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991.
A framework underlying various models that measure the credit risk of a portfolio is extended in this paper to allow the integration of credit risk with a range of market risks using Monte Carlo simulation. A structural model is proposed that allows interest rates to be stochastic and provides closed-form expressions for the market value of a firm's equity and its probability of default. This model is embedded within the integrated framework and the general approach illustrated by measuring the risk of a foreign exchange forward when there is a significant probability of default by the counterparty. For this example moving from a market risk calculation to an integrated risk calculation reduces the expected future value of the instrument by an amount that could not be calculated using the common pre-settlement exposure technique for estimating the credit risk of a derivative.  相似文献   
992.
993.
Flood risk insurance can be an effective tool in assisting the restoration of damaged property after a flood event and sustaining communities through difficult times. It can also form part of a wider flood risk management strategy. In the light of recent flood events in the UK and in the context of changing property insurance markets, the universal cover previously enjoyed by floodplain residents has been called into question. Conflicting media and industry views leave the floodplain resident and the wider community in confusion. A survey of floodplain residents in England regarding their experience with flooding and flood insurance in England has been undertaken. The results reveal that some floodplain residents do indeed encounter difficulties when seeking insurance for their homes. However, despite the risk‐averse policies of some insurers, availability of insurance is still strong in both at‐risk and previously flooded locations. Success in gaining insurance may lead to complacency among residents who see no advantage in pursuing other, more costly, damage mitigation actions. As a tool in risk management, therefore, the market is prevented from realising its potential by competition, which results in a lack of a consistent approach, rewards homeowners' search strategies and reduces information flow.  相似文献   
994.
This paper argues that dividend yield stock return predictability is time-varying. We conjecture that such time-variation is linked to the business cycle. Employing monthly data for US sector portfolios we estimate 5-year rolling fixed window predictive regressions. The resulting series of time-varying predictive coefficients is regressed on industrial production growth and a recession dummy. Our results support the view of a negative relationship between predictability and output growth. That is the strength of the predictive relationship between returns and the dividend yield is stronger during contractionary periods, while during expansions the magnitude of the relationship declines.  相似文献   
995.
We apply the concept of free random variables to doubly correlated (Gaussian) Wishart random matrix models, appearing, for example, in a multivariate analysis of financial time series, and displaying both inter-asset cross-covariances and temporal auto-covariances. We give a comprehensive introduction to the rich financial reality behind such models. We explain in an elementary way the main techniques of free random variables calculus, with a view to promoting them in the quantitative finance community. We apply our findings to tackle several financially relevant problems, such as a universe of assets displaying exponentially decaying temporal covariances, or the exponentially weighted moving average, both with an arbitrary structure of cross-covariances.  相似文献   
996.
Abstract

This study sets out a backtesting framework applicable to the multiperiod-ahead forecasts from stochastic mortality models and uses it to evaluate the forecasting performance of six different stochastic mortality models applied to English & Welsh male mortality data. The models considered are the following: Lee-Carter’s 1992 one-factor model; a version of Renshaw-Haberman’s 2006 extension of the Lee-Carter model to allow for a cohort effect; the age-period-cohort model, which is a simplified version of Renshaw-Haberman; Cairns, Blake, and Dowd’s 2006 two-factor model; and two generalized versions of the last named with an added cohort effect. For the data set used herein, the results from applying this methodology suggest that the models perform adequately by most backtests and that prediction intervals that incorporate parameter uncertainty are wider than those that do not. We also find little difference between the performances of five of the models, but the remaining model shows considerable forecast instability.  相似文献   
997.
Abstract

