2,211 research outputs found
The additive model with different smoothness for the components
We consider an additive regression model consisting of two components
and , where the first component is in some sense "smoother" than the
second . Smoothness is here described in terms of a semi-norm on the class
of regression functions. We use a penalized least squares estimator of and show that the rate of convergence for is
faster than the rate of convergence for . In fact, both rates are
generally as fast as in the case where one of the two components is known. The
theory is illustrated by a simulation study. Our proofs rely on recent results
from empirical process theory.Comment: 26 pages, 4 figure
Education for Rural People: A Neglected Key To Food Security
In the world there are approximately 800 million people who live in condition of food insecurity and illiteracy. This paper shows that education is a key to food security for rural populations in developing countries. Attention is drawn to rural areas because they are traditionally more disadvantaged by national educational policies. The theoretical foundation of this research is that being educated improves rural people’s capacity to diversify assets and activities, increase productivity and income, foster resilience and competitiveness, access information on health and sanitation, strengthen social cohesion and participation: these are all essential elements to ensure food security in the long run. The main findings of this research are the following: first, the association between food insecurity and primary education is very high, while it decreases progressively with basic, secondary, and tertiary education. Such a two-way relationship is expressed through graphical tools and correlation coefficients. Second, the econometric model shows that primary education is a crucial element to reduce food insecurity in rural areas, even when compared to other factors such as access to water, health, and sanitation. Concluding from this model, an increase of access to primary education by 100% causes a decrease of food insecurity by approximately 20% or 24% depending on the definition of food insecurity and its measurement. Finally, since in most of developing countries the majority of people live in rural areas, and since it is in these areas that the largest proportion of world poverty and hunger exists, we can conclude that education for rural people is a relevant tool for promoting overall national food security.Education, Food Security, Human Development, Cross-
Geomorphology and sedimentology of Porto Pino, SW Sardinia, Western Mediterranean
This paper presents a detailed (1:4000) geomorphological, sedimentological and ecological map of a Mediterranean microtidal wave-dominated beach system and adjacent inner shelf. This map is an innovative cartographic product that integrates a range of processes of present and past timeframes. It is part of a larger cartography on the coastal geomorphology of Sardinia (Italy) aiming to facilitate coastal management practices and future scientific research. The study area is located in SW Sardinia (Italy), and focuses on Porto Pino beach, an important tourist destination of semi-pristine nature, facing environmental pressures common to many coastal Mediterranean settings. In this context, the main human impact on coastal dune habitats is described and a full environmental characterization of the beach system is presented
From food availability to nutritional capabilities: Advancing food security analysis
AbstractThis paper has a threefold objective. First, it provides a comprehensive review of different approaches to analysing food security. Second, it highlights the added value provided by the capability approach and the human development paradigm. Third, it proposes a methodology to assess food security through this approach. Our proposal entails three basic steps: (1) analysis of food entitlements; (2) analysis of nutritional capabilities and (3) analysis of the capability to be food secure. In this way, we can move beyond income, entitlement or livelihood related frameworks, and identify the root causes of food insecurity. Food insecurity can be the result of a lack of education, health or other basic capabilities that constitute people's wellbeing. This, therefore, allows situating the study within the broader area of wellbeing and development
Dual Farrell measures of efficiency
This paper is a revised version of an old 1982 paper by the author, partially published in Spanish as Muro and Vera (1983) and cited for example in Fare (1985). The usual disclaimer appliesThis paper provides several definitions of efficiency measures in the price space. Economic and scale aspects of inefficiency are considered to give empirical content to the measurement of efficiency when the production technology is described by cost functions models. It shows, in the Hanoch’s symmetric duality approach, how the new definitions preserve the ranking of efficiency, are formally dually symmetric to the ones defined in the input space, and both are established with respect to different descriptions of the same technology. In addition, graphical procedures are utilized to make an insight into the achievement of polar technologies from primal ones and into the relationship between Shephard’s lemma and Roy’s identity
Study of cloud activity at the "Storm-Alley" region on Saturn
The objective of this thesis is to obtain experimental energy spectra for potential vorticity of the storms and clouds in the "Storm Alley" region in Saturn by using images taken by Cassini’s ISS instrument. The brightness signals of the clouds will be extracted by using planetary images navigation and signal processing in order to delete the limb darkening of the planet. The obtained signals will be denoised by using different methods such as a Moving Average Filter and a Constrained Deconvolution Filter. The experimental energy spectra will be obtained by computing a FFT of the experimental brightness signals. Finally, computing the fit line for the experimental energy spectra and the spectra obtained by simulations developed in the past using the Shallow-Water equations, both spectra will be compared to see if the simulations are correct and can be verified. To have a better understanding of the process carried out in this thesis, concepts of the Cassini mission, the "Storm Alley" region, the Shallow-Water method, planetary turbulence, planetary photometry, planetary image navigation, energy spectra and denoising filters will be providen
Cine-forum: “La felicidad en el séptimo arte"
ComunicaciĂłn presentada en el Curso "La felicidad humana", dentro de los Cursos de verano UBU 201
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