12,052 research outputs found

    Partially linear models on Riemannian manifolds

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    In partially linear models the dependence of the response y on (x^T,t) is modeled through the relationship y=\x^T \beta+g(t)+\epsilon where \epsilon is independent of (x^T,t). In this paper, estimators of \beta and g are constructed when the explanatory variables t take values on a Riemannian manifold. Our proposal combine the flexibility of these models with the complex structure of a set of explanatory variables. We prove that the resulting estimator of \beta is asymptotically normal under the suitable conditions. Through a simulation study, we explored the performance of the estimators. Finally, we applied the studied model to an example based on real dataset.Comment: 7 pages, 2 figure

    Income distribution in the Latin American Southern Cone during the first globalization boom, ca: 1870-1920

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    Latin America is the most unequal region in the world and there is a lively debate concerning the explanations and timing of such high levels of income inequality. Latin America was also the region, not including European Offshoots, which experienced the most rapid growth during the first globalization boom. It can, therefore, be taken as an interesting case study for how globalization forces impinged on growth and income distribution in peripheral regions. This paper presents a first estimate of income inequality in the Southern Cone of South America (Brazil 1872 and 1920, Chile 1870 and 1920, Uruguay 1920) and some assumptions concerning Argentina (1870 and 1920), and Uruguay (1870). We find an increasing inequality trend between 1870 and 1920 which can be explained as a process of inequality both within individual countries and between countries. This trend is discussed along three lines: the relation between inequality and per capita income levels; the dynamics of the expansion to new areas, and movements of relative factor prices and of the terms of trade.Globalization, Growth, Income inequality, Latin American Southern Cone, Regional inequality, Terms of trade

    Locally adaptive density estimation on Riemannian manifolds

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    In this paper, we consider kernel type estimator with variable bandwidth when the random variables belong in a Riemannian manifolds. We study asymptotic properties such as the consistency and the asymptotic distribution. A simulation study is also considered to evaluate the performance of the proposal. Finally, to illustrate the potential applications of the proposed estimator, we analyse two real examples where two different manifolds are considered

    A Note on the Estimation of the Hölder Constant

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    In this article, we develop a nonparametric estimator for the Hölder constant of a density function. We consider a simulation study to evaluate the performance of the proposal and construct smooth bootstrap confidence intervals. Also, we give a brief review over the impossibility to decide whether a density function is Hölder.Fil: Henry, Guillermo Sebastian. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rodriguez, Daniela Andrea. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sued, Raquel Mariela. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Inversión,Crecimiento y Desarrollo de la Economía Nicaragüense: La Inversión Privada en las Construcciones Verticales y su Incidencia en la Disminución del Desempleo 2009-2015

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    El tema principal sobre “inversión, crecimiento y desarrollo”, en el estudio abarca al sector construcción como una herramienta para medir el flujo de las inversiones privadas, y predecir inversiones futuras en el sector, para toma de decisiones de política económica

    Robust estimators in partly linear regression models on Riemannian manifolds

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    Under a partly linear model we study a family of robust estimates for the regression parameter and the regression function when some of the predictors take values on a Riemannian manifold. We obtain the consistency and the asymptotic normality of the proposed estimators. Simulations and an application to a real dataset show the good performance of our proposal under small samples and contamination.Fil: Henry, Guillermo Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santalo". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santalo"; ArgentinaFil: Rodriguez, Daniela Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigaciones Matemáticas "Luis A. Santalo". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Matemáticas "Luis A. Santalo"; Argentin

    Certification Testing Approach for Propulsion System Design

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    The Certification of Propulsion Systems is costly and complex which involves development and qualification testing. The desire of the certification process is to assure all requirements can be demonstrated to be compliant. The purpose of this paper is to address the technical design concerns of certifying a system for flight. The authors of this paper have experience the lessons learned from supporting the Shuttle Program for Main Propulsion and On Orbit Propulsions Systems. They have collaborated design concerns for certifying propulsion systems. Presented are Pressurization, Tankage, Feed System and Combustion Instability concerns. Propulsion System Engineers are challenged with the dilemma for testing new systems to specific levels to reduce risk yet maintain budgetary targets. A methodical approach is presented to define the types of test suitable to address the technical issues for qualifying systems for retiring the risk levels

    The Solar Neighborhood. XXVI. AP Col: The Closest (8.4 pc) Pre-Main-Sequence Star

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    We present the results of a multi-technique investigation of the M4.5Ve flare star AP Col, which we discover to be the nearest pre-main-sequence star. These include astrometric data from the CTIO 0.9m, from which we derive a proper motion of 342.0+/-0.5 mas yr^-1, a trigonometric parallax of 119.21+/-0.98 mas (8.39+/-0.07 pc), and photometry and photometric variability at optical wavelengths. We also provide spectroscopic data, including radial velocity (22.4+/-0.3 km s^-1), lithium Equivalent Width (EW) (0.28+/-0.02 A), H-alpha EW (-6.0 to -35 A), {\it vsini} (11+/-1 km s^-1), and gravity indicators from the Siding Spring 2.3-m WiFeS, Lick 3-m Hamilton echelle, and Keck-I HIRES echelle spectrographs. The combined observations demonstrate that AP Col is the closer of only two known systems within 10 pc of the Sun younger than 100 Myr. Given its space motion and apparent age of 12-50 Myr, AP Col is likely a member of the recently proposed ~40 Myr old Argus/IC 2391 association.Comment: 31 pages, 11 figure
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