择的约束,进而优化OFDI区位分布,提高OFDI效益和质量。  相似文献   
54.
We estimate the impact of shipping cost on development for landlocked developing countries (LLDCs). Since container trade is important to them, we construct a country-specific measure of shipping cost, called HarpexCost, which combines the global cost of container shipping with information on how exposed to container shipping each LLDC is. We employ the common correlated effects (CCE) estimator of Pesaran (Econometrica, 2006; 55: 967) to first estimate the impact of HarpexCost on the LLDCs’ development, and then recover the actual impact of shipping cost from these estimates. Overall, we observe that shipping cost has large negative effects on the LLDCs. Building upon these results, we provide new estimates on the cost of landlockedness and how trade benefits their development.  相似文献   
55.
Aims: To model direct medical costs associated with reductions in cardiovascular disease (CVD) events in T2DM patients reported in the CANVAS and EMPA-REG trials, which assessed the cardiovascular safety of canagliflozin and empagliflozin, respectively.

Materials and methods: Costs were modeled from a US managed care organization (MCO) perspective for the CVD outcomes included in both trials: three-point major adverse cardiovascular event (MACE) and its components (cardiovascular-related death, nonfatal myocardial infarction, nonfatal stroke), as well as heart failure requiring hospitalization. The rate of CVD events averted (difference between study drug and placebo) was projected to the portion of an MCO T2DM population matching the respective trial’s inclusion criteria. A targeted literature search for paid amounts directly associated with each CVD event provided the unit costs, which were applied to the projected number of events averted, to calculate costs avoided per member per year (PMPY). One-way sensitivity analyses were performed on events averted, unit costs, and percentages of trial-applicable patients.

Results: Based on three-point MACE events averted, costs avoided PMPY of $6.17 (range: $1.27–$10.94) for CANVAS and $2.75 ($0.19–$4.83) for EMPA-REG were estimated. Costs avoided for individual components of MACE ranged from $0.77 to $3.84 PMPY for CANVAS and from -$0.97 (additional costs) to $1.54 for EMPA-REG. PMPY costs avoided for heart failure were $2.72 for CANVAS and $1.32 for EMPA-REG.

Limitations and conclusions: Models assumed independent, non-recurrent outcomes and were restricted to medical costs directly associated with the trial-reported events. The reductions in CVD events in T2DM patients reported for both CANVAS and EMPA-REG project to a positive cost avoidance for these events in an MCO population. The analysis did not include an assessment of the impact on total cost, as the costs associated with adverse events, drug utilization or other clinical outcomes were not examined.  相似文献   

56.
以林农拥有的活立木为研究对象,利用2007—2017年浙江省1546宗活立木流转样本,采用多元线性回归实证分析了是否在林权交易中心交易对活立木流转价格存在影响。结果表明:关键解释变量是否在林权交易中心进行交易对活立木流转价格具有显著的正向影响;流转面积、单位面积蓄积、区域虚拟变量、坡度等对流转价格都产生一定程度的影响;流转期限对流转价格的影响不大。因此,需要加强对林权交易中心的宣传,降低相关的交易成本,从而吸引更多的小规模林农参与交易。  相似文献   
57.
This paper studies investment dynamics in Chinese manufacturing firms. The analysis estimates capital adjustment costs and uncovers capital distortion in state and non-state firms. There is strong evidence of quadratic adjustment cost and distortion in capital price for both types of firms. The capital distortion is a major source of capital misallocation in Chinese firms. Completely removing the distortion would increase aggregate total factor productivity (TFP) by 18–29%.  相似文献   
58.
Aims: This study aimed to evaluate the budget impact of niraparib and olaparib in patients with platinum-sensitive, recurrent ovarian cancer from a US third party payer perspective.

Materials and methods: A budget impact model was constructed to assess the additional per member per month (PMPM) costs associated with the introduction of niraparib and olaparib, two poly ADP-ribose polymerase ribose polymerase (PARP) inhibitors recently approved to be used in platinum-sensitive, recurrent ovarian cancer patients with and without a gBRCA mutation. The model assessed both pharmacy costs and medical costs. Pharmacy costs included adjusted drug costs, coinsurance, and dispensing fees. Medical costs included costs associated with disease monitoring and management of adverse events from the treatment. Epidemiological data from the literature were used to estimate the target population size. The analysis used 1-year time frame, and patients were assumed on treatment until disease progression or death. All costs were computed in 2017 USD. One-way sensitivity analyses were conducted to evaluate the model robustness.

Results: In a hypothetical plan of 1,000,000 members, 206 patients were estimated to be potential candidates for niraparib or olaparib maintenance treatment after applying all epidemiological parameters. At listed 30-day supply WAC prices of $14,750 for niraparib and $13,482 for olaparib, budget impacts of these two drugs were $0.169 PMPM and $0.156 PMPM, respectively, most of which were contributed by pharmacy costs. Sensitivity analyses suggested that assumptions around market share, platinum-sensitive rate after first treatment, and WAC prices affected results the most.

Limitations: In this model, it was assumed that adopting niraparib and olaparib would not affect utilization of existing medications. Also, the estimated clinical parameters from clinical trials could differ from real-world data.  相似文献   

59.
研究目的:探讨耕作层土壤剥离再利用空间配置思路与方法,并以南昌市为例进行实证研究,为相关工作提供借鉴。研究方法:提出基于线性规划及OD成本矩阵方法的两次平衡计算的耕作层土壤剥离再利用土方空间配置思路。首先,确定剥离、覆土优先度并结合供求关系划定供需圈,在供需圈内部进行第一次调配平衡;其次,对于内部不能平衡的供需圈,进行第二次跨圈调配平衡,达到缩短运输距离,控制成本目的。研究结果:(1)南昌市耕作层剥离量能够满足覆土数量与质量的需求;(2)空间配置结果共划定18个供需圈,供需圈内土方调配加权平均运输距离为6 682 m,小于期望值10 km,满足项目实施要求;(3)共有15个供需圈存在土方量不平衡问题,跨圈调配的距离平均为72 071 m,满足短距离运输的要求。研究结论:以耕作层土壤剥离、覆土优先度及供求关系为基础划定供需圈,基于线性规划及OD成本矩阵的两次平衡计算的空间配置思路与方法,可以优化运输距离,减少运输成本,提高项目实施效益。本文提出的空间配置思路可以为耕作层剥离再利用工程的顺利实施提供理论与方法借鉴。  相似文献   
60.
This study highlights how social and commercial enterprises with local and global presence, balance their economic and social goals, to sustainably serve the bottom-of-the-pyramid (BoP) markets, predominantly in emerging economies. Employing the lens of transaction cost economics and configurational theory, we propose that successful venturing into the BoP markets, sensitize firms to create appropriate governance mechanisms for reducing transaction costs, resulting in creation and capture of values. Further, these mechanisms enable those firms to attain cost efficiency and sustainability in the process of fulfilling their social objectives. To that end, we employed the case survey method to analyse 42 cases, from the Harvard Business School repository, on multinational enterprises (MNEs) in emerging economies. Further, we used qualitative comparative analysis to uncover the various causal governance configurations that enabled those firms to sustainably serve the BoP markets.  相似文献   
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