Threshold stochastic unit root models

This paper introduces a new class of stochastic unit root (STUR) processes, where the randomness of the autorregresive unit root is driven by a threshold variable. These new models, the threshold autorregresive stochastic unit root (TARSUR) models, are stationary in some regimes and mildly explosive in others. TARSUR models are not only an alternative to fixed unit root models but present interpretation, estimation and testing advantages with respect to the existent STUR models. The paper analyzes the stationarity properties of the TARSUR models and proposes a simple t -statistic for testing the null hypothesis of a fixed unit root versus a stochastic unit root hypothesis. It is shown that its asymptotic distribution (AD) depends on the knowledge we have about the threshold values: known, unknown but identified, and unknown and unidentified. In the first two cases the AD is a standard Normal distribution, while in the last one the AD is a functional of Brownian Motions and Brownian Sheets. Monte Carlo simulations show that the proposed tests behave very well in finite samples and that the Dickey-Fuller test cannot easily distinguish between an exact unit root and a threshold stochastic unit root. The paper concludes with applications to stock prices and interest rates where the hypothesis of a fixed unit root is rejected in favor of the threshold stochastic unit root

Upper and lower estimates in Banach sequence spaces

summary:Here we study the existence of lower and upper $\ell _p$-estimates of sequences in some Banach sequence spaces. We also compute the sharp $\ell _p$ estimates in their basis. Finally, we give some applications to weak sequential continuity of polynomials

La representación de los políticos en revistas femeninas de alta gama: Un estudio de caso.

The increasing speculation that the policy has experienced in the evolution of its relationship with media and citizens has become a major source of content for mass media that intends to provide informative products blended with entertainment. About this dominant trend known as "infotainment", most research is linked to the advancement of television, which has generated a false feeling of emptiness on the existence of “soft news” about politicians (and specifically about women politicians), in printed media. Given the lack of scientific background to explain the presence of the phenomenon beyond the television market, this study analyzes the representation of male and female leaders in highend women's magazines (RFAG) 'Glamour', 'Telva', 'Woman' , 'Elle' and 'Vogue', through interviews published in 2011 on the occasion of the elections to the Spanish Parliament. From a comparative and gender perspective, the objective of this analysis seeks to highlight the proliferation of a particular format: the “soft interview”, composed of personal questions alternated with professional questions, with a greater role of the first option when the gender of the interviewee is femaleLa creciente espectacularización que ha experimentado la política en la evolución de su relación con medios y ciudadanos se ha convertido en una de las principales fuentes de contenido para los mass media que persiguen ofrecer al público productos informativos mezclados con entretenimiento. Sobre esta preponderante tendencia conocida como “infotainment”, el grueso de investigaciones publicadas aparece ligado al avance de la televisión, lo que ha generado una falsa impresión de vacío sobre la existencia de “noticias blandas” protagonizadas por políticos (y más concretamente por políticas), en medios impresos. Ante la falta de antecedentes científicos que expliquen la presencia del fenómeno más allá del mercado televisivo, este estudio analiza la representación de los líderes y lideresas en las revistas femeninas de alta gama (RFAG) ‘Glamour’, ‘Telva’, ‘Woman’, ‘Elle’ y ‘Vogue’, a través de las entrevistas publicadas en el año 2011 con motivo de las elecciones a Cortes Generales en España. Desde una perspectiva comparativa y de género, el objetivo del análisis radica en evidenciar la proliferación de un particular formato: el de la “soft interview” o “entrevista blanda”, integrado por cuestionarios que alternan las preguntas personales con preguntas profesionales, con un mayor protagonismo de las primeras cuando el entrevistado es muje

Compact polynomials between Banach spaces

Depto. de Análisis Matemático y Matemática AplicadaFac. de Ciencias MatemáticasTRUEDGYCITpu

The seminar of nuclear safety in advanced reactors and the seminar of nuclear fusion: two formative initiatives from Universidad Politécnica de Madrid and spanish young Generation in Nuclear (Jóvenes Nucleares)

panish Young Generation in Nuclear (Jóvenes Nucleares) is a commission of the Spanish Nuclear Society (SNE), whose main goals are to spread knowledge about nuclear energy among the society. Following this motivation, two Seminars have been carried out with the collaboration of the Technical University of Madrid: The Seminar of Nuclear Safety in Advanced Reactors (SRA) and the Seminar of Nuclear Fusion (SFN). The first one, which has been celebrated every year since 2010, aims to show clearly the advances that have been obtained in the section of safety with the new reactors, from a technical but simple point of view and without needing great previous nuclear engineering knowledge. The second one, which first edition was held in 2011, aims to give a general overview of the past, present and future situation of nuclear fusion technology, and was born as a result of the increasing interest of our Spanish Young Generation members in this technology

Celsius Bloodhound

The Library Linkage Project (PrEBi) has as main objective to share the bibliographic acervus resident in ISTEC Institutions, in order to satisfy the demand of Researchers, Teachers and Students. To manage the bibliography requirements (journal articles, book chapters, congress proceedings, theses and patents) made by users, it's been developed the Celsius Software. Nowadays the main job of Celsius administrators is to lookup requests in ISTEC and non-ISTEC Institutions' catalogs by hand which takes many hours to check all until the resource is found. In order to perform this task more efficiently, it has been created in PrEBi the Celsius Bloodhound Project. This project, currently in analysis and design stage, intends to automatize this tedious job by searching and fetching records from library servers. Bloodhound's design is flexible enough to allow connections from almost any application and to connect to many different remote catalogues. Bloodhound will be able to interact transparently with many servers, taking advance of existing technologies and protocols, improving quality service in the search of resources in PrEBi and other Institutions as well

