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Double Conditional Expectation 被引量:3
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作者 HUDi-he 《Wuhan University Journal of Natural Sciences》 CAS 2004年第6期851-857,共7页
The concept of double conditional expectation is introduced. A series of properties for the double conditional expectation are obtained several convergence theorems and Jensen inequality are proved. Finally we discuss... The concept of double conditional expectation is introduced. A series of properties for the double conditional expectation are obtained several convergence theorems and Jensen inequality are proved. Finally we discuss the special cases and application for double conditional expectation. Key words double conditional expectation - covergence theorem - Jensen inequality - branching chain in random environment CLC number O 211.6 Foundation item: Supported by the National Science Foundation of China (10371092) and the Foundation of Wuhan UniversityBiography: HU Di-he (1935-), male, Professor, research direction: stochastic processes and random fractals. 展开更多
关键词 double conditional expectation covergence theorem Jensen inequality branching chain in random environment
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L_p-CONTINUITY OF NONCOMMUTATIVE CONDITIONAL EXPECTATIONS
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作者 胡建 马聪变 侯友良 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期995-1002,共8页
Let (M,τ) be a noncommutative probability space, (Mn)n≥l a sequence of von Neumann subalgebras of M and N a von Neumann subalgebra of M. We introduce the notions of It-approach and orthogonal approach for (Mn)... Let (M,τ) be a noncommutative probability space, (Mn)n≥l a sequence of von Neumann subalgebras of M and N a von Neumann subalgebra of M. We introduce the notions of It-approach and orthogonal approach for (Mn)n≥1 and prove that ε(x|Mn)Lp→ε(x|N) for any x ∈ Lp(M) (1 ≤ p 〈 ∞) if and only if (Mn)n≥1 τ-approaches and orthogonally approaches N. 展开更多
关键词 von Neumann algebra TRACE conditional expectation orthogonal approach
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THE OPTIMALITY CONDITIONS OF NONCONVEXSET-VALUED VECTOR OPTIMIZATION 被引量:2
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作者 盛保怀 刘三阳 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期47-55,共9页
The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz Joh... The concepts of alpha-order Clarke's derivative, alpha-order Adjacent derivative and alpha-order G.Bouligand derivative of set-valued mappings are introduced, their properties are studied, with which the Fritz John optimality condition of set-valued vector optimization is established. Finally, under the assumption of pseudoconvexity, the optimality condition is proved to be sufficient. 展开更多
关键词 set-valued derivative optimality condition pseudoconvex set-valued mapping
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ON THE GENERALIZED FRITZ JOHN OPTIMALITY CONDITIONS OF VECTOR OPTIMIZATION WITH SET-VALUED MAPS UNDER BENSON PROPER EFFICIENCY 被引量:3
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第12期1444-1451,共8页
A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condit... A kind of tangent derivative and the concepts of strong and weak * pseudoconvexity for a set-valued map are introduced. By the standard separation theorems of the convex sets and cones the optimality Fritz John condition of set-valued optimization under Benson proper efficiency is established, its sufficience is discussed. The form of the optimality conditions obtained here completely tally with the classical results when the set-valued map is specialized to be a single-valued map. 展开更多
关键词 contingent tangent cone set-valued map Benson proper efficiency Fritz John condition
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KUHN-TUCKER CONDITION AND WOLFE DUALITY OF PREINVEX SET-VALUED OPTIMIZATION 被引量:2
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第12期1655-1664,共10页
The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function... The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function were introduced, from which the properties of the corresponding contingent cone and the alpha-order contingent derivative were studied. Finally, the optimality Kuhn-Tucker condition and the Wolfe duality theorem for the alpha-order S-preinvex set-valued optimization were presented with the help of the alpha-order contingent derivative. 展开更多
