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81.
Life insurance products are usually equipped with minimum guarantee and bonus provision options. The pricing of such claims is of vital importance for the insurance industry. Risk management, strategic asset allocation, and product design depend on the correct evaluation of the written options. Also regulators are interested in such issues since they have to be aware of the possible scenarios that the overall industry will face. Pricing techniques based on the Black & Scholes paradigm are often used, however, the hypotheses underneath this model are rarely met.To overcome Black & Scholes limitations, we develop a stochastic programming model to determine the fair price of the minimum guarantee and bonus provision options. We show that such a model covers the most relevant sources of incompleteness accounted in the financial and insurance literature. We provide extensive empirical analyses to highlight the effect of incompleteness on the fair value of the option, and show how the whole framework can be used as a valuable normative tool for insurance companies and regulators. 相似文献
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83.
Neuman NI Perec M González PJ Passeggi MC Rizzi AC Brondino CD 《The journal of physical chemistry. A》2010,114(50):13069-13075
We report powder and single crystal EPR measurements of [Cu(tda)(phen)](2)·H(2)tda (tda = thiodiacetate, phen = phenanthroline) at 9.7 GHz. This compound consists of centrosymmetric copper(II) ion dimers, weakly ferromagnetically exchange-coupled (J = +3.2 cm(-1)), in which the dimeric units are linked by hydrophobic chemical paths involving the phen molecules. EPR revealed that the triplet spectra are collapsed by interdimeric exchange interactions mediated by that chemical path. Analysis and simulation of the single crystal EPR spectra were performed using Anderson's exchange narrowing model, together with statistical arguments. This approach allowed us to interpret the spectra modulated by the interdimeric interactions in situations of weak, intermediate, and strong exchange. We evaluated an interdimeric exchange constant J' = 0.0070(3) cm(-1), indicating that hydrophobic paths can transmit weak exchange interactions between centers at relatively long distances of the order of ~10 ?. 相似文献
84.
Domenico Perrone 《Results in Mathematics》2014,66(1-2):213-225
In this paper, we show that if an integrable contact pseudo-metric manifold of dimension 2n + 1, n ≥ 2, has constant sectional curvature \({\kappa}\) , then the structure is Sasakian and \({\kappa=\varepsilon=g(\xi,\xi)}\) , where \({\xi}\) is the Reeb vector field. We note that the notion of contact pseudo-metric structure is equivalent to the notion of non-degenerate almost CR manifold, then an equivalent statement of this result holds in terms of CR geometry. Moreover, we study the pseudohermitian torsion \({\tau}\) of a non-degenerate almost CR manifold. 相似文献
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87.
For group III-nitrides with wurtzite structure the presence of fixed polarization interface charges yields new challenges in order to understand and control Schottky barrier heights, band offsets and 2D confinement in heterostructure FETs. In this short review experimental results obtained by in situ photoemission spectroscopy on MBE AlGaN/GaN heterostructures grown on 6H–SiC are discussed, with emphasis on the presence and interplay of surface electronic states. Schrödinger–Poisson calculations are performed to get the complete band scheme at the selected heterojunctions. Results on the polarity dependence of Pt/GaN Schottky barrier values from the literature are also discussed. 相似文献
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89.
Paola Benzi Elena Bottizzo Chiara Demaria Nicoletta Rizzi 《Journal of Chemical Sciences》2007,119(6):631-635
YBa2Cu3Ox (Y-123) and Bi2Sr2Ca1Cu2Ox (Bi-2212) films on various substrates have been prepared by Metal-Organic Deposition starting from different metallorganic
fluorine-free compounds and using a very simple instrumentation. The processing conditions include a rapid pyrolysis step
in air and an annealing step in oxygen for Y-123 and in air for Bi-2212. The films obtained have been characterized by X-ray
diffraction (XRD) and the formation of a superconducting phase of Y-123 or Bi-2212 was confirmed measuring the critical temperature
(T
c) with Ac-susceptibility and resistive measurements. Microstructure and final cationic ratios have been studied by scanning
electron microscopy (SEM) and energy dispersive spectroscopy (EDS). 相似文献
90.
There is now strong observational evidence that the expansion of the Universe is accelerating. The standard explanation invokes an unknown "dark energy" component. But such scenarios are faced with serious theoretical problems, which has led to increased interest in models where instead general relativity is modified in a way that leads to the observed accelerated expansion. The question then arises whether the two scenarios can be distinguished. Here we show that this may not be so easy, demonstrating explicitly that a generalized dark energy model can match the growth rate of the Dvali-Gabadadze-Porrati model and reproduce the 3+1 dimensional metric perturbations. Cosmological observations are then unable to distinguish the two cases. 相似文献