Subsampling inference in cube root asymptotics with an application to Manski's maximum score estimator

Kim and Pollard (Annals of Statistics, 18 (1990) 191?219) showed that a general class of M-estimators converge at rate n1/3 rather than at the standard rate n1/2. Many times, this situation arises when the objective function is non-smooth. The limiting distribution is the (almost surely unique) random vector that maximizes a certain Gaussian process and is difficult to analyze analytically. In this paper, we propose the use of the subsampling method for inferential purposes. The general method is then applied to Manski?s maximum score estimator and its small sample performance is highlighted via a simulation study.Publicad

Development and validation of the Scale of Motives for Using Social Networking Sites (SMU-SNS) for adolescents and youths

Over the past decade, the Uses and Gratifications theory has driven research on the motives behind social media use. The three most commonly explored motives have been: maintaining relationships, seeking information, and entertainment. The aim of this study was to develop and validate the Scale of Motives for Using Social Networking Sites (SMU-SNS), a measure to assess a wider range of motives for using Social Networking Sites than have previously been researched. A multi-method design with different samples of high-school and university students was used. First, to develop the pool of items, a literature review and a focus group study (n = 48, age range = 16–21) was conducted. Second, to reduce and refine the pool of items a pilot study (n = 168, age range = 14–24) was performed. Third, a validation study (n = 1102, age range = 13–25) was conducted to assess the validity and reliability of the SMU-SNS. Cross-validation using EFA and CFA resulted in a final version comprising 27 items distributed in nine factors (Dating, New Friendships, Academic Purposes, Social Connectedness, Following and Monitoring Others, Entertainment, seeking Social Recognition, Self-expression, and seeking Information). Internal consistency was excellent and evidence of measurement invariance across gender and age was largely achieved. The SMU-SNS scores significantly correlated with other relevant variables, including age, gender, certain personality traits, social support, loneliness, and life satisfaction. Overall, findings supported the SMU-SNS as a valid and reliable measure to assess youth’s motives for using Social Networking Sites. Psychometric and general implications are discussed.Ministerio de Economía y CompetitividadMinisterio de Educación y Formación Profesiona

Extracción automática de caras en imágenes captadas con móviles Android

Estudi i implementació de la detecció de cares en imatges primerament en un entorn de PC i finalment aplicar aquest coneixement en la implementació d'una aplicació en el sistema operatiu Android

DESCRIPCIÓN DE LA ARQUITECTURA HISTÓRICA COLONIAL DE AREQUIPA Y SU RELACIÓN CON EL INTERÉS EN EL TURISTA EXTRANJERO – 2015

El presente trabajo de investigación tiene como objetivo general describir la arquitectura colonial de Arequipa y relacionarla con el interés que genera en los turistas extranjeros La hipótesis de investigación se ha planteado de la siguiente manera: Dado que los recursos de la arquitectura histórica colonial de Arequipa son numerosos, es probable que haya una relación significativa con el interés del turista extranjero por conocer nuestra ciudad, si se promociona adecuadamente nuestra riqueza cultural. En cuanto a la metodología, se ha optado por una investigación de tipo descriptivo y relacional, la población de estudio se determinó entre los turistas extranjeros que visitaron nuestra ciudad entre los meses de Mayo y Junio, cuya muestra estuvo representada por 399. Se aplicó el método hipotético deductivo y como técnicas se consideró la revisión documental y la encuesta. No cabe duda que los recursos turísticos de Arequipa son únicos en el mundo, pues la belleza de su diseño y diversidad de estilos, así como el uso del sillar en sus edificaciones la hacen singular y digna de ser admirada por los turistas extranjeros. Se ha podido determinar que el interés que muestran los turistas extranjeros por los monumentos arquitectónicos históricos coloniales de nuestra ciudad, es muy limitado, ya que un pequeño porcentaje de ellos así lo han manifestado, al considerar que el motivo principal de su visita a Arequipa, se ha realizado con esa finalidad. Por otra parte, la totalidad de turistas, han visitado la mayor parte de monumentos arquitectónicos históricos coloniales de nuestra ciudad, sin embargo, son pocos los que tienen conocimiento que el nombre de Ciudad Blanca, se debe al uso del sillar en sus construcciones, y a su vez, la mayoría no tenía conocimiento previo de su arquitectura histórica colonial antes de realizar su viaje

Los depósitos de talco y clorita magnesiana de la Sierra de las Estancias (Cordillera Bética, Almería, España)

