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71.
This study extends the literature on portfolio choice under prospect theory preferences by introducing a two-period life cycle model, where the sufficiently loss averse household decides on optimal consumption and investment in a portfolio with one risk-free and one risky asset. The optimal solution depends primarily on whether the household’s present value of the consumption reference levels is below, equal to, or above the present value of its endowment income. Reference levels below the endowment income are associated with the self-enhancement motive. In this case, the household avoids relative losses in consumption in any present or future state of nature (good or bad). As a result the degree of loss aversion does not directly affect optimal consumption and risk taking activity. Reference levels equal to the endowment income are associated with the belonging motive. An example would be a household comparing to others that belong to the same social class. In this case the household’s optimal consumption is the reference consumption and the household will not invest in the risky asset. Finally, reference levels above the endowment income are associated with the self-improvement motive (or high aspirations). For such high reference levels, households cannot avoid experiencing a relative loss in consumption, either now or in the future. As a result, loss aversion directly affects consumption and risky investment.  相似文献   
72.
We investigate the determinants of the demand for Japanese government bonds (JGBs) by commercial banks in Japan. In particular, by estimating portfolio equations for JGB demand and bank loans, based on a panel data set from the late 1990s to the 2000s, we rigorously test the popular assertion that the long stagnation of the real economy caused a shift in the portfolios of commercial banks from bank lending to JGBs. We find that the popular assertion is not empirically supported. Rather, the portfolio shift from loans to JGBs has been caused by a fall in the ratio of the loan rate to unit lending costs, or the bank’s price–cost margin for lending.  相似文献   
73.
This paper investigates volatility spillover in the Nigerian sovereign bond market arising from oil price shocks, using Vector Autoregressive Moving Average ‐ Asymmetric Generalized Autoregressive Conditional Heteroscedasticity (VARMA‐AGARCH) model. The paper covers the period March 22, 2011 to April 14, 2016 and makes use of the daily data of the Nigerian Sovereign Bond, Brent oil and West Texas Intermediate (WTI), respectively. We endogenously and sequentially detect structural break points using the test of Bai and Perron (2003) framework. In order to accurately estimate the model, we modify it by incorporating the break points into the VARMA‐AGARCH model, a process which if ignored would lead to model misspecification. The results obtained demonstrate a significant cross‐market volatility transmission between oil and sovereign bond market with ample sensitivity to structural breaks. The study also computes optimum weight portfolio and hedge ratio both with and without structural breaks and results equally indicate sensitivity to structural breaks.  相似文献   
74.
本文开创性的从省域经验证据上研究并证实了创业板与产业结构优化升级的正向促进关系,尤其更进一步指出了地方政府不当行为阻碍了创业板的产业结构调整作用.创业板作为我国产业结构优化战略的重要载体,其设立五年来规模稳定扩张且产业引领效应初步显现.尽管地方政府有其特殊的激励机制背景,但应该保持市场中立的态度参与创业板市场,同时政府还应该从产业结构划分、创业板市场机制完善以及市场开放多方面进行改革.  相似文献   
75.
研究目的:从居民的通勤行为特征中寻求小城镇土地利用格局优化路径,为产城融合的实现提供理论支持。研究方法:构建通勤流矩阵,运用Arc GIS路径分析测算通勤距离,并通过缓冲区分析通勤距离在空间上的特征,并与土地利用类型进行对比分析,同时建立通勤距离与社会经济因素的回归方程,分析通勤距离的影响因素。研究结果:小城镇通勤方式以便捷型工具为主,通勤高峰集中于上下班,通勤距离随着城镇化和工业化水平的提高,短距离占比增大。主要结论:在城镇化和工业化发展较快的区域,短距离通勤集聚更具有"同心圆"特征,核心力更强。工业化带动的聚集结构呈现出"条带形"态势,与区域工业布局结构有较密切的关系,也与城镇化和工业化扩增融合有关。短距离通勤集聚区会随着城镇化水平的提高而由"双核"向"单核"结构发展,并针对以上问题提出了相应的对策。  相似文献   
76.
负值PBGT切换技术的实现和分层分级算法相似,但比分层分级算法更加灵活,它是移动通信系统中非常重要的技术。现通过工程实践多次使用网络优化工具设置负值PBGT切换参数,实现在双频网优化上的应用,可以避免乒乓切换引起掉话,该技术的应用有重要的现实意义。  相似文献   
77.
裴志 《价值工程》2014,(8):128-130
价值工程作为一种将功能与成本、技术与经济相结合而进行技术经济评价的方法,又称为价值分析。本文通过结合地下管线探测项目的具体实例,探讨了在具体的施工过程中,为了在降低工程成本的同时能够有效的保证施工工程的质量和进度,如何采用价值工程的方法选择以及优化施工组织设计的方案。实践证明,在施工项目中应用价值工程的方法不仅能够完善施工方案,还能有效确保施工进度并且能够有效提高利润,最重要的是还能够很好的保证施工质量。  相似文献   
78.
Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.  相似文献   
79.
80.
The traditional mean–variance approach has been complemented by alternative theories that use risk measures different from standard deviation of returns or involve additional distributional features of returns like skewness and kurtosis. We propose a portfolio choice model that combines different distributional characteristics of the returns in the decision-making making process, considering preferences of investors which are modeled as non-statistical uncertainties of investors using fuzzy theory. We use 20 stocks of the S&P500 from January 2013 to December 2017. We assess the obtained portfolios’ performance, and the diversified behavioral portfolios outperform than the mean–variance portfolio. This methodological proposal can be seen as a strong managerial tool to make investment portfolio decisions.  相似文献   
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