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Application of modified two-point hedging policy in groundwater resources planning in the Kashan Plain Aquifer
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作者 Marzie Ghorbaniaghdam Hossein Khozeymehnezhad +1 位作者 Mohsen Pourreza bilondi Hoda Ghasemie 《Journal of Groundwater Science and Engineering》 2025年第1期62-73,共12页
Effective management of water resources,especially groundwater,is crucial and requires a precise understanding of aquifer characteristics,imposed stresses,and the groundwater balance.Simulation-optimization models pla... Effective management of water resources,especially groundwater,is crucial and requires a precise understanding of aquifer characteristics,imposed stresses,and the groundwater balance.Simulation-optimization models plays a vital role in guiding planners toword sustainable long-term aquifer exploita-tion.This study simulated monthly water table variations in the Kashan Plain over a ten-year period from 2008 to 2019 across 125 stress periods using the GMS model.The model was calibrated for both steady-state and transient conditions for the 2008–2016 period and validated for the 2016–2019 period.Results indicated a 4.4 m decline in groundwater levels over the 10-year study period.Given the plain's location in a arid climatic zone with limited effective precipitation for aquifer recharge,the study focused on ground-water extraction management.A modified two-point hedging policy was employed as a solution to mitigate critical groundwater depletion,reducing the annual drawdown rate from 0.44 m to 0.31 m and conserving 255 million cubic meters(mcm)of water annually.Although this approach slightly decreased reliability(i.e.the number of months meeting full water demands),it effectively minimized the risk of severe droughts and irreparable damages.This policy offers managers a dynamical and intelligent tool for regulating groundwater extraction,balancing aquifer sustainability with agricultural and urban water requirements. 展开更多
关键词 Calibration GMS Groundwater simulation-optimization model Modified two-point hedging policy Sustainable operation
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Dynamic hedging of 50ETF options using Proximal Policy Optimization
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作者 Lei Liu Mengmeng Hao Jinde Cao 《Journal of Automation and Intelligence》 2025年第3期198-206,共9页
This paper employs the PPO(Proximal Policy Optimization) algorithm to study the risk hedging problem of the Shanghai Stock Exchange(SSE) 50ETF options. First, the action and state spaces were designed based on the cha... This paper employs the PPO(Proximal Policy Optimization) algorithm to study the risk hedging problem of the Shanghai Stock Exchange(SSE) 50ETF options. First, the action and state spaces were designed based on the characteristics of the hedging task, and a reward function was developed according to the cost function of the options. Second, combining the concept of curriculum learning, the agent was guided to adopt a simulated-to-real learning approach for dynamic hedging tasks, reducing the learning difficulty and addressing the issue of insufficient option data. A dynamic hedging strategy for 50ETF options was constructed. Finally, numerical experiments demonstrate the superiority of the designed algorithm over traditional hedging strategies in terms of hedging effectiveness. 展开更多
关键词 B-S model Option hedging Reinforcement learning 50ETF Proximal Policy Optimization(PPO)
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Dynamic connectedness and hedging opportunities of the commodity and stock markets in China:evidence from the TVP-VAR and cDCC-FIAPARCH
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作者 Binlin Li Nils Haneklaus Mohammad Mafizur Rahman 《Financial Innovation》 2024年第1期1944-1973,共30页
This study examines the dynamic connectedness and hedging opportunities between CSI300(China Security Index 300)and copper,gold,PTA(purified terephthalic acid),and soybean in China from January 09,2008,to June 30,2023... This study examines the dynamic connectedness and hedging opportunities between CSI300(China Security Index 300)and copper,gold,PTA(purified terephthalic acid),and soybean in China from January 09,2008,to June 30,2023.A TVP-VAR and cDCC-FIAPARCH modeling framework was used for the empirical investigation.The results show that the total connectedness index can effectively capture cross-asset information transmission in China’s financial markets.Copper returns are the dominant volatility transmitters,while CSI300,gold,and soybean returns are net recipients.The Russian-Ukraine war reinforced the safe-haven role of gold.Finally,investors with CSI300 long positions may benefit from prioritizing gold for hedging,while those with CSI300 short positions profit more from allocating gold to PTA.Portfolio managers and investors can use the findings to track the dynamics of systemic risk and adjust their long/short positions when investing in China's stock and commodity markets. 展开更多
