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41.
In this paper, the expression for the cost of capital is derived when capacity expansion investments and replacement investments exhibit differences in their effective prices. It is shown that the cost of capital derived by perturbing the optimal stock path should be constructed under an opportunity cost criterion.  相似文献   
42.
In this paper we introduce an asymmetric model of continuous electricity auctions with limited production capacity and bounded supply functions. The strategic bidding is studied with this model by means of an electricity market game. We prove that for every electricity market game with continuous cost functions a mixed-strategy Nash equilibrium always exists. In particular, we focus on the behavior of producers in the Spanish electricity market. We consider a very simple form for the Spanish electricity market: an oligopoly consisting just of independent hydro-electric power production units in a single wet period. We show that a pure-strategy Nash equilibrium for the Spanish electricity market game always exists.  相似文献   
43.
In this paper, we present a bilevel programming formulation for the problem of strategic bidding under uncertainty in a wholesale energy market (WEM), where the economic remuneration of each generator depends on the ability of its own management to submit price and quantity bids. The leader of the bilevel problem consists of one among a group of competing generators and the follower is the electric system operator. The capability of the agent represented by the leader to affect the market price is considered by the model. We propose two solution approaches for this non-convex problem. The first one is a heuristic procedure whose efficiency is confirmed through comparisons with the optimal solutions for some instances of the problem. These optimal solutions are obtained by the second approach proposed, which consists of a mixed integer reformulation of the bilevel model. The heuristic proposed is also compared to standard solvers for nonlinearly constrained optimization problems. The application of the procedures is illustrated in case studies with configurations derived from the Brazilian power system.  相似文献   
44.
技术市场聚类和预测   总被引:1,自引:0,他引:1  
李柏年 《运筹与管理》2005,14(2):101-104
本依据1993~2000年全国及各省、市、自治区技术市场成交额,用聚类分析的方法分析了我国技术市场的发展状况,进而利用最小二乘法建立了我国技术市场的预测模型。实例计算表明模型是有效的。  相似文献   
45.
The notion of density of a finite set is introduced. We prove a general theorem of set theory which refines the Gibbs, Bose-Einstein, and Pareto distributions as well as the Zipf law.  相似文献   
46.
Single–valued solutions for the case of two-sided market games without product differentiation, also known as Böhm–Bawerk horse market games, are analyzed. The nucleolus is proved to coincide with the τ value, and is thus the midpoint of the core. The Shapley value is in the core only if the game is a square glove market, and in this case also coincides with the two aforementioned solutions.Institutional support from research grants BEC 2002-00642, FEDER and SGR2001-0029 is gratefully acknowledged  相似文献   
47.
夏少刚  申树斌 《经济数学》2005,22(2):168-171
本文通过构建一个关于企业融资与经济增长的理论模型对融资收缩形成的内在机理进行了揭示.  相似文献   
48.
Portfolio Selection Problem with Minimax Type Risk Function   总被引:3,自引:0,他引:3  
The investor's preference in risk estimation of portfolio selection problems is important as it influences investment strategies. In this paper a minimax risk criterion is considered. Specifically, the investor aims to restrict the standard deviation for each of the available stocks. The corresponding portfolio optimization problem is formulated as a linear program. Hence it can be implemented easily. A capital asset pricing model between the market portfolio and each individual return for this model is established using nonsmooth optimization methods. Some numerical examples are given to illustrate our approach for the risk estimation.  相似文献   
49.
基本面价值加权投资组合是近年来在美国兴起的新型投资理论和技术.其基础是噪声市场假说和价格回归价值。本文回顾了基本面投资组合的相关文献,解释了其建立的理论基础和模型.本文还根据平滑市值权重技术,构建了基于中国股票市场的基本面投资组合,并和传统的市值加权投资组合进行比较。本文的主要结论是,中国市场1992年到2002年和美国市场类似呈现平稳价格噪声,基本面投资组合总体优于市值加权组合.股权分置改革初期市场低落,市场价格过度低估基本面价值,市值组合占优势。2005年下半年来股市呈现一定泡沫特征,市场价格对基本面价值有过度高估趋势,间接地证明了相关部门对股市过热的警告和监管是合理的.  相似文献   
50.
The paper demonstrates conceptual parallels and relationships between intellectual capital measurement methods and the evaluation of quality in clinical laboratories in the Slovak Republic. It explores further the contextual links of those parallels with the tangibility (or intangibility) of quality indicators of laboratory diagnostics. It also highlights the problems which laboratory staff in Slovakia are confronted with. Presented at the conference Quality in the Spotlight, March 2007, Antwerp, Belgium.  相似文献   
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