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71.
The European Union is approaching a point where it has to decide between two options: deepening political integration or reducing it. Economists tend to be sceptical. Many would prefer to reduce the scale of integration while returning more competences to member states. The debate, though, lacks a plausible vision for the path forward. Every stable currency union needs some kind of transfer mechanism. Once this notion is accepted, the installation of a “real” European Parliament with the power to raise taxes, particularly on capital income, should be considered.  相似文献   
72.
For a long list of investment “biases,” including lack of diversification, excessive trading, and the disposition effect, we find that genetic differences explain up to 45% of the remaining variation across individual investors, after controlling for observable individual characteristics. The evidence is consistent with a view that investment biases are manifestations of innate and evolutionary ancient features of human behavior. We find that work experience with finance reduces genetic predispositions to investment biases. Finally, we find that even genetically identical investors, who grew up in the same family environment, often differ substantially in their investment behaviors due to individual-specific experiences or events.  相似文献   
73.
The aim of this study was to examine injury events and risk-factors among Swedish adult eventing athletes. A cross-sectional study design with retrospective recording of 1-year sports-specific exposure and injury data was used. The invited study population consisted of all members of the Swedish Equestrian Federation with eventing as their primary discipline (n = 513). The participation rate was 70.0%. The total 1-year injury prevalence was 26.6%; the specific 1-year prevalence of traumatic injury was 19.3% and of overuse injury 10.9%. The incidence of traumatic injury events was 0.54 injury events/1000 eventing hours (95% confidence interval (CI), 0.35-0.73 injury events/1000 eventing hours) for novices and 0.35 injury events/1000 eventing hours for qualified riders (95% CI, 0.21-0.49 injury events/1000 eventing hours). A total of 27.9% of the traumatic injury events led to severe injuries (causing more than 3 weeks absence from riding). Attitude to risk-taking was the only factor predicting an athlete becoming injured (p = 0.023), and qualification level was the only risk factor for additional injuries among injured riders (p = 0.003). Our results suggest that injury prevention programs in eventing should also give attention to overuse injuries and that care should be taken when eventing athletes are licensed into higher qualification groups.  相似文献   
74.
The aim of the present paper is to present and evaluate a method for encouraging long-term thinking and considerations of a variety of scenarios in environmental policy processes. The Swedish environmental policy is based on 16 environmental objectives that national authorities are responsible for. They are evaluated annually and also in-depth every fourth year. Here we describe and explore a futures study project for introducing a more long-term thinking in the work with the environmental objectives, tested in the in-depth evaluation 2008. An experience was that it is difficult to design a collective scenario work in a case with a wide variety of objectives and with individuals with different backgrounds. However, this difficulty makes it even more important to incorporate futures studies in authorities work. Scenario work is often subcontracted, leading to a constant lack of futures studies competence and thinking at the authorities. Another experience is that despite the difficulties, experts at the authorities did start thinking more in terms of opportunities with futures studies. A general conclusion from the work was that there is an interest and need for futures studies at the authorities in charge of the environmental objectives. The possibly most important conclusion from this project was that the authorities need to build up their own competences in futures studies.  相似文献   
75.
76.
In this paper, the asymptotic decay of finite time ruin probabilities is studied. An insurance company is considered that faces heavy-tailed claims and makes investments in risky assets whose prices evolve according to quite general semimartingales. In this setting, the ruin problem corresponds to determining hitting probabilities for the solution to a randomly perturbed stochastic integral equation. A large deviation result for the hitting probabilities is derived that holds uniformly over a family of semimartingales. This result gives the asymptotic decay of finite time ruin probabilities under sufficiently conservative investment strategies, including ruin-minimizing strategies. In particular, as long as the insurance company invests sufficiently conservatively, the investment strategy has only a moderate impact on the asymptotics of the ruin probability.  相似文献   
77.
Regime-based asset allocation has been shown to add value over rebalancing to static weights and, in particular, reduce potential drawdowns by reacting to changes in market conditions. The predominant approach in previous studies has been to specify in advance a static decision rule for changing the allocation based on the state of financial markets or the economy. In this article, model predictive control (MPC) is used to dynamically optimize a portfolio based on forecasts of the mean and variance of financial returns from a hidden Markov model with time-varying parameters. There are computational advantages to using MPC when estimates of future returns are updated every time a new observation becomes available, since the optimal control actions are reconsidered anyway. MPC outperforms a static decision rule for changing the allocation and realizes both a higher return and a significantly lower risk than a buy-and-hold investment in various major stock market indices. This is after accounting for transaction costs, with a one-day delay in the implementation of allocation changes, and with zero-interest cash as the only alternative to the stock indices. Imposing a trading penalty that reduces the number of trades is found to increase the robustness of the approach.  相似文献   
78.
Interaction design is usually described as being concerned with interactions with and through artifacts but independent of a specific implementation. Design work has been characterized as a conversation between the designer and the situation and this conversation poses a particular challenge for interaction design as interactions can be elusive and difficult to describe. Moreover, current trends in interaction design introduce physical materials to a higher degree resulting in even more complex design situations. There is a lack of knowledge about how interaction designers, and especially students, address the very phenomenon of interaction. This study contributes by describing how interaction design students attempt to address aspects of interaction and by presenting an in-depth analysis in the context of an interactionary-type design exercise. The quantitative and qualitative findings showed that (1) the design students brought up aspects of interactivity and dynamics through talk and gestures but (2) a comprehensive design idea about interaction did not guide the design work and they were to a little degree engaged in planning sequences of interactions or interaction on a longer time scale, (3) using physical materials disrupted interaction design, and, (4) there was a lack of continuity when addressing interaction compared to how proposals about artifacts were pursued. As interaction is the core of interaction design, the findings are discussed in terms of how the immaterial design materials may “talk back” to designers. Practical strategies for how the observed phenomena could be constructively addressed within interaction design education are suggested.  相似文献   
79.
80.
We explore the efficacy of price and quantity controls in a dynamic setup in which the decisions of some agents are irreversible. The assumption of irreversibility is shown to improve the performance of a tax relative to that of a system of tradable quotas and significantly alter the equilibrium behavior of agents. We nevertheless conclude that taking into account the fact that agents’ decisions may be irreversible does not lead to policy implications significantly different from those reached in a simpler model in which irreversibility is ignored.  相似文献   
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