关键词 TVP-VAR connectedness SPILLOVER hedging effectiveness Breitung-Candelon spectral Granger causality tests
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An Exploratory Study of Hedging in Chinese ESL Learners' Academic
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作者 陈玮 《海外英语》 2013年第11X期41-43,49,共4页
Hedging, referring to the use of various lexical and syntactic features modifying and mitigating propositions and claims, is extensively employed in effective academic writing. However, the use of hedges seems to be q... Hedging, referring to the use of various lexical and syntactic features modifying and mitigating propositions and claims, is extensively employed in effective academic writing. However, the use of hedges seems to be quite problematic for lots of Chinese ESL learners. In view of the situation, this study explores the use of hedges in academic abstracts by a group of undergraduate English majors in a university in Hainan Province. After analyzing data from a corpus and interviews, several problems have been found in the use of hedging devices of these students, and relevant implications have been drawn to the teaching of hedging in the context, which can help the students produce more effective academic writing and to achieve greater university success. 展开更多
关键词 hedgING use of hedgES ACADEMIC abstracts problems
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Hedge Trimmer句子压缩技术的算法实现及改进 被引量:1
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作者 景秀丽 《沈阳师范大学学报(自然科学版)》 CAS 2012年第4期519-524,共6页
压缩技术旨在模拟人类的文本概括和信息提取能力。句子压缩技术是自动生成能够保留原句核心内容的,合乎语法的,语义连贯的简短句子。文章分析了英文句子压缩技术中基于句法分析的Hedge Trimmer压缩技术,讨论了相关压缩理论,探索其压缩... 压缩技术旨在模拟人类的文本概括和信息提取能力。句子压缩技术是自动生成能够保留原句核心内容的,合乎语法的,语义连贯的简短句子。文章分析了英文句子压缩技术中基于句法分析的Hedge Trimmer压缩技术,讨论了相关压缩理论,探索其压缩过程并用类C语言进行算法实现。提出了好的压缩句应该至少满足以下3个标准:第一是保留原句的核心内容,第二是具有正确的语法,第三是压缩长度合理。在算法的评估工作中,从DUC 2003语料库中选取了624个原始句子和对应的人工压缩句,与Hedge Trimmer压缩算法自动生成的压缩句进行对照分析。发现5种压缩效果不理想的情况,分析其原因并提出了改进策略。最后,通过实例对改进算法生成的压缩句和原来算法生成的压缩句进行对比评估,证明了改良算法能够获得更理想的压缩句。在英文句子压缩领域,改良的Hedge Trimmer句子压缩算法值得推广和应用。 展开更多
关键词 句子压缩 hedgE Trimmer算法 评估 改进
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Enabling weakened hedges in linguistic multi-criteria decision making
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作者 王海 徐泽水 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期125-131,共7页
A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based o... A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based on the semantics of terms on the domain. Then, the hedges can be represented after the upper and loose upper approximations of a linguistic term are derived. Accordingly, some compact formulae can be derived for the semantics of linguistic expressions with hedges. Parameters in these formulae are objectively determined according to the semantics of original terms. The proposed model presents a more natural way to express the decision information under uncertainties and its semantics is clear. The proposed model is clarified by solving the problem of evaluation and selection of sustainable innovative energy technologies. Computational results demonstrate that the model can deal with various uncertainties of the problem. Finally, the model is compared with existing techniques and extended to the case when the semantics of terms are represented by trapezoidal fuzzy numbers. 展开更多
关键词 decision making multi-criteria decision making linguistic term sets linguistic hedges similarity relation
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论言语中的Hedges
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作者 李茹 《黔南民族师范学院学报》 2005年第1期67-70,共4页
Hedge是一种极具特殊性的语言表达,许多语言学家研究发现它广泛地用于女性语体中。从语用角度来讲,它也是一种极其重要的表达手段,并充分体现言语交际中应遵守的合作原则和礼貌原则,同时在特定的语境下蓄含特殊的意义,它的主要用途。
关键词 hedgE 合作原则 礼貌原则
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Hedge fund replication using strategy specific factors
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作者 Sujit Subhash David Enke 《Financial Innovation》 2019年第1期179-197,共19页
