1,721,032 research outputs found
On a Fair Value Model for Partecipating Life Insurance Policies
No full textThe aim of this paper is to analyze both the term structure of interest and mortality rates role for evaluating a fair value of a life insurance business. In particular, a fair value accounting impact on reserve evaluations is discussed comparing a traditional deterministic model based on local rules for an Italian balance sheet calculation and a stochastic one based on a diffusion process for both mortality and financial risks. As proposed by IAS Board we will separate the embedded derivatives from their host contracts, so the fair value of a traditional life insurance contract would be expressed as the value of four components: the basic contract, the participation option, the option to annuitise and the surrender option. A numerical application to a traditional Italian life insurance policy is discussed
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Longevity risk and financial market:some issues
No full textLongevity risk (LR) is undoubtedly a much discussed actuarial subject at international level;
it implicates uncertainty of mortality rates in the long term (i.e., unanticipated inter-temporal
variations) and the consequent effects on long term survival probabilities. Public and private
annuities providers (as pension funds and insurance companies) are involved in hedging the LR;
a classical decision procedure can be structured to solve an asset-liability mismatching problem,
introducing financial tools with payoff linked to longevity or mortality indexes
Environmental pollution from plasticiser compounds: Do we know enough about atmospheric levels and their contribution to human exposure in Europe?
No full textThe information available for the levels of plasticizers in urban air for the European region was reviewed. Wide variability in phthalates and BPA concentrations between differently urbanised areas emerged, due to the influence of vehicular traffic, waste management practices and presence of buildings, from which plasticizers are emitted. The ambient air levels measured have not shown a significant influence on human exposure, confirming that other pathways play a fundamental role. Anyway, given their toxicity, it would be important to intensify measurements campaigns, at least for DEHP and BPA, to monitor and improve air quality, and, finally, limit the health risks deriving from the exposure to a mixture of air toxic molecules
Nonlinear wave propagation in locally dissipative metamaterials via Hamiltonian perturbation approach
Full text linkThe cellular microstructure of periodic architected materials can be enriched by local intracellular mechanisms providing innovative distributed functionalities. Specifically, high-performing mechanical metamaterials can be realized by coupling the low-dissipative cellular microstructure with a periodic distribution of tunable damped oscillators, or resonators, vibrating at relatively high amplitudes. The benefit is the actual possibility of combining the design of wave-stopping bands with enhanced energy dissipation properties. This paper investigates the nonlinear dispersion properties of an archetypal mechanical metamaterial, represented by a one-dimensional lattice model characterized by a diatomic periodic cell. The intracellular interatomic interactions feature geometric and constitutive nonlinearities, which determine cubic coupling between the lattice and the resonators. The non-dissipative part of the coupling can be designed to exhibit a softening or a hardening behavior, by independently tuning the geometric and elastic stiffnesses. The nonlinear wavefrequencies and waveforms away from internal resonances are analytically determined by adopting a perturbation technique. The employed approach makes use of tools borrowed from Hamiltonian perturbation theory, together with techniques often used in the context of nearly-integrable Hamiltonian systems.The dispersion spectra are determined in closed, asymptotically approximate, form as a nonlinear function of the time-dependent decreasing amplitude decrement. The invariant manifolds defined by the harmonic periodic motions are also analytically determined. The asymptotic results are further validated numerically
- …