15 páginas, 11 figuras, 5 tablas.[ES] Los depósitos de talco y clorita magnesiana de la Sierra de las Estancias se enclavan en metapelitas y mármoles, pertenecientes a la cobertera triásica de la Unidad de Granja (Complejo Alpujárride). El metamorfismo de esta Unidad alcanza el grado medio. Las mineralizaciones están constituidas por tres tipos principales de rocas: talcocitas, clorititas talcosas y clorititas. Los talcos son de composición química muy próxima a la ideal [Mg3Si4010(OH)2]. Las cloritas corresponden a clinocloro y se caracterizan por poseer una razón Mg/(Mg + Fe) extremadamente alta ( > 0,98). Se establecen dos grupos principales de mineralizaciones: estratoligadas y filonianas. Las mineralizaciones estratoligadas se localizan en la zona de tránsito entre metapelitas (muro) y mármoles (techo), y en la parte inferior del paquete marmóreo. De muro a techo, las mineralizaciones muestran una variación gradual mineralógica y química, esta última caracterizada por un progresivo aumento en Mg y razón Mg/(Mg + Fe), y una disminución en el contenido en K20 y razón Al/Mg. La mayor parte de las mineralizaciones estratoligadas se han formado, durante el metamorfismo alpino, por transformación de sedimentos de composición muy rica en magnesio (probablemente «mudstones» evaporíticos). Una pequeña parte de este tipo de mineralizaciones y las de carácter filoniano se originan por removilización de los depósitos estratoligados.[EN] The talc and magnesium chlorite deposits of Sierra de Las Estancias occur in metapelites and marbles belonging to the Triassic cover of the Granja Unit (Alpujarride Complex). Metamorphism of this Unit reaches medium grade. The mineralizations are composed of talcites, talc chloritites and chloritites. The talc has a chemical composition very close to the ideal formula Mg3Si4010(OH)2]. The chlorite correspond to clinochloro and is characterized by an extremely high Mg/(Mg + Fe) ratio ( > 0.98). Two main groups of mineralizations are established: strata-bound and vein deposits. The first one is located in the transition zone between metapelites (bottom) and marbles (top) and in the lower part of the marble member. From botton to top, the mineralizations show a gradual mineralogical and chemical variation, the latter characterized by a progressive increase in Mg and in the Mg/(Mg + Fe) ratio, and by a decrease in K20 content and in the Al/Mg ratio. Most of the strata-bound mineralizations were formed during the Alpine metamorphism by the transformation of sediments very rich in magnesium (probably evaporite mudstones). A small part of this type of mineralizations and those of vein character originate by remobilization of the strata-bound deposits.Este trabajo ha sido subvencionado por el Instituto de Fomento de Andalucía, por el Proyecto n.O PB85-0385 de la CAICYT y los Grupos de Investigación de la Junta de Andalucía n. OS 4028 y 4065. Agradecemos al Dr. J. M. Martínez Martínez, del Inst. Andaluz de Geología Mediterránea (CSIG-Univ. Granada), la ayuda prestada en los trabajos de campo. Asimismo, agradecemos las útiles sugerencias y comentarios efectuados por el Dr. E. Galán, de la Universidad de Sevilla.Peer reviewe

Validation of self reported diagnosis of hypertension in a cohort of university graduates in Spain

BACKGROUND: The search for risk factors of hypertension requires the study of large populations. Sometimes, the only feasible way of studying these populations is to rely on self-reported data of the outcome. The objective of this study was to evaluate validity of self-reported diagnosis of hypertension in a cohort of university graduates in Spain. METHODS: The Seguimiento Universidad de Navarra (SUN) Study is a cohort of more than 15,000 university graduates in Spain. We selected a random sample of 79 cohort participants who reported a diagnosis of hypertension and 48 participants who did not report such diagnosis (76% participation proportion). Then, we compared information on the self-reported diagnosis of hypertension and hypertension status as assessed through two personal blood pressure measurements and an interview. Additionally, we compared self-reported and measured blood pressure levels with intraclass correlation coefficients and the survival-agreement plot. RESULTS: From those 79 reporting a diagnosis of hypertension, 65 (82.3%, 95% CI 72.8–92.8) were confirmed through conventional measurement of blood pressure and the interview. From those 48 that did not report a diagnosis of hypertension, 41 (85.4%, 95% CI 72.4–89.1) were confirmed as non hypertensives. Results were similar among men and women, but were worse for overweight and obese individuals, and for those with a family history of hypertension. The agreement between self-reported and measured blood pressure levels (as a continuous variable), as estimated by the intraclass correlation coefficient, was 0.35 for both systolic and diastolic blood pressure. CONCLUSION: Self-reported hypertension among highly educated participants in a cohort study is a relatively valid tool to assess the hypertensive status of participants. However, the investigators should be cautious when using self-reported blood pressure values

Características físicoquímicas de sedimentos de lagunas situadas en las Zonas Externas de las Béticas Occidentales