Hedge funds have traditionally served wealthy individuals and institutional investors with the promise of delivering protection of capital and uncorrelated positive returns irrespective of market direction,allowing th... Hedge funds have traditionally served wealthy individuals and institutional investors with the promise of delivering protection of capital and uncorrelated positive returns irrespective of market direction,allowing them to better manage portfolio risk.However,the financial crisis of 2008 has heightened investor sensitivity to the high fees,illiquidity,lack of transparency,and lockup periods typically associated with hedge funds.Hedge fund replication products,or clones,seek to answer these challenges by providing daily liquidity,transparency,and immediate exposure to a desired hedge fund strategy.Nonetheless,although lowering cost and adding simplicity by using a common set of factors,traditional replication products might offer lower risk-reward performance compared to hedge funds.This research explores hedge fund replication further by examining the importance of constructing clones with specific factors relevant to each hedge fund strategy,and then compares the strategy specific clone risk and reward performance against both actual hedge fund performance and hedge fund clones constructed using a more general set of common factors.Testing shows that using strategy specific factors to replicate common hedge fund strategies can offer superior risk-reward performance compared to previous general model clones. 展开更多
关键词 hedge funds hedge fund replication Regression Trading strategies Strategy specific factors
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A Longitudinal Study of Hedges in Different Moves of EMRAs
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作者 寇英 《海外英语》 2013年第4X期228-231,共4页
This paper investigates the evolutionary change in the OF(OF) of hedges in different moves of EMRAs(EMRAs).Two corpora are established for longitudinal study,with Corpus A consisting of EMRAs from 1990-1994 and Corpus... This paper investigates the evolutionary change in the OF(OF) of hedges in different moves of EMRAs(EMRAs).Two corpora are established for longitudinal study,with Corpus A consisting of EMRAs from 1990-1994 and Corpus B from 2005-2009.Generally,no significant change has been found in overall use of hedges.However,apart from move 6,7 and 10,we have found some interesting changes in the other moves.On the one hand,the OF of hedges in move 1,move 3,move 4 and move 5 shows a significant increase.On the other hand,the OF of hedges in move 2,8,9 and move 11 show a significant decrease. 展开更多
关键词 longitudinal STUDY hedgES MOVES EMRAs
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基于PML及Hedge的物联网异构信息集成处理模型 被引量:6
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作者 王桐 赵春晖 焉晓贞 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第2期301-304,共4页
针对物联网前端感知信息的海量性和异构性问题,提出物联网异构信息集成处理体系结构,包括引入物联网异构数据交换标准并提出物联网异构信息处理方法.物联网异构信息集成方案在感知层、传输层及应用层进行.在感知层,模型对不同传感器或R... 针对物联网前端感知信息的海量性和异构性问题,提出物联网异构信息集成处理体系结构,包括引入物联网异构数据交换标准并提出物联网异构信息处理方法.物联网异构信息集成方案在感知层、传输层及应用层进行.在感知层,模型对不同传感器或RFID的信息进行归一化及数据清洗;在传输层和应用层,模型对这些异构物联网信息进行信息融合及智能处理.提出了新的基于Hedge文法的高效过滤算法以提高匹配引擎处理海量数据的能力. 展开更多
关键词 物联网 集成 PML 森林文法
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Tracking market and non-traditional sources of risks in procyclical and countercyclical hedge fund strategies under extreme scenarios:a nonlinear VAR approach 被引量:1
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作者 François-Éric Racicot Raymond Théoret 《Financial Innovation》 2022年第1期696-751,共56页
The subprime crisis was quite damaging for hedge funds.Using the local projection method(Jordà2004,2005,2009),we forecast the dynamic responses of the betas of hedge fund strategies to macroeconomic and financial... The subprime crisis was quite damaging for hedge funds.Using the local projection method(Jordà2004,2005,2009),we forecast the dynamic responses of the betas of hedge fund strategies to macroeconomic and financial shocks—especially volatility and illiquidity shocks—over the subprime crisis in order to investigate their market timing activities.In a robustness check,using TVAR(Balke 2000),we simulate the reaction of hedge fund strategies’betas in extreme scenarios allowing moderate and strong adverse shocks.Our results show that the behavior of hedge fund strategies regarding the monitoring of systematic risk is highly nonlinear in extreme scenarios—especially during the subprime crisis.We find that countercyclical strategies have an investment technology which differs from procyclical ones.During crises,the former seek to capture non-traditional risk premia by deliberately increasing their systematic risk while the later focus more on minimizing risk.Our results suggest that the hedge fund strategies’betas respond more to illiquidity uncertainty than to illiquidity risk during crises.We find that illiquidity and VIX shocks are the major drivers of systemic risk in the hedge fund industry. 展开更多
关键词 hedge fund PROCYCLICALITY Illiquidity risk shock Illiquidity uncertainty shock Local projection model TVAR Optimal forecast Measurement errors
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COVID‑19 pandemic and the crude oil market risk:hedging options with non‑energy financial innovations 被引量:1
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作者 Afees A.Salisu Kingsley Obiora 《Financial Innovation》 2021年第1期722-740,共19页
