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941.
The implied volatility skew has received relatively little attention in the literature on short-term asymptotics for financial models with jumps, despite its importance in model selection and calibration. We rectify this by providing high order asymptotic expansions for the at-the-money implied volatility skew, under a rich class of stochastic volatility models with independent stable-like jumps of infinite variation. The case of a pure-jump stable-like Lévy model is also considered under the minimal possible conditions for the resulting expansion to be well defined. Unlike recent results for “near-the-money” option prices and implied volatility, the results herein aid in understanding how the implied volatility smile near expiry is affected by important features of the continuous component, such as the leverage and vol-of-vol parameters. As intermediary results, we obtain high order expansions for at-the-money digital call option prices, which furthermore allow us to infer analogous results for the delta of at-the-money options. Simulation results indicate that our asymptotic expansions give good fits for options with maturities up to one month, underpinning their relevance in practical applications, and an analysis of the implied volatility skew in recent S&P 500 options data shows it to be consistent with the infinite variation jump component of our models.  相似文献   
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Most mortality models proposed in recent literature rely on the standard ARIMA framework (in particular: a random walk with drift) to project mortality rates. As a result the projections are highly sensitive to the calibration period. We therefore analyse the impact of allowing for multiple structural changes on a large collection of mortality models. We find that this may lead to more robust projections for the period effect but that there is only a limited effect on the ranking of the models based on backtesting criteria, since there is often not yet sufficient statistical evidence for structural changes. However, there are cases for which we do find improvements in estimates and we therefore conclude that one should not exclude on beforehand that structural changes may have occurred.  相似文献   
944.
In this paper, we focus on uncertainty issues on disabled lives survival probabilities of LTC insurance policyholders and its consequences on solvency capital requirement. Among the risks affecting long-term care portfolios, special attention is addressed to the table risk, i.e. the risk of unanticipated aggregate mortality, arising from the uncertainty in modeling LTC claimants survival law. The table risk can be thought as the risk of systematic deviations referring not only to a parameter risk but, as well, to any other sources leading to a misinterpretation of the life table resulting for example from an evolution of medical techniques or a change in rules of acceptance. In fine, the idea is to introduce the risk of systematic deviations arising from the uncertainty on the disabled lives death probabilities directly. We analyze the consequences of an error of appreciation on the disabled lives survival probabilities in terms of level of reserves and describe a framework in an Own Risk and Solvency Assessment perspective to measure the gap between the risk profile from the standard formula to the risk analysis specific to the organism.  相似文献   
945.
This cross-cultural study empirically investigates the cultural determinants of macro-level social and commercial entrepreneurship from a new institutional theory perspective. This study investigates if cultural shifts in cultural values, operationalized through the World Values Survey (WVS), impact the prevalence rates of social and commercial entrepreneurship at the national level. Social and commercial entrepreneurship rates are drawn from the 2009 Global Entrepreneurship Monitor (GEM) and aggregated for 53 countries in this cross-sectional analysis using multivariate regression. Findings indicate that traditional societal values positively impact commercial entrepreneurship prevalence rates, but negatively impact social entrepreneurship rates. Furthermore, self-expression societal values positively impact social entrepreneurship prevalence rates.  相似文献   
946.
We intend to further the research related to the factors that determine successful entrepreneurial endeavours by academic researchers, and thus put forth an exploratory model of Knowledge-Based Entrepreneurship (KBE). Given the lack of extant adequate indicators, a new scale was developed based on the most frequently cited constructs in the literature. A sample of 1,401 researchers from Portuguese universities was administered a questionnaire and the data collected permitted a validation with regards to the psychometric properties of the questionnaire, to see its applicability to the study. The findings suggest that the absence of a patenting history or start-up portfolio act as significant barriers to academic entrepreneurship. However, when the institutional strategy is to increase patenting and spin-off activities, the university should begin investing in creating a networking environment capable of reinforcing the researchers’ Social Capital. Observing the example of successful entrepreneurs motivates other researchers to consider the possibility of developing their own ventures. The Structural Equations Modelling (SEM) approach allowed for us to identify and measure the non-linear relationships that shape the core of KBE and influence the attainment of measurable outcomes aimed at encouraging entrepreneurship. A relatively high share of the variance of the dependent variables is explained by the model, ensuring their representativeness and contributing to the state-of-art of the knowledge in this research field.  相似文献   
947.
This article explains how the National Catholic Rural Life Conference (NCRLC), from its founding in 1923 to the present, applied basic Catholic principles in response to a succession of changes in American rural society. In doing so, it proposed a middle way between capitalism and socialism and between the Democratic and Republican parties. In the 1920s, the Reverend Edwin V. O'Hara founded the NCRLC mainly to bolster the demographically weak rural Church. In the 1930s, the NCRLC turned to economic concerns in response to the Great Depression. It supported many New Deal programs that helped farmers as well as cooperatives and a “back‐to‐the‐land” movement. The Conference consistently supported the family farm as the basic institution of a morally and economically sound rural society. In the 1940s and 1950s, the Conference entered the realm of international affairs under Monsignor Luigi G. Ligutti and addressed problems of world hunger, land reform, and underdeveloped countries. Under Monsignor Edward W. O'Rourke, who became director in 1960, the NCRLC joined in the movement for social justice and campaigned for the rights of the rural poor and migrant farm workers. Starting around 1970, the Conference became increasingly interested in environmental and energy issues. The NCRLC is in harmony with the 21st‐century pope, Francis, on rural and ecological issues.  相似文献   
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