1,721,050 research outputs found
Mortality neural forecasting
Get PDFPredicting mortality is a major challenge for both demographers and actuaries. The latter need to anticipate various future mortality scenarios with the greatest possible accuracy, as in the case of annuities pricing and longevity risk assessments. However, the current wide range of stochastic mortality models highlights some deficiencies in predicting future mortality realizations, particularly when accelerations or decelerations of longevity occur. The aim of this research thesis is to investigate the adequacy of a new mortality forecasting approach based on artificial Neural Networks. To this end, after an examination of the theoretical Neural Networks fundamentals, the present work shows the Neural Networks competitiveness in predicting the future dynamics of human mortality, also allowing the efficacy of already existing predictive models, such as the canonical Lee-Carter model. Therefore, our data-driven proposal contributes to the mortality literature as new advance in mortality forecasting, that is the neural forecasting approach
La decisione ottima nel contratto riassicurativo
No full textNel presente lavoro gli autori, mediante la Teoria delle decisioni, considerano il problema di scelta che si presenta ad una impresa assicuratrice nel decidere se ricorrere o meno alla stipulazione di un contratto riassicurativo. In primo luogo viene impostato il generico problema decisionale in un contesto di incertezza e la relativa strategia ottimale di risoluzione; in secondo luogo viene proposto un modello stocastico discreto, comprensivo di esemplificazione numerica, in grado di supportare la decisione riassicurativa dell’assicuratore cedente, mantenendo conformità e coerenza con la teoria espost
A dynamic game approach for optimal consumption, investment and life insurance problem
Get PDFIn this paper, we consider a multi-agent portfolio optimization model with life insurance for two players with random lifetime under a dynamic game approach. Each player is a price-taker and invests in the market to maximize her own utility for consumption and bequest. The market is complete and consists of n different assets, of which n−1 are risky with prices driven by Geometric Brownian motion, while one is risk-free. We analyze both the non-cooperative and cooperative scenarios, and by considering the family of CRRA utility functions, we determine the closed-form expressions of the optimal consumption, investment, and life insurance for both players. A sensitivity analysis is provided both to illustrate the impact of the biometric and risk aversion parameters on the optimal controls and to compare the non-cooperative strategies with the cooperative ones. As a result, we suggest that cooperation favors the consumption optimality, while non-cooperation promotes the coverage of the risk of death
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Designing amortization plans by fairness
Get PDFAmortization plans are well-known financial operations to repay interest-bearing loans through a sequence of periodic payments. Since amortization plans are generally settled according to the compound interest law, some questions arise about the supposed presence of anatocism and the consequent legal matters. In this paper, we derive the traditional amortization plans by means of an alternative approach, based on the concept of fair amortization and without assuming a financial law. We find that the traditional amortization plan with constant installments can be derived in this way and the supposed presence of anatocism is excluded. An investigation on the possible anatocism, in case of delayed payment of interest, completes the discussion
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