关键词 preinvex set-valued function contingent epiderivatives optimality conditions DUALITY
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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search
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作者 Xiao Liu Pingting Lin +2 位作者 Fan Bu Shaoling Zhuang Shoudao Huang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期32-42,共11页
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi... The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems. 展开更多
关键词 Generator optimization Gaussian Process Regression(GPR) conditional Likelihood Lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation
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Higher-order Optimality Conditions for Henig Effcient Solution in Set-valued Optimization under Cone-convexlike Maps
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作者 ZHANG Jian WANG Qi-lin 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期415-419,共5页
This paper deals with higher-order optimality conditions for Henig effcient solutions of set-valued optimization problems.By virtue of the higher-order tangent sets, necessary and suffcient conditions are obtained for... This paper deals with higher-order optimality conditions for Henig effcient solutions of set-valued optimization problems.By virtue of the higher-order tangent sets, necessary and suffcient conditions are obtained for Henig effcient solutions of set-valued optimization problems whose constraint condition is determined by a fixed set. 展开更多
关键词 higher-order contingent(adjacent)set Henig effcient solutions higher-order optimality conditions set-valued optimization
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OPTIONAL AND PREDICTABLE PROJECTIONS OF SET-VALUED MEASURABLE PROCESSES
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作者 Wang Rongmingof Statistcs,East China Normal Univ.,Shanghai 200062. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第3期323-329,共7页
In this paper,the optional and predictable projections of set-valued measurable processes are studied.The existence and uniqueness of optional and predictable projections of set-valued measurable processes are proved ... In this paper,the optional and predictable projections of set-valued measurable processes are studied.The existence and uniqueness of optional and predictable projections of set-valued measurable processes are proved under proper circumstances. 展开更多
关键词 set-valued conditional expectation essential(convex)closure optional projection predictable projection measurable processes.
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CONE-DIRECTED CONTINGENT DERIVATIVES AND GENERALIZED PREINVEX SET-VALUED OPTIMIZATION 被引量:10
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作者 丘京辉 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期211-218,共8页
By using cone-directed contingent derivatives, the unified necessary and sufficient optimality conditions are given for weakly and strongly minimal elements respectively in generalized preinvex set-valued optimization.
关键词 Preinvex set-valued optimization cone-directed contingent derivative optimality conditions
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Generalized cone-subconvexlike set-valued maps and applications to vector optimization 被引量:1
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作者 黄永伟 HUANG Yongwei 《Journal of Chongqing University》 CAS 2002年第2期67-71,共5页
The definitions of cone-subconvexlike set-valued maps and generalized cone-subconvexlike set-valued maps in topological vector spaces are defined by using the relative interiors of ordering cone. The relationships bet... The definitions of cone-subconvexlike set-valued maps and generalized cone-subconvexlike set-valued maps in topological vector spaces are defined by using the relative interiors of ordering cone. The relationships between the two classes of set-valued maps are investigated, and some properties of them are shown. A Gordan type alternative theorem under the assumption of generalized cone-subconvexlikeness of set-valued maps is proved by applying convex separation theorems involving the relative interiors in infinite dimensional spaces. Finally a necessary optimality condition theorem is shown for a general kind of set-valued vector optimization in a sense of weak E-minimizer. 展开更多
关键词 relative interiors generalized cone-subconvexlikeness set-valued vector optimization optimality conditions weak E-minimizer.
