Nonparametric estimation in models with Lévy type jumps and stochastic volatility

We introduce a nonparametric estimator of the volatility function in univariate processes with Lévy type jumps and stochastic volatility when we observe the state variable at discrete times. Our results rely on the fact that it is possible to recognize the discontinuous part of the state variable from those squared increments between observations exceeding a suitable threshold. We discuss the implementation of the estimator with high-frequency data

Spin-Particles Entanglement in Robertson-Walker Spacetime

We study the entanglement between two modes of Dirac field in an expanding spacetime characterized by the Robertson-Walker metric. This spacetime model turns out to be asymptotically (in the remote past and far future regions) Minkowskian. Then, on the one hand we show entanglement creation between particles and anti-particles when passing from remote past to far future. On the other hand we show that particles entanglement in the remote past degrades into the far future. These effects are traced back to particles creation. In our analysis we highlight the role of spin (polarization) of particles and compare the results with those obtainable without accounting for it

Preserving Information from the Beginning to the End of time in a Robertson-Walker Spacetime

Preserving information stored in a physical system subjected to noise can be modeled in a communication-theoretic paradigm, in which storage and retrieval correspond to an input encoding and output decoding, respectively. The encoding and decoding are then constructed in such a way as to protect against the action of a given noisy quantum channel. This paper considers the situation in which the noise is not due to technological imperfections, but rather to the physical laws governing the evolution of the universe. In particular, we consider the dynamics of quantum systems under a 1+1 Robertson-Walker spacetime and find that the noise imparted to them is equivalent to the well known amplitude damping channel. Since one might be interested in preserving both classical and quantum information in such a scenario, we study trade-off coding strategies and determine a region of achievable rates for the preservation of both kinds of information. For applications beyond the physical setting studied here, we also determine a trade-off between achievable rates of classical and quantum information preservation when entanglement assistance is available.Comment: 19 pages, 3 figures. Presentation updated, matches the published versio

Riemannian-geometric entropy for measuring network complexity

A central issue of the science of complex systems is the quantitative characterization of complexity. In the present work we address this issue by resorting to information geometry. Actually we propose a constructive way to associate to a - in principle any - network a differentiable object (a Riemannian manifold) whose volume is used to define an entropy. The effectiveness of the latter to measure networks complexity is successfully proved through its capability of detecting a classical phase transition occurring in both random graphs and scale--free networks, as well as of characterizing small Exponential random graphs, Configuration Models and real networks.Comment: 15 pages, 3 figure

A geometric entropy detecting the Erd\"os-R\'enyi phase transition

We propose a method to associate a differentiable Riemannian manifold to a generic many degrees of freedom discrete system which is not described by a Hamiltonian function. Then, in analogy with classical Statistical Mechanics, we introduce an entropy as the logarithm of the volume of the manifold. The geometric entropy so defined is able to detect a paradigmatic phase transition occurring in random graphs theory: the appearance of the `giant component' according to the Erd\"os-R\'enyi theorem.Comment: 11 pages, 3 figures. arXiv admin note: substantial text overlap with arXiv:1410.545

Embedding Words and Senses Together via Joint Knowledge-Enhanced Training

Word embeddings are widely used in Nat-ural Language Processing, mainly due totheir success in capturing semantic infor-mation from massive corpora. However,their creation process does not allow thedifferent meanings of a word to be auto-matically separated, as it conflates theminto a single vector. We address this issueby proposing a new model which learnsword and sense embeddings jointly. Ourmodel exploits large corpora and knowl-edge from semantic networks in order toproduce a unified vector space of wordand sense embeddings. We evaluate themain features of our approach both qual-itatively and quantitatively in a variety oftasks, highlighting the advantages of theproposed method in comparison to state-of-the-art word- and sense-based models

Giorno della Memoria 2016. Memoria della Shoah e responsabilit\ue0 presente-Progetto di Terza Missione

In linea con le finalit\ue0 intese dalla Presidenza del Consiglio Regionale delle Marche nel farsi promotrice e coordinatrice delle iniziative organizzate sul territorio regionale per la celebrazione del Giorno della Memoria 2016, e in accordo con il tema \u201cLa memoria contro ogni discriminazione\u201d proposto dalla Presidenza stessa agli Enti collaboratori (la Comunit\ue0 ebraica di Ancona, l\u2019Ufficio scolastico regionale, l\u2019Istituto di Storia Marche, la Rete Universitaria per il Giorno della Memoria, l\u2019Anci Marche), l\u2019evento "Memoria della Shoah e responsabilit\ue0 presente" organizzato dall\u2019Universit\ue0 di Macerata per il giorno 29 gennaio 2016 \u2012 articolato in Convegno, Mostra e Spettacolo \u2012 \ue8 mirato a dare un degno risalto al valore della Memoria e dell\u2019educazione dei cittadini, soprattutto dei giovani, al rifiuto di ogni forma di sopruso e di discriminazione nei confronti di ogni popolo, cultura, etnia e religione, nella ferma convinzione che \ue8 primariamente attraverso la trasmissione del sapere, della conoscenza e di valori positivi, da un lato, e lo sviluppo di una cultura del pluralismo e di un sentimento sempre pi\uf9 diffuso di cura, attenzione e tutela dei diritti umani e civili, dall\u2019altro, che viene resa possibile la costruzione di una civilt\ue0 fondata sulla pacifica convivenza fra popoli e, al contempo, lo scardinamento di mentalit\ue0 razziste, antisemite e negazioniste

Dysfunctional eating behaviours, anxiety and depression in Italian boys and girls: the role of mass media

Objective: Extensive research has implicated identification with characters in mass media in the emergence of disordered eating behavior in adolescents. We explored the possible influence of the models offered by television (TV) on adolescents’ body image, body uneasiness, eating-disordered behavior, depression, and anxiety. Methods: Three hundred and one adolescents (aged 14-19) from southern Italy participated. They completed a questionnaire on media exposure and body dissatisfaction, the Eating Disorder Inventory-2, the Body Uneasiness Test, the Beck Depression Inventory, and the State-Trait Anxiety Inventory – Form Y. Results: The main factors contributing to females’ eating-disordered behaviors were their own desires to be similar to TV characters, the amount of reality and entertainment TV they watched, and the discrepancy between their perceptions of their bodies and those of TV characters. Friends’ desire to be similar to TV characters contributed most to depression, anxiety, body uneasiness, and eating disorders for both males and females. Conclusion: Our data confirm that extensive watching of reality and entertainment TV correlates with eating-disordered behavior among females. Moreover, the well-known negative effects of the media on adolescents’ eating-disordered behaviors may also be indirectly transmitted by friends who share identification with TV characters

A new exotic fish for the Mediterranean Sea: Chaetodon auriga Forsskål, 1775 (Perciformes: Chaetodontidae)

The presence of Chaetodon auriga Forsskål, 1775 is reported for the first time from the Mediterranean Sea. A specimen was spearfished in 2015 in the central Mediterranean Sea and was in all likelihood an aquarium release. This and similar cases are discussed, with particular emphasis on exotic fishes notoriously known to be commonly kept in aquarium