This study examines the hedging effectiveness of financial innovations against crude oil investment risks,both before and during the COVID-19 pandemic.We focus on the non-energy exchange traded funds(ETFs)as proxies f... This study examines the hedging effectiveness of financial innovations against crude oil investment risks,both before and during the COVID-19 pandemic.We focus on the non-energy exchange traded funds(ETFs)as proxies for financial innovations given the potential positive correlation between energy variants and crude oil proxies.We employ a multivariate volatility modeling framework that accounts for important statistical features of the non-energy ETFs and oil price series in the computation of optimal weights and optimal hedging ratios.Results show evidence of hedging effectiveness for the financial innovations against oil market risks,with higher hedging performance observed during the pandemic.Overall,we show that sectoral financial innovations provide resilient investment options.Therefore,we propose that including the ETFs in an investment portfolio containing oil could improve risk-adjusted returns,especially in similar financial crisis as witnessed during the pandemic.In essence,our results are useful for investors in the global oil market seeking to maximize risk-adjusted returns when making investment decisions.Moreover,by exploring the role of structural breaks in the multivariate volatility framework,our attempts at establishing robustness for the results reveal that ignoring the same may lead to wrong conclusions about the hedging effectiveness. 展开更多
关键词 Pandemics Financial innovations Energy markets hedgING Optimal portfolio
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Improving Accuracy of Estimating Two-Qubit States with Hedged Maximum Likelihood 被引量:1
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作者 殷琪 项国勇 +1 位作者 李传锋 郭光灿 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期1-5,共5页
As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately... As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately, hedged maximum likelihood estimation (HMLE) [Phys. Rev. Lett. 105 (2010)200504] was proposed to avoid this problem. Here we study more details about this proposal in the two-qubit case and further improve its performance. We ameliorate the HMLE method by updating the hedging function based on the purity of the estimated state. Both performances of HMLE and ameliorated HMLE are demonstrated by numerical simulation and experimental implementation on the Werner states of polarization-entangled photons. 展开更多
关键词 MLE Improving Accuracy of Estimating Two-Qubit States with hedged Maximum Likelihood
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High Altitude Frogs (Rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability 被引量:1
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作者 Wei CHEN Liqing PENG +3 位作者 Lichun JIANG David A.PIKE Christopher R.FRIESEN Gregory BROWN 《Asian Herpetological Research》 SCIE CSCD 2018年第1期43-49,共7页
Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environm... Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species (Rana kukunoris) inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable (e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes), and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions (e.g., duration of the active season, food availability). Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes. 展开更多
关键词 altitude bet-hedging strategy environmental quality egg size within-clutch variation unpredictable environment
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A Critical Discourse Analysis of Hedges in Chinese and American Spokespersons’ Remarks at Press Conference 被引量:1
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作者 GAO Ting 《Journal of Literature and Art Studies》 2020年第7期584-590,共7页
Hedging is a communication strategy frequently used by the spokespersons at the press conference.This thesis intends to find out the ideologies hidden behind those hedges under the guidance of Fairclough’s three-dime... Hedging is a communication strategy frequently used by the spokespersons at the press conference.This thesis intends to find out the ideologies hidden behind those hedges under the guidance of Fairclough’s three-dimensional model.As a research method of linguistics,critical discourse analysis(CDA)aims to reveal the the relationship among language,power and ideology hidden behind the language.This thesis adopts Prince’classification criteria of hedges to identify and count the different types of hedges in the research data selected from Chinese and American government websites.The analysis is conducted at the following three steps:description,interpretation and explanation.The first stage is to recognize and count the hedges in two languages,then to find their similarities and differences and the last step is to find possible reasons for those similarities and differences and the ideologies behind the hedges.Analysis results show that differences in culture values and diplomatic ideology contribute to the different ideologies. 展开更多
