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991.
992.
从行为金融学的角度考虑投资者损失厌恶的心理特征,建立预期效用最大化的动态损失厌恶投资组合优化模型。以我国股票市场为依托,将市场分为上升、下降和盘整三种状态,研究动态损失厌恶投资组合模型的最优资产配置和绩效表现,并与静态损失厌恶投资组合模型、M-V投资组合模型和CVaR投资组合模型进行比较。最后,在具有交易成本的条件下对动态模型进行稳健性检验。得出结论:不同情况下,动态损失厌恶投资者具有不同的最优资产配置比例,且动态损失厌恶投资组合模型明显优于静态模型、M-V投资组合模型和CVaR投资组合模型。  相似文献   
993.
This study integrated risk‐benefit analysis with prospect theory with the overall objective of identifying the type of management behavior represented by farmers’ choices of mastitis control options (MCOs). Two exploratory factor analyses, based on 163 and 175 Swedish farmers, respectively, highlighted attitudes to MCOs related to: (1) grouping cows and applying milking order to prevent spread of existing infection and (2) working in a precautionary way to prevent mastitis occurring. This was interpreted as being based on (1) reactive management behavior on detection of udder‐health problems in individual cows and (2) proactive management behavior to prevent mastitis developing. Farmers’ assessments of these MCOs were found to be based on asymmetrical evaluations of risks and benefits, suggesting that farmers’ management behavior depends on their individual reference point. In particular, attitudes to MCOs related to grouping cows and applying milking order to prevent the spread of mastitis once infected cows were detected were stronger in the risk domain than in the benefit domain, in accordance with loss aversion. In contrast, attitudes to MCOs related to working in a precautionary way to prevent cows from becoming infected in the first place were stronger in the benefit domain than in the risk domain, in accordance with reverse loss aversion. These findings are of practical importance for farmers and agribusiness and in public health protection work to reduce the current extensive use of antibiotics in dairy herds.  相似文献   
994.
产学研协同创新体现了系统集成的思想,本文以协同学为基础,从自组织理论视角分析了高校创新能力在产学研协同创新过程中的动态演化规律。研究表明:复杂性科学可以有效地解决公共管理问题的不确定性,本文以具有自组织特征的"B-Z"反应模型为基础,建立了高校知识生产能力、知识传播能力和知识转移能力构成的Logistic模型,通过稳定性分析与仿真模拟,讨论了高校三个能力子系统在产学研协同创新过程中的演化规律,并进一步确定了主导能力要素的序参量模型,并且对我国31所高校在产学研协同创新过程中的演化规律进行了验证性实证分析。本文的研究为我国研究型大学通过调整内部能力结构促进产学研协同创新提供了定量的分析视角与科学的政策讨论依据。  相似文献   
995.
We consider firms that feature their products on the Internet but take orders offline. Click and order data are disjoint on such non‐transactional websites, and their matching is error‐prone. Yet, their time separation may allow the firm to react and improve its tactical planning. We introduce a dynamic decision support model that augments the classic inventory planning model with additional clickstream state variables. Using a novel data set of matched online clickstream and offline purchasing data, we identify statistically significant clickstream variables and empirically investigate the value of clickstream tracking on non‐transactional websites to improve inventory management. We show that the noisy clickstream data is statistically significant to predict the propensity, amount, and timing of offline orders. A counterfactual analysis shows that using the demand information extracted from the clickstream data can reduce the inventory holding and backordering cost by 3% to 5% in our data set.  相似文献   
996.
Rapid advances of information technology in recent years have enabled both the manufacturers and the retailers to operate their own Internet channels. In this study, we investigate the interaction between the capabilities of introducing the Internet channels, the pricing strategies, and the channel structure. We classify consumers into two segments: grocery shoppers attach a higher utility from purchasing through the physical channel, whereas a priori Internet shoppers prefer purchasing online. We find that when the Internet shoppers are either highly profitable or fairly unimportant, the manufacturer prefers to facilitate the channel separation either through his own Internet channel or the retailer's. In the intermediate region, however, the manufacturer encroaches the grocery shoppers and steals the demand from the retailer's physical channel. With horizontal competition between retailers, a priori symmetric retailers may adopt different channel strategies as a stable market equilibrium. The manufacturer may willingly give up his Internet channel and leverage on the retailer competition. When the manufacturer sells through an online e‐tailer, Internet shoppers may be induced to purchase through the physical channel. This reverse encroachment strategy emerges because selling through the e‐tailer leads to a more severe double marginalization problem.  相似文献   
997.
Humanitarian supply chains involve many different entities, such as government, military, private, and non‐governmental organizations and individuals. Well‐coordinated interactions between entities can lead to synergies and improved humanitarian outcomes. Information technology (IT) tools can help facilitate collaboration, but cost and other barriers have limited their use. We document the use of an IT tool to improve last‐mile supply distribution and data management in one of many camps for internally displaced persons after the January 2010 earthquake in Haiti, and we describe other current uses of technology in camp management. Motivated by these examples and the interest among humanitarian organizations in expanding the use of such tools to facilitate coordination, we introduce a cooperative game theory model and explore insights about the conditions under which multi‐agency coordination is feasible and desirable. We also outline an agenda for future research in the area of technology‐enabled collaboration in the humanitarian sector.  相似文献   
998.
R&D alliances and outsourcing elements of the new product development process are now commonplace practices among many firms. However, little previous work has examined how these organizational choices influence project knowledge and learning. Based on a comparison of three new product development projects in the software industry, this paper examines how task partitioning in the project influences learning and knowledge development within the firm. The paper suggests that internal development projects encourage synthetic learning and development of architectural and tacit knowledge; in contrast, outsourcing and joint ventures encourage analytic learning and development of component and explicit knowledge.  相似文献   
999.
It is well known that standard asymptotic theory is not applicable or is very unreliable in models with identification problems or weak instruments. One possible way out consists of using a variant of the Anderson–Rubin ((1949), AR) procedure. The latter allows one to build exact tests and confidence sets only for the full vector of the coefficients of the endogenous explanatory variables in a structural equation, but not for individual coefficients. This problem may in principle be overcome by using projection methods (Dufour (1997), Dufour and Jasiak (2001)). At first sight, however, this technique requires the application of costly numerical algorithms. In this paper, we give a general necessary and sufficient condition that allows one to check whether an AR‐type confidence set is bounded. Furthermore, we provide an analytic solution to the problem of building projection‐based confidence sets from AR‐type confidence sets. The latter involves the geometric properties of “quadrics” and can be viewed as an extension of usual confidence intervals and ellipsoids. Only least squares techniques are needed to build the confidence intervals.  相似文献   
1000.
零售市场价格策略的演化博弈分析   总被引:1,自引:0,他引:1  
基于一个三阶段Hotelling博弈模型:位于[0,1]线性城市两端的零售A和B第一阶段同时选择价格策略变量,第二阶段确定价格的大小,第三阶段由消费者选择零售商。应用演化博弈论进行研究,分析了零售市场价格策略的演化稳定性。  相似文献   
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