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Two Performance Indicators Assisted Infill Strategy for Expensive Many⁃Objective Optimization
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作者 Yi Zhao Jianchao Zeng Ying Tan 《Journal of Harbin Institute of Technology(New Series)》 2025年第5期24-40,共17页
In recent years,surrogate models derived from genuine data samples have proven to be efficient in addressing optimization challenges that are costly or time⁃intensive.However,the individuals in the population become i... In recent years,surrogate models derived from genuine data samples have proven to be efficient in addressing optimization challenges that are costly or time⁃intensive.However,the individuals in the population become indistinguishable as the curse of dimensionality increases in the objective space and the accumulation of surrogate approximated errors.Therefore,in this paper,each objective function is modeled using a radial basis function approach,and the optimal solution set of the surrogate model is located by the multi⁃objective evolutionary algorithm of strengthened dominance relation.The original objective function values of the true evaluations are converted to two indicator values,and then the surrogate models are set up for the two performance indicators.Finally,an adaptive infill sampling strategy that relies on approximate performance indicators is proposed to assist in selecting individuals for real evaluations from the potential optimal solution set.The algorithm is contrasted against several advanced surrogate⁃assisted evolutionary algorithms on two suites of test cases,and the experimental findings prove that the approach is competitive in solving expensive many⁃objective optimization problems. 展开更多
关键词 expensive multi⁃objective optimization problems infill sample strategy evolutionary optimization algorithm
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Surrogate-assisted differential evolution using manifold learning-based sampling for highdimensional expensive constrained optimization problems
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作者 Teng LONG Nianhui YE +2 位作者 Rong CHEN Renhe SHI Baoshou ZHANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第7期252-270,共19页
To address the challenges of high-dimensional constrained optimization problems with expensive simulation models,a Surrogate-Assisted Differential Evolution using Manifold Learning-based Sampling(SADE-MLS)is proposed.... To address the challenges of high-dimensional constrained optimization problems with expensive simulation models,a Surrogate-Assisted Differential Evolution using Manifold Learning-based Sampling(SADE-MLS)is proposed.In SADE-MLS,differential evolution operators are executed to generate numerous high-dimensional candidate points.To alleviate the curse of dimensionality,a Manifold Learning-based Sampling(MLS)mechanism is developed to explore the high-dimensional design space effectively.In MLS,the intrinsic dimensionality of the candidate points is determined by a maximum likelihood estimator.Then,the candidate points are mapped into a low-dimensional space using the dimensionality reduction technique,which can avoid significant information loss during dimensionality reduction.Thus,Kriging surrogates are constructed in the low-dimensional space to predict the responses of the mapped candidate points.The candidate points with high constrained expected improvement values are selected for global exploration.Moreover,the local search process assisted by radial basis function and differential evolution is performed to exploit the design space efficiently.Several numerical benchmarks are tested to compare SADE-MLS with other algorithms.Finally,SADE-MLS is successfully applied to a solid rocket motor multidisciplinary optimization problem and a re-entry vehicle aerodynamic optimization problem,with the total impulse and lift to drag ratio being increased by 32.7%and 35.5%,respec-tively.The optimization results demonstrate the practicality and effectiveness of the proposed method in real engineering practices. 展开更多
关键词 Surrogate-assisted differential evolution Dimensionality reduction Solid rocket motor Re-entry vehicle expensive constrained optimization
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A Bi-population Cooperative Optimization Algorithm Assisted by an Autoencoder for Medium-scale Expensive Problems 被引量:2
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作者 Meiji Cui Li Li +3 位作者 MengChu Zhou Jiankai Li Abdullah Abusorrah Khaled Sedraoui 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第11期1952-1966,共15页
