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991.
We reveal an interesting convex duality relationship between two problems: (a) minimizing the probability of lifetime ruin when the rate of consumption is stochastic and the individual can invest in a Black–Scholes financial market; (b) a controller-and-stopper problem, in which the controller controls the drift and volatility of a process in order to maximize a running reward based on that process, and the stopper chooses the time to stop the running reward and pays the controller a final amount at that time. Our primary goal is to show that the minimal probability of ruin, whose stochastic representation does not have a classical form as does the utility maximization problem (i.e., the objective’s dependence on the initial values of the state variables is implicit), is the unique classical solution of its Hamilton–Jacobi–Bellman (HJB) equation, which is a non-linear boundary-value problem. We establish our goal by exploiting the convex duality relationship between (a) and (b).  相似文献   
992.
We prove that, under very weak conditions, optimal financial products on complete markets are co-monotone with the reversed state price density. Optimality is meant in the sense of the maximization of an arbitrary preference model, e.g., expected utility theory or prospect theory. The proof is based on a result from transport theory. We apply the general result to specific situations, in particular the case of a market described by the Capital Asset Pricing Model or the Black–Scholes model, where we derive a generalization of the two-fund-separation theorem and give an extension to APT factor models and structured products with several underlyings. We use our results to derive a new approach to optimization in wealth management, based on a direct optimization of the return distribution of the portfolio. In particular, we show that optimal products can (essentially) be written as monotonic functions of the market return. We provide existence and nonexistence results for optimal products in this framework. Finally we apply our results to the study of bonus certificates, show that they are not optimal, and construct a cheaper product yielding the same return distribution.  相似文献   
993.
Creativity is acknowledged to be important for economic growth and as an everyday life-skill, however several influential reports have suggested that education could do more to harness creative talent. Creative cognition literature suggests the lack of creativity is at least partly the result of ‘fixation’ (difficulty in generating novel ideas due to imagination being ‘structured’ by existing knowledge). This paper focuses on the secondary (students aged 11–16 years) design and technology (D&T) context in the UK. Here we examine whether teacher practice can contribute to fixation by focusing on one specific facet of teacher practice in D&T; the use of product analysis to inform the generation of creative design ideas. Data is drawn from the preliminary phase of a research and intervention project from interviews with D&T teachers (N = 14), students (N = 126) and lesson observations (N = 10) and an analysis of documents and student work. Product analysis is widely used at different points in design projects but, as is shown, in all cases current practice can lead to fixation, as thinking is constrained down specific paths and tasks are at best at procedural rather than comprehension level. The implications of these findings and tentative ways forward for practitioners are discussed.  相似文献   
994.
Der Beitrag stellt Insurance-linked Securities (“ILS”) als Instrument des alternativen Risikotransfers dar und grenzt ILS von anderen Instrumenten des alternativen Risikotransfers ab.  相似文献   
995.
We analyze the forecasting ability of financial variables to predict the state of the Swiss business cycle up to eight quarters ahead. Overall, our results suggest that financial variables convey leading information for the prediction of business cycles, even when applied to a small open economy. However, we clearly find that model specifications need to be extended to include variables accounting for external shocks, such as exchange rates or international commodity prices. It also appears that the forecasting contribution of individual variables changes over time. Specifically, in the last two decades, stock market liquidity has replaced the term spread as the best single predictor.  相似文献   
996.
This paper investigates the problem of asymmetric information in Taiwan’s cancer insurance market. Through the survey data, we find evidence of adverse selection existing in this market. Furthermore, we collect additional information on the individual, and find that the individual’s family cancer history contains additional valuable information. It can not only more accurately predict the probability of contracting cancer, as well as predict the willingness to purchase extended cancer insurance, but it can also help to mitigate the severity of adverse selection in the insurance market.  相似文献   
997.
石墨电极消耗率是电炉炼钢生产的一个重要技术经济指标。近年来我厂1.5t电弧炉炼钢生产中,石墨电极消耗率呈现上升趋势。针对这一问题,我们实施现场攻关,发现电极折断消耗是石墨电极消耗大的主要原因。通过对电弧炉设备大修、改善炼钢环境、规范炉前操作行为,有效地解决了炼钢生产中电极折断消耗高的问题,使石墨电极消耗率从18.7kg/t降低到8.4kg/t,且取得了良好的技术效果和经济效益。  相似文献   
998.
This article presents a case study of a portfolio of individual long‐term insurance contracts sold by a Spanish mutual company. We describe the risk levels, the rating structure, and the implied cross‐subsidies on a portfolio of policies providing health, life, and long‐term care insurance. We show evidence of reclassification risk through the history of disability spells. We also analyze the lapse behavior and seek to provide a rationale for the portfolio’s dynamics. We discuss the lack of commitment from the policyholders (lapses) and from the mutual company (which took a run‐off decision). Finally, we draw conclusions regarding the design of such contracts.  相似文献   
999.
While researchers in the growing field of urban political ecology have given significant attention to the fragmented hydroscape that characterizes access to drinking water in the global South, so far the (re)production of other urban waters and its related power relations have been underexplored. This article seeks to contribute to filling this gap by exploring the everyday negotiations over access to urban water bodies, in particular ponds. These are understood as a composite resource that is simultaneously water, land and public space. This analysis draws on a case study from a small city in West Bengal, India, and is based primarily on data from open interviews with different actors with a stake in urban ponds. The article demonstrates that in a context of ambiguity of the statutory governance regime and fragmented control, the (re)production of the pondscape is embedded within complex relationships of power whereby social marginalization can be offset at least momentarily by local institutions such as neighbourhood clubs and political parties.  相似文献   
1000.
Virtual currencies are in vogue mainly due to two factors. First, as a protest against authority-driven monetary policy decisions and second, as alternatives to deficits in some monetary systems arising out of political instability or other causes. Assuming that virtual currencies indeed (partially) replace national currencies as payment vehicles, we attempt, in this article, to integrate the virtual currency supply and demand into the Keynesian money market framework. This article presents a few results for the central banks and outlines problems that may result for monetary policy formulation. Since this is the first such attempt to model a national money market as a combination of nationally-issued currency and globally-issued virtual currency, certain simplistic assumptions have been made. Nevertheless, the model offers directions on the impact of virtual currencies on the monetary system and the national money market. Additionally, the paper integrates the official standpoints of the European Central Bank and the Bank of England on this topic.  相似文献   
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