In the western External Betics several temporal saline water bodies (playa-lakes) constitute singular environments that are pro-tected due to their ecological and hydrological values. Changes in their hydrological status due to both natural and human-induced changes alter the characteristics of their sediments. A detailed de-termination of the pH and electrical conductivity in the sediments of six playa-lakes within a range of degradation statuses was made in this study. The detailed examination of such geochemical variables has allowed us to establish three categories of degradation in the studied systems. Our results highlight the extreme vulnerability of this playa-lakes caused mainly by human activities, particularly tho-se related to land-use change for agriculture, as well as the necessity of its protection based on scientific criteriaEn las Zonas Externas de las Béticas occidentales varias masas de agua salinas temporales (lagunas tipo playa) constituyen ambientes singulares que se encuentran protegidos por sus valores ecológicos e hidrológicos. Las variaciones en su estado hidrológico debido a cam-bios naturales o inducidos por el hombre alteran las características de sus sedimentos. En este estudio se realizó una determinación de-tallada del pH y la conductividad eléctrica en los sedimentos de seis lagunas que presentan un rango variable de estados de degradación. El examen de tales variables geoquímicas nos ha permitido establecer tres categorías de degradación en los sistemas estudiados. Nuestros resultados destacan la extrema vulnerabilidad de estas playas causa-da principalmente por actividades humanas, particularmente aque-llas relacionadas con el cambio de uso de suelo para la agricultura, así como la necesidad de su protección con base en criterios científico

Systematic review of the current state of research on Online Social Networks: Taxonomy on experience of use

La generalización del uso de redes sociales en jóvenes ha supuesto un incremento notable de las publicaciones sobre ellas y sobre sus efectos en el desarrollo psicosocial de los usuarios. Las tentativas previas de revisión panorámica sobre redes quedaron desfasadas y no aportan una visión comprehensiva de la complejidad de la experiencia de uso. Los objetivos de esta revisión sistemática actualizada fueron: identificar estudios cuantitativos sobre redes; construir una taxonomía sobre la experiencia de uso; y clasificar las variables estudiadas en temas y subtemas. La búsqueda y revisión de literatura siguiendo la estrategia PICoS identificó 546 estudios que cumplían los criterios de inclusión. La taxonomía incluyó nueve grandes temáticas investigadas: descripción y cuantificación del uso; actividades y tipos de uso; percepción y actitudes influyentes en el uso; red social de contactos; necesidades y motivos de uso; gestión del perfil y privacidad; procesos sociales; procesos identitarios; y procesos cognitivos-emocionales. Los tres temas más estudiados fueron: la descripción y cuantificación del uso; las actividades y tipos de uso; y los procesos sociales relacionados con el uso. Se detalla la clasificación, cuantificación e integración de las diversas variables estudiadas sobre la experiencia de uso. Las diferentes tradiciones de estudio, así como las lagunas, problemas y retos de la investigación sobre redes son discutidas. Dicha taxonomía será de utilidad para que investigadores puedan encuadrar mejor los objetivos de futuros estudios.The widespread use of online social networks (OSN) among young people has been accompanied by an increase of publications about them and their effects on the psychosocial development of users. Previous panoramic reviews on OSN research are now outdated and do not provide a comprehensive view of the complexity of the user experience. The aims of this systematic review were three: to identify quantitative studies on OSN; to build a taxonomy about the user experience; and to classify studied variables in the topics and subtopics. The literature search and review according to PICoS strategy led to 546 identified publications that met the eligibility criteria. The taxonomy included nine major topics: overall use; activities and types of use; perceptions and attitudes OSN; the social network of online contacts; needs and motives for use; profile and privacy management; social processes; identity processes; and cognitive-emotional processes related to use of OSN. The three most studied topics were: overall use; activities and types of use; and social processes related to use of OSN. Classification and quantification of the different variables studied about the users’ experience is detailed. Several theoretical perspectives are discussed, as well as the gaps and challenges in OSN research. The proposed taxonomy could be useful for researchers to better delineate the aims of future studies.Ministerio de Economía y Competitividad de España PSI 2015-64211-

Prevalence of superficial interdigital mycosis in a runners section of the “Maraton Popular de Madrid”

In this study it was tried to evaluate the incidence of interdigital superficial mycosis (tinea pedis) in the participant runners in the Popular Marathon of Madrid. The evaluation consisted of a collection of observed data of the foot, together with a dermatological examination with Wood lamp in 4º interdigital space and takes mycological culture, to 66 individuals, runners with ridge in the MAPOMA. The obtained microbiological results were, Trichophytum and Yeast was the prevalent in the sample, and that are in many cases in association with another pathogen, and that almost 90% of the total sample presented 4º interdigital space pathogenic and/or polluting. Therefore, the tinea pedis and interdigital candidiasis, in sportsmen is a risk factor to consider on the part of the podologyst, since is present of silent form and in many occasions it does not have the suitable treatment.In this study it was tried to evaluate the incidence of interdigital superficial mycosis (tinea pedis) in the participant runners in the Popular Marathon of Madrid. The evaluation consisted of a collection of observed data of the foot, together with a dermatological examination with Wood lamp in 4º interdigital space and takes mycological culture, to 66 individuals, runners with ridge in the MAPOMA. The obtained microbiological results were, Trichophytum and Yeast was the prevalent in the sample, and that are in many cases in association with another pathogen, and that almost 90% of the total sample presented 4º interdigital space pathogenic and/or polluting. Therefore, the tinea pedis and interdigital candidiasis, in sportsmen is a risk factor to consider on the part of the podologyst, since is present of silent form and in many occasions it does not have the suitable treatment