This study presents an autoencoder-embedded optimization(AEO)algorithm which involves a bi-population cooperative strategy for medium-scale expensive problems(MEPs).A huge search space can be compressed to an informat... This study presents an autoencoder-embedded optimization(AEO)algorithm which involves a bi-population cooperative strategy for medium-scale expensive problems(MEPs).A huge search space can be compressed to an informative lowdimensional space by using an autoencoder as a dimension reduction tool.The search operation conducted in this low space facilitates the population with fast convergence towards the optima.To strike the balance between exploration and exploitation during optimization,two phases of a tailored teaching-learning-based optimization(TTLBO)are adopted to coevolve solutions in a distributed fashion,wherein one is assisted by an autoencoder and the other undergoes a regular evolutionary process.Also,a dynamic size adjustment scheme according to problem dimension and evolutionary progress is proposed to promote information exchange between these two phases and accelerate evolutionary convergence speed.The proposed algorithm is validated by testing benchmark functions with dimensions varying from 50 to 200.As indicated in our experiments,TTLBO is suitable for dealing with medium-scale problems and thus incorporated into the AEO framework as a base optimizer.Compared with the state-of-the-art algorithms for MEPs,AEO shows extraordinarily high efficiency for these challenging problems,t hus opening new directions for various evolutionary algorithms under AEO to tackle MEPs and greatly advancing the field of medium-scale computationally expensive optimization. 展开更多
关键词 Autoencoder dimension reduction evolutionary algorithm medium-scale expensive problems teaching-learning-based optimization
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Hybrid Meta-Model Based Design Space Differentiation Method for Expensive Problems 被引量:1
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作者 Nianfei Gan Guangyao Li Jichao Gu 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2016年第2期120-132,共13页
In this work,a hybrid meta-model based design space differentiation(HMDSD)method is proposed for practical problems.In the proposed method,an iteratively reduced promising region is constructed using the expensive p... In this work,a hybrid meta-model based design space differentiation(HMDSD)method is proposed for practical problems.In the proposed method,an iteratively reduced promising region is constructed using the expensive points,with two different search strategies respectively applied inside and outside the promising region.Besides,the hybrid meta-model strategy applied in the search process makes it possible to solve the complex practical problems.Tested upon a serial of benchmark math functions,the HMDSD method shows great efficiency and search accuracy.On top of that,a practical lightweight design demonstrates its superior performance. 展开更多
关键词 hybrid meta-model design space differentiation expensive problems global optimization
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Evolutionary Algorithm with Ensemble Classifier Surrogate Model for Expensive Multiobjective Optimization
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作者 LAN Tian 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第S01期76-87,共12页
For many real-world multiobjective optimization problems,the evaluations of the objective functions are computationally expensive.Such problems are usually called expensive multiobjective optimization problems(EMOPs).... For many real-world multiobjective optimization problems,the evaluations of the objective functions are computationally expensive.Such problems are usually called expensive multiobjective optimization problems(EMOPs).One type of feasible approaches for EMOPs is to introduce the computationally efficient surrogates for reducing the number of function evaluations.Inspired from ensemble learning,this paper proposes a multiobjective evolutionary algorithm with an ensemble classifier(MOEA-EC)for EMOPs.More specifically,multiple decision tree models are used as an ensemble classifier for the pre-selection,which is be more helpful for further reducing the function evaluations of the solutions than using single inaccurate model.The extensive experimental studies have been conducted to verify the efficiency of MOEA-EC by comparing it with several advanced multiobjective expensive optimization algorithms.The experimental results show that MOEA-EC outperforms the compared algorithms. 展开更多
关键词 multiobjective evolutionary algorithm expensive multiobjective optimization ensemble classifier surrogate model
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costly、dear和expensive的异同
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作者 丁玉玲 《语言教育》 1995年第8期24-24,共1页
costly、dear 和 expensive 是一组英文中颇为常见的形容词,汉语都译成“昂贵的”。然而,它们在意义上、用法上又各有不同,稍不留意就会出现误会,现分述如下:1.costly:昂贵的、价值高的(含有豪华、珍贵、精致等意味)。指“
关键词 costly expensive DEAR 法上 MISTAKE 器官移植 销售价 支付能力 afford
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Low-cost clothing outlasts expensive pieces
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作者 Susan 《新世纪智能》 2019年第15期28-30,共3页
If you’ve been shelling out for designer clothing in the hopes that it will be more durable than cheaper options, you might want to reconsider it. A new study from The University of Leeds suggests that low-cost cloth... If you’ve been shelling out for designer clothing in the hopes that it will be more durable than cheaper options, you might want to reconsider it. A new study from The University of Leeds suggests that low-cost clothing might actually outlast pricier pieces. 展开更多