The objective of this paper is to investigate dynamic properties of age trajectories of physiological indices and their effects on mortality risk and longevity using longitudinal data on more than 5,000 individuals collected in biennial examinations of the Framingham Heart Study (FHS) original cohort during about 50 subsequent years of follow-up. We first performed empirical analyses of the FHS longitudinal data. We evaluated average age trajectories of indices describing physiological states for different groups of individuals and established their connections with mortality risk. These indices include body mass index, diastolic blood pressure, pulse pressure, pulse rate, level of blood glucose, hematocrit, and serum cholesterol. To be able to investigate dynamic mechanisms responsible for changes in the aging human organisms using available longitudinal data, we further developed a stochastic process model of human mortality and aging, by including in it the notions of “physiological norms,” “allostatic adaptation and allostatic load,” “stress resistance,” and other characteristics associated with the internal process of aging and the effects of external disturbances. In this model, the persistent deviation of physiological indices from their normal values contributes to an increase in morbidity and mortality risks. We used the stochastic process model in the statistical analyses of longitudinal FHS data. We found that different indices have different average age patterns and different dynamic properties. We also found that age trajectories of long-lived individuals differ from those of the shorter-lived members of the FHS original cohort for both sexes. Using methods of statistical modeling, we evaluated “normal” age trajectories of physiological indices and the dynamic effects of allostatic adaptation. The model allows for evaluating average patterns of aging-related decline in stress resistance. This effect is captured by the narrowing of the U-shaped mortality risk (considered a function of physiological state) with age. We showed that individual indices and their rates of change with age, as well as other measures of individual variability, manifested during the life course are important contributors to mortality risks. The advantages and limitations of the approach are discussed.  相似文献   
998.
Abstract

In recent years, the validity of the weak form efficient market hypothesis (EMH) has been called into question as several studies have uncovered evidence that technical trading rules have predictive ability with respect to both developed and emerging stock market indices. This study analyses the forecasting power of 2 of the most popular trading rules using index data for a selection of 11 European stock markets over the January 1991 to December 2000 period. The findings indicate that the emerging markets included in this paper are informationally inefficient; these markets displayed some degree of predictability in their share returns, although the developed markets did not. Furthermore, the results point to large differences in the performance of the rules examined; while small size filters consistently outperformed the buy-and-hold strategy in the emerging markets examined even after the consideration of transaction costs, the performance of the moving average rules was erratic and varied dramatically from market to market.  相似文献   
999.
The paper discusses excess returns within four Scandinavian stock markets and also how Scandinavian returns are related to the returns in non-Scandinavian markets. Some underlying reasons for the observed economically weak relationships between markets are reviewed. Moreover, some reasons why the interrelationships between markets can be expected to increase in the future are provided.  相似文献   
1000.
This paper reports on the results of a survey and qualitative analysis on the teaching of ‘Basic Design’ in schools of design and architecture located in 22 countries. In the context of this research work, Basic Design means the teaching and learning of design fundamentals that may also be commonly referred to as the Principles of Two- and Three-dimensional Design. The body of knowledge associated with Basic Design may be regarded as part of the general theory of teaching and learning design as practiced in many design schools and which has its origins in the classical design schools such as the Bauhaus. In the author’s perception and practice, the pedagogy of Basic Design promotes a holistic, creative and experimental methodology that develops the learning style and cognitive abilities of students with respect to the fundamental principles of design. This includes an understanding of the elements of shape, colour, texture, light, and rhythm in a manner complementary but usually unrelated to the common design methods teaching approach. As is well known among design practitioners, including architects and industrial designers, a deep understanding of the purpose of these fundamental design elements and principles is still relevant to contemporary design practice. The main objective of the research described in this paper was to determine the status and development of Basic Design pedagogy in a significant number of contemporary design schools. On the basis of the results of two surveys conducted in 2001–2002, this paper will identify and illustrate interesting aspects concerning the programmes and organisation of courses delivered by teachers of ‘Basic Design’. This work will also survey the viewpoints of Basic Design teachers in elementary years of design courses and of those teaching design through projects during the subsequent years of the same courses. Interestingly, the design project teachers surveyed in this research expressed a desire to be more involved in the teaching of Basic Design fundamentals which indicates strongly that Basic Design principles are still relevant in contemporary design education terms as they have ever been and that more research is needed in order to better understand and apply the related pedagogy.  相似文献   
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