METAPHOR: Probability density estimation for machine learning based photometric redshifts

We present METAPHOR (Machine-learning Estimation Tool for Accurate PHOtometric Redshifts), a method able to provide a reliable PDF for photometric galaxy redshifts estimated through empirical techniques. METAPHOR is a modular workflow, mainly based on the MLPQNA neural network as internal engine to derive photometric galaxy redshifts, but giving the possibility to easily replace MLPQNA with any other method to predict photo-z's and their PDF. We present here the results about a validation test of the workflow on the galaxies from SDSS-DR9, showing also the universality of the method by replacing MLPQNA with KNN and Random Forest models. The validation test include also a comparison with the PDF's derived from a traditional SED template fitting method (Le Phare).Comment: proceedings of the International Astronomical Union, IAU-325 symposium, Cambridge University pres

Probability density estimation of photometric redshifts based on machine learning

Photometric redshifts (photo-z's) provide an alternative way to estimate the distances of large samples of galaxies and are therefore crucial to a large variety of cosmological problems. Among the various methods proposed over the years, supervised machine learning (ML) methods capable to interpolate the knowledge gained by means of spectroscopical data have proven to be very effective. METAPHOR (Machine-learning Estimation Tool for Accurate PHOtometric Redshifts) is a novel method designed to provide a reliable PDF (Probability density Function) of the error distribution of photometric redshifts predicted by ML methods. The method is implemented as a modular workflow, whose internal engine for photo-z estimation makes use of the MLPQNA neural network (Multi Layer Perceptron with Quasi Newton learning rule), with the possibility to easily replace the specific machine learning model chosen to predict photo-z's. After a short description of the software, we present a summary of results on public galaxy data (Sloan Digital Sky Survey - Data Release 9) and a comparison with a completely different method based on Spectral Energy Distribution (SED) template fitting.Comment: 2016 IEEE Symposium Series on Computational Intelligence, SSCI 2016 784995

When Merit Breeds Luck (or Not): An Experimental Study on Distributive Justice

We experimentally investigate subjects’ preferences for redistribution depending on i) their personal stake in the outcome (either absent or not), ii) the effect of luck in strengthening or weakening the income inequality as derived from merit, and iii) whether individuals are informed about their relative wealth position in the society or not. We find that self-interest is the main driver of subjects’ redistributive choices when they have direct monetary interests in the outcome. Leaving subjects under the veil of ignorance about their relative gross income position reduces selfish behavior, also controlling for beliefs and risk attitude. Inequality aversion and fairness mostly affect redistributive choices of impartial spectators when recipients of redistribution are not informed about their initial endowments, suggesting that the luck vs. merit effect is not the only driver of redistribution on behalf of others

Critical issues in the relationships between patient relatives and hospital staff: qualitative research based on focus group

In Italy the number of elderly patients is increasing and often a family member, also called primary caregiver (CG), assists them. The aim of this study is to describe the peculiar relationships between the family primary CG and the hospital staff, when an elderly patient is admitted to hospital, to demonstrate how this may affect his/her clinical management during the hospital stay and formulate new research projects and organizational rearrangements

Realtà aumentata per favorire un apprendimento inclusivo

Nel presente lavoro, dopo aver illustrato da un punto di vista teorico la Realtà Aumentata e le sue principali caratteristiche, si analizzano le potenzialità di quest’ultima. Scopo del presente studio è infatti quello di conoscere gli impatti della realtà aumentata sull’apprendimento, sulla motivazione e, più specificamente studiarne i possibili effetti in ambito scolastico secondo una logica inclusiva.In the present work, after having illustrated the Augmented Reality and its main characteristics from a theoretical point of view, the potential of the latter is analyzed. The purpose of the present study is in fact to know the impacts of augmented reality on learning, on motivation and, more specifically, to study its possible effects in the scholastic context according to an inclusive logic

Augmented reality to promote inclusive learning

In the present work, after having illustrated the Augmented Reality and its main characteristics from a theoretical point of view, the potential of the latter is analyzed. The purpose of the present study is in fact to know the impacts of augmented reality on learning, on motivation and, more specifically, to study its possible effects in the scholastic context according to an inclusive logic. Realtà aumentata per favorire un apprendimento inclusivoNel presente lavoro, dopo aver illustrato da un punto di vista teorico la Realtà Aumentata e le sue principali caratteristiche, si analizzano le potenzialità di quest’ultima. Scopo del presente studio è infatti quello di conoscere gli impatti della realtà aumentata sull’apprendimento, sulla motivazione e, più specificamente studiarne i possibili effetti in ambito scolastico secondo una logica inclusiva

Layered double hydroxides with low Al content and new intercalate structures

Layered double hydroxides (LDHs) containing Mg2+ and Al3+ as divalent and trivalent cations, respectively, have been synthesized by a procedure based on hydrolysis of a mixture of metal alcoholates, and have been characterized mainly by Wide Angle X-ray diffraction (WAXD) and Fourier Transform Infrared (FTIR) measurements. The used procedure is suitable to prepare LDHs with Al molar fractions, x(Al)=Al/(Al+Mg), as low as 0.1. The same LDH preparation procedure, for x(Al)<0.1, produces thermally stable intercalates with alkoxy anions, exhibiting layers similar to those of brucite, which maintain a high degree of order only in the hexagonal packing of the hydroxide groups. In particular, the basal periodicity increases from nearly 0.8 nm up to nearly 1.3 nm, due to the parallel staking of hexanolate groups in the clay galleries. (C) 2012 Elsevier B.V. All rights reserved