关键词 LOW-COST CLOTHING outlasts expensive pieces
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不动声色 流露尊贵——Express expensiveness smoothly
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作者 Teacr 《汽车时代》 2003年第8期102-103,共2页
生活在被重视的空间里是很惬意的,对男人尤其如此。 生活在被忽略的氛围中是一件不可容忍的事,对男人尤其如此。 这样一来,问题就出现了。 第一是差额的问题:所有人都希望自己被看重,所有人都在规避被忽视的窘境。而任何时候,在喧闹的... 生活在被重视的空间里是很惬意的,对男人尤其如此。 生活在被忽略的氛围中是一件不可容忍的事,对男人尤其如此。 这样一来,问题就出现了。 第一是差额的问题:所有人都希望自己被看重,所有人都在规避被忽视的窘境。而任何时候,在喧闹的人群中,众人的目光从来不会过于分散,被瞩目的名额永远是有限的。不管那些对着焦点翘首张望的人们心里。 展开更多
关键词 Express expensiveness smoothly
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Evolutionary Computation for Expensive Optimization:A Survey 被引量:11
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作者 Jian-Yu Li Zhi-Hui Zhan Jun Zhang 《Machine Intelligence Research》 EI CSCD 2022年第1期3-23,共21页
Expensive optimization problem(EOP) widely exists in various significant real-world applications. However, EOP requires expensive or even unaffordable costs for evaluating candidate solutions, which is expensive for t... Expensive optimization problem(EOP) widely exists in various significant real-world applications. However, EOP requires expensive or even unaffordable costs for evaluating candidate solutions, which is expensive for the algorithm to find a satisfactory solution. Moreover, due to the fast-growing application demands in the economy and society, such as the emergence of the smart cities, the internet of things, and the big data era, solving EOP more efficiently has become increasingly essential in various fields, which poses great challenges on the problem-solving ability of optimization approach for EOP. Among various optimization approaches, evolutionary computation(EC) is a promising global optimization tool widely used for solving EOP efficiently in the past decades. Given the fruitful advancements of EC for EOP, it is essential to review these advancements in order to synthesize and give previous research experiences and references to aid the development of relevant research fields and real-world applications. Motivated by this, this paper aims to provide a comprehensive survey to show why and how EC can solve EOP efficiently. For this aim, this paper firstly analyzes the total optimization cost of EC in solving EOP. Then, based on the analysis, three promising research directions are pointed out for solving EOP, which are problem approximation and substitution, algorithm design and enhancement, and parallel and distributed computation. Note that, to the best of our knowledge, this paper is the first that outlines the possible directions for efficiently solving EOP by analyzing the total expensive cost. Based on this, existing works are reviewed comprehensively via a taxonomy with four parts, including the above three research directions and the real-world application part. Moreover, some future research directions are also discussed in this paper. It is believed that such a survey can attract attention, encourage discussions, and stimulate new EC research ideas for solving EOP and related real-world applications more efficiently. 展开更多
关键词 expensive optimization problem evolutionary computation evolutionary algorithm swarm intelligence particle swarm optimization differential evolution
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Classification- and Regression-Assisted Differential Evolution for Computationally Expensive Problems 被引量:6
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作者 陆晓芬 唐珂 《Journal of Computer Science & Technology》 SCIE EI CSCD 2012年第5期1024-1034,共11页
Differential Evolution (DE) has been well accepted ever, it usually involves a large number of fitness evaluations to as an effective evolutionary optimization technique. Howobtain a satisfactory solution. This disa... Differential Evolution (DE) has been well accepted ever, it usually involves a large number of fitness evaluations to as an effective evolutionary optimization technique. Howobtain a satisfactory solution. This disadvantage severely restricts its application to computationally expensive problems, for which a single fitness evaluation can be highly timeconsuming. In the past decade, a lot of investigations have been conducted to incorporate a surrogate model into an evolutionary algorithm (EA) to alleviate its computational burden in this scenario. However, only limited work was devoted to DE. More importantly, although various types of surrogate models, such as regression, ranking, and classification models, have been investigated separately, none of them consistently outperforms others. In this paper, we propose to construct a surrogate model by combining both regression and classification techniques. It is shown that due to the specific selection strategy of DE, a synergy can be established between these two types of models, and leads to a surrogate model that is more appropriate for DE. A novel surrogate model-assisted DE, named Classification- and Regression-Assisted DE (CRADE) is proposed on this basis. Experimental studies are carried out on a set of 16 benchmark functions, and CRADE has shown significant superiority over DE-assisted with only regression or classification models. Further comparison to three state-of-the-art DE variants, i.e., DE with global and local neighborhoods (DECL), JADE, and composite DE (CODE), also demonstrates the superiority of CRADE. 展开更多