关键词 critical discourse analysis spokesperson’s remarks hedgE Fairclough’s three-dimensional model IDEOLOGY
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Hedging in Discourse Analysis
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作者 肖欣 《海外英语》 2015年第12期232-234,共3页
In this article an attempt to enhance the awareness of hedging use in discourse analysis and academic writing is madeby analyzing hedges employed in two comparable texts.The discourse analysis is conducted from"c... In this article an attempt to enhance the awareness of hedging use in discourse analysis and academic writing is madeby analyzing hedges employed in two comparable texts.The discourse analysis is conducted from"content-oriented"hedges and"reader-oriented"hedges.The article suggests that hedging can dampen utterances and statements,weaken the force of what onesays and show politeness to the listeners or readers,which varies from different discourse styles of various genres.discourse marker;hedging;research article;news 展开更多
关键词 DISCOURSE MARKER hedgING research ARTICLE NEWS report
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A Corpus-based Contrastive Study on Hedging in English Business Cor-respondences between Chinese English Learners and Native Speakers
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作者 周敏仪 《海外英语》 2013年第1X期261-262,共2页
This is a corpus-based contrastive study projected to find out the differences in using hedges in English business corre spondences between Chinese English learners and native speakers.
关键词 hedgES CORPUS CONTRASTIVE study NS CEL
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Pragmatic Functions of Hedges in Business Letters
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作者 刘璐璐 《海外英语》 2013年第14期249-251,共3页
The aim of the present research to explore the hedges used English business letters. Several samples have been chosen to make qualitative study in order to achieve the goal of answering the following question: what ar... The aim of the present research to explore the hedges used English business letters. Several samples have been chosen to make qualitative study in order to achieve the goal of answering the following question: what are the pragmatic functions of hedges being used in business letters? After analyzing the samples, the conclusion could be came that the employment of hedges in business letters has three pragmatic functions-giving the right amount of information, being polite and self-production. 展开更多
关键词 hedgES BUSINESS LETTERS PRAGMATIC FUNCTION
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The Relative Ordering of Optimal Hedging Points in a Class of Failure Prone Manufacturing Systems
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作者 俞新贞 宋文忠 《Journal of Southeast University(English Edition)》 EI CAS 1997年第1期114-117,共4页
For a class of manufacturing systems with homogeneous Markov machine failure rates,the stationary probability distribution of the part surplus can be calculated for given tentative values of hedging points. Some prope... For a class of manufacturing systems with homogeneous Markov machine failure rates,the stationary probability distribution of the part surplus can be calculated for given tentative values of hedging points. Some properties on the ordering of optimal hedging points are obtained. 展开更多
关键词 MANUFACTURING SYSTEM MARKOV chain transition rate SYSTEM state hedgING point policy
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Price Fluctuation, Risk Hedge and Choice of Optimal Point
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作者 赵成珍 卜伟 宋锦玲 《Journal of Shanghai Jiaotong university(Science)》 EI 2016年第1期51-56,共6页
On the question of optimal hedge ratio, this paper firstly draws the chance to choose a market-entering point to the model. Using the replication principle of finance engineering, we make an assumed equity and get the... On the question of optimal hedge ratio, this paper firstly draws the chance to choose a market-entering point to the model. Using the replication principle of finance engineering, we make an assumed equity and get the optimal hedge ratio of the model, which gives the theoretical support to the practice. We should not only concern on the market-entering point, but also concern on the period of the hedge that still influences the effect of hedging. But only the period of hedging gives its affection if the time is relatively long. 展开更多
关键词 market-entering point hedging ratio replication principle
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