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991.
992.
We analyze security price formation in a dynamic setting in which long-lived dealers repeatedly compete for the opportunity to trade with short-lived retail traders. We characterize equilibria in which dealers’ pricing strategies are optimal irrespective of the private information that each dealer may possess. Thus, our model’s predictions are robust to different specifications of the dealers’ information structure. These equilibria reconcile, in a unified and parsimonious framework, price dynamics that are reminiscent of well-known stylized facts: excess price volatility, price to trading flow correlation, stochastic volatility and inventory-related trading.  相似文献   
993.
We consider the problem of simulating tail loss probabilities and expected losses conditioned on exceeding a large threshold (expected shortfall) for credit portfolios. Our new idea, called the geometric shortcut, allows an efficient simulation for the case of independent obligors. It is even possible to show that, when the average default probability tends to zero, its asymptotic efficiency is higher than that of the naive algorithm. The geometric shortcut is also useful for models with dependent obligors and can be used for dependence structures modeled with arbitrary copulae. The paper contains the details for simulating the risk of the normal copula credit risk model by combining outer importance sampling with the geometric shortcut. Numerical results show that the new method is efficient in assessing tail loss probabilities and expected shortfall for credit risk portfolios. The new method outperforms all known methods, especially for credit portfolios consisting of weakly correlated obligors and for evaluating the tail loss probabilities at many thresholds in a single simulation run.  相似文献   
994.
Abstract

In einer früheren Note habe ieh versucht, eine Methode zur Konstruktion abgestufter Sterbliehkeitstafeln zu finden, welche dazu geeignet wären, bei der Abschätzung von Prämien für nicht normale Risiken das versicherungstechnische Material zu liefern. Ich hatte zu diesem Zweek für die betreffende Krankheit, als welche in erster Linie und als Beispiel die Tuberkulose gewählt wurde, zunächst die Klasse P definiert, welehe aus allen Individuen besteht, die als Todesursache die Tuberkulose anfweisen werden. Die reziproke Klasse wurde mit S bezeiehnet. Für diese beiden Klassen lassen sich mit Hilfe der schwedischen Todesursachenstatistik die Todesfalls wahrscheinlichkeiten Px und P x in den verschiedenen Altersjahren x annähernd bestimmen.  相似文献   
995.
Swedish legislation requires that any owner or user of a building maintain a reasonable level of fire protection measures to ensure the safety of all people located in the building. If a building, in the wake of a fire, in court is determined not to have had a reasonable fire protection, the blame will likewise be assigned to the building owner or user. Using the perspective of risk governance, this study aims at analysing how regulation and stakeholders interact to maintain a specific level of fire protection in hotels. The focus is on identifying problems and frictions that have emerged from the complex relationships, and differences of interests, between the different stakeholders. Based on a stakeholder analysis, 11 respondents were selected for an interview study. The main problems identified in the analysis are that there are ambiguities for the individual hotel owner to know whether her or his fire protection measures are reasonable according to the law, that the system has emerged without clear political goals, problems related to the process of local supervision, that the ambiguous situation gives rise to opportunities of other stakeholders to claim the definition of what counts as a reasonable extent, and the ethical problems associated with convicting a single individual for failure in a complex multi-actor system.  相似文献   
996.
Existing methodologies and practices do not provide enough possibility for online monitoring and assessment of emerging risks occurring as a result of a change in technology, product, operating conditions, as well as in organization of activities in conventional industrial plants. Typical today’s off and online methods and corresponding software packages are used as risk assessment methods, while various risk aspects (such as: process risks, process equipment integrity risks, organizational risks, and health and environmental risks) are being assessed and treated independently. However, it is clear that risk assessment and making decisions in line with that has to be based on information collected from different (independent) sources in online mode. Also, the fact that additional risks in operations may occur due to unexpected changes in technology, accidents or unexpected process equipment degradation should be taken into account. When monitoring and process management systems are being designed and developed, only the process aspect and process risk are usually analyzed, while other risk aspects are not taken into account (like health and environmental risks). A new approach, to be presented in this paper, provides a possibility of online monitoring and assessment of risks (e.g. in petrochemical industry, power industry, etc.).  相似文献   
997.
Issues concerning risks in the military have gained increased attention within the Swedish Armed Forces, particularly relating to the new focus on an all voluntary force participating in international missions. Military activities inevitably include an element of calculated risk-taking, while at the same time the unnecessary taking of risks must be minimized. Within the context of the specific mission and situation, a number of factors relating to demographic variables, traits and beliefs may influence individual inclinations towards risk behaviour. The purpose of this study was to examine the relationship between such factors and individual risk propensity. Data were collected from two samples of Swedish soldiers and officers. Examining demographic variables, negative safety values and risk propensity were found to decrease with age, while men demonstrated a more sceptical view of safety measures and a higher risk propensity than women. The trait known as lack of deliberation, reflecting an inability to think ahead and foresee consequences, was positively related to risk propensity. A more sceptical view of safety was shown to be associated with a higher sense of personal invincibility and together with lack of deliberation predicted variations in danger-seeking scores. The distinction between functional and non-functional risk-taking is discussed on the basis of the relationships found in the study. Implications for recruitment to the military as well as for training and leadership are suggested, emphasizing the need for military leaders to balance their leadership in terms of safety-oriented and risk-promoting behaviours.  相似文献   
998.
Within the German welfare system, recipients’ heating expenditures are generally fully covered by the government. This paper empirically tests the hypothesis that households receiving welfare payments turn to overconsumption of residential space heating. We use micro‐data from two different data sources to explore whether the conditional heating expenditures of these households differ significantly from those of other households. Our empirical findings suggest that even when controlling for a range of other factors, this is indeed the case, as their heating expenditures lie about 7–8 per cent above those of other households. These results are fairly robust to sensitivity analyses. Comparing the results with those for a control group, expenditures for heating are still more than 5 per cent higher. Our results imply that there is potential scope for cost savings if this policy is changed.  相似文献   
999.
Due to changing customer demands Social Networks become increasingly important in insurance business life. This study provides a comprehensive analysis of both the traditional and new approaches of Social Network research. Based on this analysis we present categorized implications that show evidence for future research. We take up the research question from the category “communication and marketing” in order to experimentally investigate different kinds of customer communication in Social Networks. Our results show that the kind of customer communication has an impact on the willingness to comply. Thus, the kind of customer communication could be a critical criterion for the success of an insurance company in Social Networks.  相似文献   
1000.
What is the catastrophe risk a life insurance company faces? What is the correct price of a catastrophe cover? During a review of the current standard model, due to Strickler, we found that this model has some serious shortcomings. We therefore present a new model for the pricing of catastrophe excess of loss cover (Cat XL). The new model for annual claim cost C is based on a compound Poisson process of catastrophe costs. To evaluate the distribution of the cost of each catastrophe, we use the Peaks Over Threshold model for the total number of lost lives in each catastrophe and the beta binomial model for the proportion of these corresponding to customers of the insurance company. To be able to estimate the parameters of the model, international and Swedish data were collected and compiled, listing accidents claiming at least twenty and four lives, respectively. Fitting the new model to data, we find the fit to be good. Finally we give the price of a Cat XL contract and perform a sensitivity analysis of how some of the parameters affect the expected value and standard deviation of the cost and thus the price.  相似文献   
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