Search results for "Carter"
showing 10 items of 18 documents
Modelos y algoritmos de predicción fuzzy
2019
En un mundo tan globalizado la complejidad macro-económica, la volatilidad en los mercados y la estabilidad político-social de un país, afectan directamente a las cotizaciones de los valores bursátiles del país de referencia y añaden complejidad a la toma de decisiones. La riqueza de un análisis o inferencia sobre las cotizaciones de valores en mercados bursátiles tiene que servir como soporte para la toma de decisiones, por lo que no sólo han de basarse en una predicción puntual, de ahí radica la gran relevancia de las series temporales difusas. Ya que las series temporales difusas pueden tratar entornos donde hay incertidumbre en los datos (comportamientos o relaciones entre los datos) y/…
Smaller calcite lattice deformation caused by occluded organic material in coccoliths than in mollusk shell.
2015
7 pages; International audience; The growth and nucleation of biominerals are directed and affected by associated biological molecules. In this paper, we investigate the influence of occluded biomolecules on biogenic calcite from the coccolithophorid Pleurochrysis carterae and from chalk, a rock composed predominantly of fossil coccoliths. We compare the results with data on chalk from the extensively studied mussel Pinna nobilis that served as a control. Using high resolution synchrotron powder X-ray diffraction combined with in situ heating, the influence of organic compounds on the structure of the inorganic phase was probed. Two heating cycles allow us to differentiate the effects of th…
A naïve approach to speed up portfolio optimization problem using a multiobjective genetic algorithm
2012
a b s t r a c t Genetic algorithms (GAs) are appropriate when investors have the objective of obtaining mean-variance (VaR) efficient frontier as minimising VaR leads to non-convex and non-differential risk-return optimisation problems. However GAs are a time-consuming optimisation technique. In this paper, we propose to use a naive approach consisting of using samples split by quartile of risk to obtain complete efficient frontiers in a reasonable computation time. Our results show that using reduced problems which only consider a quartile of the assets allow us to explore the efficient frontier for a large range of risk values. In particular, the third quartile allows us to obtain efficie…
Do different models induce changes in mortality indicators? That is a key question for extending the Lee-Carter model
2021
[EN] The parametric model introduced by Lee and Carter in 1992 for modeling mortality rates in the USA was a seminal development in forecasting life expectancies and has been widely used since then. Different extensions of this model, using different hypotheses about the data, constraints on the parameters, and appropriate methods have led to improvements in the model's fit to historical data and the model's forecasting of the future. This paper's main objective is to evaluate if differences between models are reflected in different mortality indicators' forecasts. To this end, nine sets of indicator predictions were generated by crossing three models and three block-bootstrap samples with …
Modelling and forecasting mortality in Spain
2008
[EN] Experience shows that static life tables overestimate death probabilities. As a consequence of this overestimation the premiums for annuities, pensions and life insurance are not what they actually should be, with negative effects for insurance companies or policy-holders. The reason for this overestimation is that static life tables, through being computed for a specific period of time, cannot take into account the decreasing mortality trend over time. Dynamic life tables overcome this problem by incorporating the influence of the calendar when graduating mortality. Recent papers on the topic look for the development of new methods to deal with this dynamism. Most methods used in dyna…
La storia del gatto con gli stivali
2011
Durante años, los cuentos de hadas han sido contados por diferentes narradores sin necesidad de tener ningún derecho público. Diferentes narradores han contado a menudo historias similares sin problemas de plagios, y solo unos pocos han alcanzado el privilegio de firmar sus historias. La consecuencia de este hecho es que muchos de los cuentos de hadas son colecciones anónimas de tramas combinadas por la autoridad del género. Desde este punto de vista, los cuentos acaban siendo una especie de colección de coincidencias entre autores que defienden su derecho a contar “La verdadera historia” o “La historia de las historias”. Por lo tanto, podemos definir estos cuentos como un conjunto de auto…
DIO SALVI IL RESTAURO. L’apporto inglese alla cultura della conservazione dei monumenti
2020
Sebbene già riuscissimo a percepire quanto rilevante fosse l’apporto inglese per aver contribuito alla definizione del restauro modernamente inteso, sino ad oggi mancavano ancora sia una chiara visione d’insieme delle articolate vicende connesse all'affermazione dei princìpi conservativi, sia una più approfondita conoscenza delle fonti documentarie, necessarie al fine di tracciare i profili culturali dei protagonisti e scandagliarne i contributi teorici. La ricostruzione delle vicende è sviluppata entro margini temporali estesi all'incirca per tre secoli, dalla fine del Seicento al principio del Nove-cento, e strutturata attraverso la traduzione e lo studio di testi perlopiù mai circolati i…
Trasferimento energetico capacitivo e resistivo nella cervicoartrosi: nostra esperienza.
2009
Tecarterapia versus ionoforesi e ultrasuoni nel trattamento delle epicondiliti: approcci terapeutici a confronto
2010
Temporal evolution of some mortality indicators: Application to Spanish data
2012
[EN] In Spain, as in other developed countries, significant changes in mortality patterns have occurred during the 20th and 21st centuries. One reflection of these changes is life expectancy, which has improved in this period, although the robustness of this indicator prevents these changes from being of the same order as those for the probability of death. If, moreover, we bear in mind that life expectancy offers no information as to whether this improvement is the same for different age groups, it is important and necessary to turn to other mortality indicators whose past and future evolution in Spain we are going to study. These indicators are applied to Spanish mortality data for the pe…