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An Upper Bound for Conditional Second Moment of the Solution of a SDE
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作者 Andriy Yurachkivsky 《Applied Mathematics》 2013年第1期135-143,共9页
Let be a filtration on some probability space and let denote the class of all -adapted -valued stochastic processes M such that for all t>s≥0 and the process is continuous (the conditional expectations are extende... Let be a filtration on some probability space and let denote the class of all -adapted -valued stochastic processes M such that for all t>s≥0 and the process is continuous (the conditional expectations are extended, so we do not demand that . It is shown that each is a locally square integrable martingale w. r. t. . Let X be the strong solution of the equation where , t is a continuous increasing process with -measurable values at all times, and Q is an -valued random function on , continuous in and -progressive at fixed x. Suppose also that there exists an -measurable in nonnegative random process Ψ such that, for all Then 展开更多
关键词 conditional expectation MARTINGALE Stochastic EQUATION
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Transmission Based Conditional Logistic Model for Testing Main and Interaction Effects
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作者 Caixia Li Peixing Li 《Open Journal of Statistics》 2021年第5期713-719,共7页
Transmission disequilibrium test (TDT) is a popular family based genetic association method. Under multiplicative assumption, a conditional logistic regression for matched pair, affected offspring with allele transmit... Transmission disequilibrium test (TDT) is a popular family based genetic association method. Under multiplicative assumption, a conditional logistic regression for matched pair, affected offspring with allele transmitted from parents and pseudo-offspring (control) with allele non-transmitted from parents, was built to detect the <span style="font-family:Verdana;">main </span><span style="font-family:Verdana;">effects of genes and gene-covariate interaction</span><span style="font-family:Verdana;">s</span><span style="font-family:;" "=""><span style="font-family:Verdana;">. When there exist genotype uncertainties, expectation-maximization (EM) algorithm was adopted to estimate the coefficients. The transmission model was applied to detect the association between M235T polymorphism in AGT gene and essential hypertension (ESH). Most of parents are not available in the 126 families from HongKong Chinese population. The results </span><span style="font-family:Verdana;">showed M235T is associat</span></span><span style="font-family:Verdana;">ed</span><span style="font-family:Verdana;"> with hypertension and there is interaction between M235T and the case’s sex. The allele T is higher risk for male than female</span><span style="font-family:Verdana;">.</span> 展开更多
关键词 Transmission Disequilibrium Test Gene-Covariate Interaction conditional Logistic Model expectation-Maximization Algorithm
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仿生嗅觉传感技术及在电力设备状态检测中的应用前景综述
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作者 段大鹏 盛戈皞 +3 位作者 任志刚 刘若溪 桂媛 王羽 《高压电器》 北大核心 2025年第1期1-11,共11页
电气设备的安全运行对电力系统的稳定性十分重要。近年来,仿生嗅觉传感技术是国内外研究的热点,仿生嗅觉传感技术已经成功应用于食品检验、检疫、搜救等领域。该技术也可以用于检测电气设备的缺陷或故障,通过检测电气设备金属导体及气... 电气设备的安全运行对电力系统的稳定性十分重要。近年来,仿生嗅觉传感技术是国内外研究的热点,仿生嗅觉传感技术已经成功应用于食品检验、检疫、搜救等领域。该技术也可以用于检测电气设备的缺陷或故障,通过检测电气设备金属导体及气、液或固态绝缘介质散发出的特有气味分子,进而识别设备的缺陷或故障,并可以同时联合视觉与听觉进行诊断分析。文中首先概述了仿生嗅觉传感技术的发展历程,阐述了三代仿生嗅觉传感技术的原理、技术特征和研究进展,并对其应用场景和发展方向进行了探讨。其次,从气、液、固3种状态绝缘介质的故障识别角度,对当前电力设备中的气体检测技术进行了总结与分析,提出了仿生嗅觉传感技术的适用场景和优势。最后,结合仿生嗅觉传感技术的发展和研究方向,对仿生嗅觉传感技术未来的应用前景和关键问题进行了分析,提出了未来仿生嗅觉传感技术的研究展望。 展开更多
关键词 仿生嗅觉 电力设备状态检测 气体识别 应用 展望
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A REMARK ON CONDITIONAL EXPECTATIONS
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作者 严加安 《Chinese Science Bulletin》 SCIE CAS 1990年第9期719-722,共4页
Let(Ω, J, P) be a probability space and э be a sub a-algebra of J. It is well known that for any non-negative J-measurable function X one can define the conditional expectation E[X[(?)] of X given (?). Therefore it ... Let(Ω, J, P) be a probability space and э be a sub a-algebra of J. It is well known that for any non-negative J-measurable function X one can define the conditional expectation E[X[(?)] of X given (?). Therefore it is natural to pose the following general definition of the conditional expectation. 展开更多
关键词 GENERALIZED conditional expectation Jensen’s inequality.
