Partially linear models on Riemannian manifolds

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

A Note on the Estimation of the Hölder Constant

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

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

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

Certification Testing Approach for Propulsion System Design

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

Robust estimators in partly linear regression models on Riemannian manifolds

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

Locally adaptive density estimation on Riemannian manifolds

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

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

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

X-37 Storable Propulsion System Design and Operations

In a response to NASA's X-37 TA-10 Cycle-1 contract, Boeing assessed nitrogen tetroxide (N2O4) and monomethyl hydrazine (MMH) Storable Propellant Propulsion Systems to select a low risk X-37 propulsion development approach. Space Shuttle lessons learned, planetary spacecraft, and Boeing Satellite HS-601 systems were reviewed to arrive at a low risk and reliable storable propulsion system. This paper describes the requirements, trade studies, design solutions, flight and ground operational issues which drove X-37 toward the selection of a storable propulsion system. The design of storable propulsion systems offers the leveraging of hardware experience that can accelerate progress toward critical design. It also involves the experience gained from launching systems using MMH and N2O4 propellants. Leveraging of previously flight-qualified hardware may offer economic benefits and may reduce risk in cost and schedule. This paper summarizes recommendations based on experience gained from Space Shuttle and similar propulsion systems utilizing MMH and N2O4 propellants. System design insights gained from flying storable propulsion are presented and addressed in the context of the design approach of the X-37 propulsion system