Revisão de diferentes implementações para a preservação digital: para uma proposta metodológica de preservação e auditoria de confiança de RI

This work introduces the initial experience of an infrastructure for digital documents preservation in archives or repositories. Prior backgrounds of similar infraestructures are recognized in this work, and among them three successful experiences are described. These experiences are all aimed to connect a digital repository with different software tools able to ensure digital preservation of repository contents according to OAIS ISO 14721 standard (2012). After the description of the three models, we describe a prototype under development in the repositories supported by PREBI-SEDICI (UNLP), which uses the software tools DSpace, Archivematica and ArchivesSpace. In this prototype, DSpace handles the ingest and delivery of digital contents, while Archivematica performs all the required digital preservation activities. This is achieved through a set of microservices applied to a conceptual structure similar to the information package (IP) in its differents versions (SIP, AIP, DIP). The resulting structure of the IP includes checksums, original files, logs, transfer documentation and XML metadata. The main purpose of this work is to show the background activities already carried out in institutions around the world, and to start a research project aiming to generate ideas and thoughts in the Latin American context

Revisão de diferentes implementações para a preservação digital: para uma proposta metodológica de preservação e auditoria de confiança de RI

This work introduces the initial experience of an infrastructure for digital documents preservation in archives or repositories. Prior backgrounds of similar infrastructures are recognized in this work, and among them three successful experiences are described. These experiences are all aimed to connect a digital repository with different software tools able to ensure digital preservation of repository contents according to OAIS ISO 14721 standard (2012). After the description of the three models, we describe a prototype under development in the repositories supported by PREBI-SEDICI (UNLP), which uses the software tools DSpace, Archivematica and ArchivesSpace. In this prototype, DSpace handles the ingest and delivery of digital contents, while Archivematica performs all the required digital preservation activities. This is achieved through a set of microservices applied to a conceptual structure similar to the information package (IP) in its different versions (SIP, AIP, DIP). The resulting structure of the IP includes checksums, original files, logs, transfer documentation and XML metadata. The main purpose of this work is to show the background activities already carried out in institutions around the world, and to start a research project aiming to generate ideas and thoughts in the Latin American context.Este trabalho relaciona a experiência inicial de testar uma estrutura adequada para a preservação de documentos digitais em um arquivo ou repositório. Numerosos antecedentes de estruturas similares são reconhecidos e, dentre eles, três experiências de sucesso dedicadas a conectar um repositório com ferramentas capazes de garantir a preservação digital de conteúdos seguindo o modelo OAIS, ISO 14721 (2012) são brevemente descritas. Depois de descrever estes três modelos considerados mais relevantes, um protótipo é contada em evidência em repositórios gerenciados em PrEBi-SEDICI (UNLP) com DSpace, Archivematica e ferramentas ArchivesSpace no repositório DSpace está a cargo de renda e entrega de conteúdo digital enquanto a estrutura do Archivematica realiza atividades de preservação digital através da implementação de um conjunto de microsserviços, que atuam sobre uma estrutura conceitual assimilável ao pacote de informações (IP) em suas diferentes versões. A estrutura física resultante do pacote de informações em suas diferentes versões (SIP, AIP, DIP) inclui arquivos, soma de verificação, logs, documentação da transferência e metadados em uma estrutura XML. Este trabalho não tem mais pretensões do que mostrar os antecedentes e o início de um trabalho de pesquisa com o objetivo de gerar consultas e reflexões no contexto latino-americano, onde essas questões são incipientes.Este trabajo relata la experiencia inicial de prueba de una estructura apta para la preservación de documentos digitales en un archivo o repositorio. Se reconocen numerosos antecedentes de estructuras similares y, entre ellas, se describen brevemente tres experiencias exitosas dedicadas a conectar un repositorio con herramientas capaces de asegurar la preservación digital de los contenidos siguiendo el modelo OAIS, norma ISO 14721 (2012). Tras la descripción de estos tres modelos considerados más relevantes, se relata un prototipo en prueba en los repositorios gestionados en PREBI-SEDICI (UNLP) con las herramientas DSpace, Archivematica y ArchivesSpace, en el que el repositorio en DSpace está encargado del ingreso y la entrega de los contenidos digitales mientras que la estructura de Archivematica realiza las actividades de preservación digital a través de la implementación de un conjunto de microservicios, que actúan sobre una estructura conceptual asimilable al paquete de información (IP) en sus distintas versiones. La estructura física resultante del paquete de información en sus diferentes versiones (SIP, AIP, DIP) incluye archivos, checksum, logs, documentación de la transferencia y metadatos en una estructura XML. Este trabajo no tiene más pretensiones que mostrar los antecedentes y el inicio de un trabajo de investigación con el objetivo de generar consultas y reflexiones en el contexto latinoamericano, donde estas temáticas son incipientes.Proyecto de Enlace de Biblioteca