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ON CONDITIONAL EXPECTATION OPERATORS ON L(μ,X)(1≤p≤+∞,p≠2)
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作者 那啟元 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1990年第4期403-409,共7页
Some characterizations of the conditional expectation operators on Lebesgue-Bochnerspaces L_p(μ,X)are given,where 1≤p【∞,p≠2.Also an example is given to show thatthe characterizations of the conditional expectatio... Some characterizations of the conditional expectation operators on Lebesgue-Bochnerspaces L_p(μ,X)are given,where 1≤p【∞,p≠2.Also an example is given to show thatthe characterizations of the conditional expectation operators on L_p(μ,X)are differentfrom that on L_p(μ)_z Finally,a representation of the constant-preserving contractiveprojection on spaces L_p(μ,X)is got when 0【p【1. 展开更多
关键词 preserving expectation OPERATORS Radon conditional LEBESGUE UNIFORMLY GENERA 即夕 田滋
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Optimality conditions in set optimization employing higher-order radial derivatives
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作者 YU Guo-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第2期225-236,共12页
There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions... There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions for a constrained set-valued optimization problem in terms of higher-order radial derivatives. In the case of vector criterion, some optimality conditions are derived for isolated (weak) minimizers. With set criterion, necessary and sufficient optimality conditions are established for minimal solutions relative to lower set-order relation. 展开更多
关键词 higher-order radial derivative optimality conditions set-valued optimization vector criterion set criterion.
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Study of the Conditions of Formation and Forecast of the Perspective Areas of Hydrogen-Sulfide Water of Surkhandarya Depression
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作者 Rakhimjan Abdurazakovich Umurzakov Muzaffar Rakhmatovich Zhuraev Rustam Yunusovich Yusupov 《Open Journal of Geology》 2019年第4期213-225,共13页
Increase in requirement of hydrosulphuric water for improvement of the population set the task of identification of places of their possible congestion for hydrogeological service. Earlier detection of such congestion... Increase in requirement of hydrosulphuric water for improvement of the population set the task of identification of places of their possible congestion for hydrogeological service. Earlier detection of such congestions was accidental at well-drilling of different function. Therefore, development of new methodical approaches of search and allocation of perspective zones of their formation was required. It was for this purpose necessary to study in what conditions and what factors have an impact on formation of underground hydrosulphuric water. So far, definition of communication attempts only with separate geochemical signs was known. Results of studying of influence on formations of hydrosulphuric water of such factors as lithologic and facial in combination