关键词 surrogate model differential evolution computationally expensive problem
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Interpretation of Annual Report on Cardiovascular Health and Diseases in China 2024
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作者 Mingbo Liu Xinye He +1 位作者 Xiaohong Yang Zengwu Wang 《Biomedical and Environmental Sciences》 2025年第8期893-917,共25页
Cardiovascular diseases(CVD)and their risk factors are exerting an increasingly significant impact on public health,and the incidence rate of CVD continues to rise.This article provides an interpretation of essentials... Cardiovascular diseases(CVD)and their risk factors are exerting an increasingly significant impact on public health,and the incidence rate of CVD continues to rise.This article provides an interpretation of essentials from the newly published Annual Report on Cardiovascular Health and Diseases in China(2024),aiming to offer scientific evidence for CVD prevention,treatment,and the formulation of relevant policies. 展开更多
关键词 Cardiovascular diseases Epidemiology Burden of disease Risk factors PREVALENCE MORTALITY Rehabilitation Basic research Medical device development EXPENSE
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Historical Safe Haven in Shanghai
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作者 LU JIAJUN 《China Today》 2025年第9期36-41,共6页
IN the Shanghai Jewish Refugees Museum,a beautiful handbag is waiting for its owner in a display cabinet.The handbag belongs to a Jewish couple.When they sought refuge in Shanghai during World War II,they pawned the h... IN the Shanghai Jewish Refugees Museum,a beautiful handbag is waiting for its owner in a display cabinet.The handbag belongs to a Jewish couple.When they sought refuge in Shanghai during World War II,they pawned the handbag to Jin Wenzhen’s grandfather in exchange for their child’s medical expenses.He lent the couple the cash equivalent of one month’s revenue from his rice shop,but then never saw them again. 展开更多
关键词 rice shop Jewish refugees SHANGHAI historical safe haven pawned handbag medical expenses World War II
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Not Excessive,But Expensive
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作者 LAN XINZHEN 《Beijing Review》 2006年第16期58-60,共3页
China's real estate market presents a dilemma. Demand for housing continues to climb, but so does the number of vacant houses as developers hold fast to prices that few urban residents can afford
关键词 Not Excessive But expensive
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Large-Scale Expensive Optimization with a Switching Strategy
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作者 Mai Sun Chaoli Sun +2 位作者 Xiaobo Li Guochen Zhang Farooq Akhtar 《Complex System Modeling and Simulation》 2022年第3期253-263,共11页
Some optimization problems in scientific research,such as the robustness optimization for the Internet of Things and the neural architecture search,are large-scale in decision space and expensive for objective evaluat... Some optimization problems in scientific research,such as the robustness optimization for the Internet of Things and the neural architecture search,are large-scale in decision space and expensive for objective evaluation.In order to get a good solution in a limited budget for the large-scale expensive optimization,a random grouping strategy is adopted to divide the problem into some low-dimensional sub-problems.A surrogate model is then trained for each sub-problem using different strategies to select training data adaptively.After that,a dynamic infill criterion is proposed corresponding to the models currently used in the surrogate-assisted sub-problem optimization.Furthermore,an escape mechanism is proposed to keep the diversity of the population.The performance of the method is evaluated on CEC’2013 benchmark functions.Experimental results show that the algorithm has better performance in solving expensive large-scale optimization problems. 展开更多
关键词 large-scale optimization problems computationally expensive problems random grouping surrogate models
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Top Ten Most Expensive 亿万富翁的玩具
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作者 sky 《汽车与运动》 2007年第4期162-165,共4页
其实,这个题目还有一个定义才算完整,那就是以美元为计量单位。怎么样,看到这里,你是否会觉得这些汽车有点贵得离谱了呢?
关键词 法拉利 保时捷 Top Ten Most expensive 梅赛德斯 GTR 雷希特
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LIVIN’IT UP It's Expensive to Be Rich in Shanghai
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作者 Matthew Minford 《城市漫步(上海版、英文)》 2019年第1期7-7,共1页
Singapore might be where the film Crazy Rich Asians is set,but in terms of the most expensive city for luxury living,Shanghai is at the top of the list among all metropolises in the continent.
