Poverty measures and poverty orderings

We examine the conditions under which unanimous poverty rankings of income distributions can be obtained for a general class of poverty indices. The “per-capita income gap” and the Shorrocks and Thon poverty measures are particular members of this class. The conditions of dominance are stated in terms of comparisons of the corresponding TIP curves and areas.Peer Reviewe

Are circles isoperimetric in the plane with density er?

We prove that an isoperimetric region in R2 with density er must be convex and contain the origin, and provide numerical evidence that circles about the origin are isoperimetric, as predicted by the Log-Convex Density Conjecture

Stochastic comparisons of distorted variability measures

In this paper, we consider the dispersive order and the excess wealth order to compare the variability of distorted distributions. We know from Sordo (2009a) that the excess wealth order can be characterized in terms of a class of variability measures associated to the tail conditional distribution which includes, as a particular measure, the tail variance. Given that the tail conditional distribution is a particular distorted distribution, a natural question is whether this result can be extended to include other classes of variability measures associated to general distorted distributions. As we show in this paper, the answer is yes, by focussing on distorted distributions associated to concave distortion functions. For distorted distributions associated to more general distortions, the characterizations are stated in terms of the stronger dispersive order.Ministerio de Ciencia e Innovación (proyecto MTM2009-08326) y Consejería de Eonomía, Innovación y Ciencia (proyecto P09-SEJ-4739

On a property of Lorenz curves with monotone elasticity and its application to the study of inequality by using tax data

The Lorenz curve is the most widely used graphical tool for describing and comparing inequality of income distributions. In this paper, we show that the elasticity of this curve is an indicator of the effect, in terms of inequality, of a truncation of the income distribution. As an application, we consider tax returns as equivalent to the truncation from below of a hypothetical income distribution. Then, we replace this hypothetical distribution by the income distribution obtained from a general household survey and use the dual Lorenz curve to anticipate this effect.Peer Reviewe

Characterizations of classes of risk measures by dispersive orders

In this paper, a class C of risk measures, which generalizes the class of risk measures for the right-tail deviation suggested by Wang (1998), is characterized in terms of dispersive order. If dispersive order does not hold, unanimous comparisons are still possible by restricting our attention to a subclass of C and then the criterion is the excess wealth order. Sufficient conditions for stochastic equivalence of excess wealth ordered random variables are derived in terms of some particular measures of this subclass.Ministerio de Educación y Ciencia (grant SEJ2005-06678

Dispesion measures and dispersive orders

In this paper, the comparison of random variables according to the functionals of a general class of dispersion measures is characterized in terms of the dilation order. The Gini's mean difference is a particular member of this general class. In addition, a new and weaker order, called the second-order absolute Lorenz ordering, is introduced, and we judge random variables according to certain functionals of this class when the dilation order is not available

Carbon nanotubes gathered onto silica particles lose their biomimetic properties with the cytoskeleton becoming biocompatible

Carbon nanotubes (CNTs) are likely to transform the therapeutic and diagnostic fields in biomedicine during the coming years. However, the fragmented vision of their side effects and toxicity in humans has proscribed their use as nanomedicines. Most studies agree that biocompatibility depends on the state of aggregation/dispersion of CNTs under physiological conditions, but conclusions are confusing so far. This study designs an experimental setup to investigate the cytotoxic effect of individualized multiwalled CNTs compared to that of identical nanotubes assembled on submicrometric structures. Our results demonstrate how CNT cytotoxicity is directly dependent on the nanotube dispersion at a given dosage. When CNTs are gathered onto silica templates, they do not interfere with cell proliferation or survival becoming highly compatible. These results support the hypothesis that CNT cytotoxicity is due to the biomimetics of these nanomaterials with the intracellular nanofilaments. These findings provide major clues for the development of innocuous CNT-containing nanodevices and nanomedicines.Acknowledgments: This work was supported by the Spanish MINECO Project (references PI13/01074, PI16/00496 and CTM2014–58481-R, IDIVAL INNVAL15/15), Xunta de Galicia (Centro Singular de Investigación de Galicia-Accreditation 2016–2019 and EM2014/035), European Regional Development Fund – ERDF and Fundación Tatiana Pérez de Guzmán El Bueno

Characterization of stochastic orders by L-functionals

Random variables may be compared with respect to their location by comparing certain functionals ad hoc, such as the mean or median, or by means of stochastic ordering based directly on the properties of the corresponding distribution functions. These alternative approaches are brought together in this paper. We focus on the class of L-functionals discussed by Bickel and Lehmann (1975) and characterize the comparison of random variables in terms of these measures by means of several stochastic orders based on iterated integrals, including the increasing convex orde

The wide-field, multiplexed, spectroscopic facility WEAVE : survey design, overview, and simulated implementation

Funding for the WEAVE facility has been provided by UKRI STFC, the University of Oxford, NOVA, NWO, Instituto de Astrofísica de Canarias (IAC), the Isaac Newton Group partners (STFC, NWO, and Spain, led by the IAC), INAF, CNRS-INSU, the Observatoire de Paris, Région Île-de-France, CONCYT through INAOE, Konkoly Observatory (CSFK), Max-Planck-Institut für Astronomie (MPIA Heidelberg), Lund University, the Leibniz Institute for Astrophysics Potsdam (AIP), the Swedish Research Council, the European Commission, and the University of Pennsylvania.WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for the William Herschel Telescope, will see first light in late 2022. WEAVE comprises a new 2-degree field-of-view prime-focus corrector system, a nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and a single large IFU. These fibre systems feed a dual-beam spectrograph covering the wavelength range 366-959 nm at R ∼ 5000, or two shorter ranges at R ∼ 20,000. After summarising the design and implementation of WEAVE and its data systems, we present the organisation, science drivers and design of a five- to seven-year programme of eight individual surveys to: (i) study our Galaxy's origins by completing Gaia's phase-space information, providing metallicities to its limiting magnitude for ∼ 3 million stars and detailed abundances for ∼ 1.5 million brighter field and open-cluster stars; (ii) survey ∼ 0.4 million Galactic-plane OBA stars, young stellar objects and nearby gas to understand the evolution of young stars and their environments; (iii) perform an extensive spectral survey of white dwarfs; (iv) survey  ∼ 400 neutral-hydrogen-selected galaxies with the IFUs; (v) study properties and kinematics of stellar populations and ionised gas in z 1 million spectra of LOFAR-selected radio sources; (viii) trace structures using intergalactic/circumgalactic gas at z > 2. Finally, we describe the WEAVE Operational Rehearsals using the WEAVE Simulator.PostprintPeer reviewe