with oil-and-gas content, the geological and structural and hydrodynamic mode are given in this work. It is established that the main sign for formation of hydrosulphuric water is existence of evaporite thickness and hydrocarbon congestions. Besides, it is shown that small depth (up to 2 km) of their bedding has to be an indispensable condition and existence of explosive violation on which there has to be a water infiltration (a geological and structural factor). In the Surkhandarya region, the hydrodynamic mode caused by inclined bedding of aquifers was also one of essential factors. Active water is an exchange process with washing away (oxidation) sulfate of the containing thicknesses and subsequently, its restoration in interaction with hydrocarbons with formation of hydrosulphuric water is described. The technique is developed and the expected card of perspective zones of formation of hydrosulphuric water is constructed. 展开更多
关键词 Hydrosulfuric WATER Oil and Gas Complexes FORMATION conditIONS Factor Lithologic FACIES Geostructural HYDRODYNAMICS of Ground WATER expectED Map
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基于最优动态功率补偿的先进绝热压缩空气储能一次调频控制策略 被引量:2
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作者 崔森 陈来军 +2 位作者 陈思源 孙正堂 梅生伟 《高电压技术》 EI CAS CSCD 北大核心 2024年第6期2433-2441,I0001,共10页
随着大规模新能源接入电网,新型电力系统“低惯量、弱支撑”特征凸显,电网频率调节资源日益稀缺,系统频率稳定问题愈发严峻。先进绝热压缩空气储能(advanced adiabatic compressed air energy storage,AA-CAES)具有容量大、寿命长等优... 随着大规模新能源接入电网,新型电力系统“低惯量、弱支撑”特征凸显,电网频率调节资源日益稀缺,系统频率稳定问题愈发严峻。先进绝热压缩空气储能(advanced adiabatic compressed air energy storage,AA-CAES)具有容量大、寿命长等优势而受到广泛关注,但由于其储能和释能过程涉及气-热动态耦合过程,调频特性较为复杂,调频潜力还有待挖掘。因此,首先建立AA-CAES系统全工况动态仿真模型,进而基于期望频率动态曲线设计AA-CAES系统调频传递函数,优化目标传递函数关键参数,实现AA-CAES最小动态功率补偿下满足系统频率调节需求。最后通过仿真实验,验证了所提控制策略可优化AA-CAES调频容量的同时减小系统的稳态频率偏差与频率超调量,显著改善频率响应特性,为建设电网友好型AA-CAES电站提供技术支撑。 展开更多
关键词 先进绝热压缩空气储能 全工况动态建模 功率补偿 期望曲线 频率调节 调频容量
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共赢促进合作的认知计算机制:互惠中积极期望与社会奖赏的作用
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作者 吴小燕 付洪宇 +6 位作者 张腾飞 鲍东琪 胡捷 朱睿达 封春亮 古若雷 刘超 《心理学报》 CSSCI CSCD 北大核心 2024年第9期1299-1312,I0026-I0036,共25页
在社会互动中,人们常表现出有条件的合作行为,即只有在预期他人也合作时人们才愿意合作。当前该过程的认知机制尚不明确。本文采用多回合版本的囚徒困境范式,两项实验均表明个体的合作行为随合作者合作行为的提高而提高。认知计算模型... 在社会互动中,人们常表现出有条件的合作行为,即只有在预期他人也合作时人们才愿意合作。当前该过程的认知机制尚不明确。本文采用多回合版本的囚徒困境范式,两项实验均表明个体的合作行为随合作者合作行为的提高而提高。认知计算模型显示个体同时采用了一阶信念(只根据他人过去的行为)与二阶信念(既根据他人过去的行为,也考虑自己的行为对他人产生的影响)去更新他们对合作者的合作概率的期望。结果显示个体的有条件合作行为的提升由积极期望(即合作成功使得个体对合作者建立了积极的期望)与社会奖赏(由合作本身带来的额外奖励)共同驱动。这些结果揭示了有条件的合作行为的计算认知学习机制,阐明了积极期望和社会奖赏对合作的促进作用,能为社会中各领域合作的成功推动提供了重要的科学证据与参考价值。 展开更多
关键词 条件合作 社会奖赏 积极期望 认知计算建模 信念更新
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G-理论下的欧式向下敲出看涨期权定价
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作者 陈静瑶 张继超 +1 位作者 张会鑫 刘天泽 《北华大学学报(自然科学版)》 CAS 2024年第6期714-721,共8页
用G-几何布朗运动描述标的股票价格变化,假设波动率属于某一确定区间,通过G-Girsanov变换得到风险中性测度下欧式向下敲出看涨期权的定价区间。实验对比了布朗运动与G-布朗运动的路径,讨论了G-二次变差的参数对期权价格区间的影响,并对... 用G-几何布朗运动描述标的股票价格变化,假设波动率属于某一确定区间,通过G-Girsanov变换得到风险中性测度下欧式向下敲出看涨期权的定价区间。实验对比了布朗运动与G-布朗运动的路径,讨论了G-二次变差的参数对期权价格区间的影响,并对期权价格进行敏感性分析,验证了模型的合理性。 展开更多
关键词 波动率区间 G-条件期望 G-Girsanov变换 障碍期权
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