关键词 RICH SINGAPORE expensive
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Hong Kong Ousts Tokyo as Most Expensive City
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作者 郎岳秀 《当代外语研究》 2002年第8期12-13,共2页
根据一家人力资源顾问公司(Mercer Human Resource Consulting)公布的全球生活指数调查的结果,香港的生活指数已经取代日本东京而成为全球生活指数最高的城市。第2位是莫斯科,东京则下跌为第3位。根据调查,香港生活指数上升,主要是个人... 根据一家人力资源顾问公司(Mercer Human Resource Consulting)公布的全球生活指数调查的结果,香港的生活指数已经取代日本东京而成为全球生活指数最高的城市。第2位是莫斯科,东京则下跌为第3位。根据调查,香港生活指数上升,主要是个人护理、家居用品和交通项目费用高昂所致。调查同时研究了144个城市,比较其住房、食品、衣服、交通和娱乐等超过200项消费项目。在全球15个生活指数最高的城市当中,有11个位于亚洲,北京与上海分别排行第4位和第5位。调查发现,新西兰和澳大利亚的城市依然是生活费用便宜但生活质量最高的地方,大多数澳大利亚和新西兰城市的生活指数都在全球生活费用最高昂城市的一半以下。至于生活指数最低的城市则是南非的约翰内斯堡。布宜诺斯艾利斯(阿根廷首都)的生活指数则因国内经济不景气,而有一个dramatic fall。本文文字表达不乏可记学之处,如Moscow muscles in at secondplace in the survey一句中的muscles in就值得咀嚼一番。它是美国俚语,意思是:发挥臂力;靠力气前进,硬性挤入。另如:muscle through a crowd/用力挤过人群;muscle in on a 展开更多
关键词 阿根廷 约翰内斯堡 布宜诺斯艾利斯 生活指数 Hong Kong Ousts Tokyo as Most expensive City
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Carbamazepine in osteoarthritis treatment:A novel approach targeting Nav1.7 channels 被引量:1
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作者 Rayyan Vaid Afra Sohail Nabiha Amir 《World Journal of Orthopedics》 2024年第6期602-604,共3页
Osteoarthritis(OA)presents a growing health concern,with substantial societal and healthcare burdens.Current management focuses on symptom relief,lacking disease-modifying options.Emerging research suggests the sodium... Osteoarthritis(OA)presents a growing health concern,with substantial societal and healthcare burdens.Current management focuses on symptom relief,lacking disease-modifying options.Emerging research suggests the sodium channel Nav1.7 as a pivotal target in OA treatment.Preclinical studies demonstrate carbamazepine's efficacy in Nav1.7 blockade,offering significant joint protection in animal models.However,human trials are needed to validate these findings.Carbamazepine's repurposing holds promise for OA management,potentially revolutionizing treatment paradigms.Further research is essential to bridge the gap between preclinical evidence and clinical application,offering hope for improved OA management and enhanced patient quality of life. 展开更多
关键词 OSTEOARTHRITIS Joint illness Treatment approaches Pain management Healthcare expenses
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Effects of formal credit on pastoral household expense: Evidence from the Qinghai-Xizang Plateau of China
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作者 Yan Zhang Yi Huang +1 位作者 Fan Zhang Zeng Tang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1774-1785,共12页
Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.Howeve... Formal credit is critical in agricultural production,allowing more expenditure and productive input,thereby improving farmers'welfare.In pastoral China,formal financial institutions are gradually increasing.However,a limited understanding remains of how formal credit affects herders'household expenses.Based on a survey of 544 herders from the Qinghai-Xizang Plateau of China,this study adopted the propensity score matching approach to identify the effect of formal credit on herders'total household expenses,daily expenses,and productive expenses.The results found that average age,grassland mortgage,and other variables significantly affected herders'participation in formal credit.Formal credit could significantly improve household expenses,especially productive expenses.A heterogeneity analysis showed that formal credit had a greater impact on the household total expense for those at higher levels of wealth;however,it significantly affected the productive expense of herders at lower wealth levels.Moreover,the mediating effect indicated that formal credit could affect herders'household income,thus influencing their household expenses.Finally,this study suggests that policies should improve herders'accessibility to formal credit. 展开更多
关键词 formal credit herders EXPENSE Qinghai-Xizang Plateau
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Cumulative Effect of Debt and Tax on Firm Value:Optimal Capital Structure Theories in the Light of EMM
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作者 Valery V.Shemetov 《Management Studies》 2024年第5期255-276,共22页
We have shown that cornerstone articles considering effects of corporate debt on the firm value and constituting the basis of the trade-off theory of capital structure are wrong.Their main mistake is in ignoring the b... We have shown that cornerstone articles considering effects of corporate debt on the firm value and constituting the basis of the trade-off theory of capital structure are wrong.Their main mistake is in ignoring the business securing expenses(BSEs).In the framework of the extended Merton model(EMM),we consider the cumulative effect of debt and corporate taxes on the firm value and its survival,in other words,we revisit Modigliani-Miller Proposition 3(MMP3).We show that(1)debt affects the firm value and its survival,(2)this effect is negative,diminishing the firm value and its chances to survive,(3)the pressure increases as the debt grows provoking the firm’s default,(4)the main factors depressing the levered firm are its debt payments added to the BSEs of the identical unlevered firm and the length of debt maturity,(5)corporate taxes cause development of positive skewness in the asset distribution,but do not affect the location of this distribution in the asset axis.The presented model helps estimate the consequences of choosing this or that level of debt in the presence of corporate taxes and can make a useful instrument for practicing financial managers. 展开更多
关键词 geometric Brownian motion(GBM) extended Merton model business securing expenses corporate debt corporate taxes default probability
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