909 research outputs found
Penalized functional spatial regression
This paper is focus on spatial functional variables whose observa- tions are realizations of a spatio-temporal functional process. In this context, a new smoothing method for functional data presenting spa- tial dependence is proposed. This approach is based on a P-spline estimation of a functional spatial regression model. As alternative to other geostatistical smoothing methods (kriging and kernel smooth- ing, among others), the proposed P-spline approach can be used to estimate the functional form of a set of sample paths observed only at a finite set of time points, and also to predict the corresponding func- tional variable at a new location within the plane of study. In order to test the good performance of the proposed method, two simulation studies and an application with real data will be developed and the results will be compared with functional kriging.Financial support from the project P11-FQM-8068 from Consejería de Innovación, Ciencia y Empresa. Junta de Andalucía, Spain and the projects MTM2013-47929-P and MTM 2011-28285-C02-C2 from Secretaría de Estado Investigación, Desarrollo e
Innovación, Ministerio de Economía y Competitividad, Spain
Reutilización de Residuos Sólidos en la Promoción de la Cultura Ambiental
This study aimed to propose a strategic plan for the reuse of solid waste in promoting environmental culture in the sixth grade students of Basic Estadal "Chaparral" School, located in the municipality Pedraza Barinas State for the year school from 2015 to 2016. Research of quantitative nature, descriptive in the form of feasible project, divided into five phases for the diagnosis, feasibility, design, implementation and evaluation of results in the implementation of a strategic plan based on the reuse of solid waste. In relation to the population, this is limited to five teachers, selecting all for the sample as a small universe. As the survey technique was used a questionnaire type instrument 8 questions in Likert scale of three response options was applied. For the formula reliability coefficient (α) Cronbach's alpha, validity through expert judgment was applied. In conclusion a proposal called Strategic Plan for reuse of solid waste in promoting environmental culture in the sixth grade students of Basic Estadal "Chaparral" School during the 2015-2016 school year was set
Comparative study of different B-spline approaches for functional data
The sample observations of a functional variable are functions that come from the
observation of a statistical variable in a continuous argument that in most cases is the
time. But in practice, the sample functions are observed in a finite set of points. Then, the
first step in functional data analysis is to reconstruct the functional form of sample curves
from discrete observations. The sample curves are usually represented in terms of basis
functions and the basis coefficients are fitted by interpolation, when data are observed
without error, or by least squares approximation, in the other case. The main purpose of
this paper is to compare three different approaches for estimating smooth sample curves
observed with error in terms of B-spline basis: regression splines (non-penalized least
squares approximation), smoothing splines (continuous roughness penalty) and P-splines
(discrete roughness penalty). The performance of these spline smoothing approaches is
studied via a simulation study and several applications with real data. Cross-validation and
generalized cross-validation are adapted to select a common smoothing parameter for all
sample curves with the roughness penalty approaches. From the results, it is concluded
that both penalized approaches drastically reduced the mean squared errors with respect
to the original smooth sample curves with P-splines giving the best approximations with
less computational cost.Project MTM2010-20502 from Dirección General de Investigación, Ministerio de Educación y Ciencia SpainProject P11-FQM-8068 from Consejería de Innovación, Ciencia y Empresa. Junta de Andalucía, Spai
Prediction of functional data with spatial dependence: a penalized approach
This paper is focus on spatial functional variables whose observations are a set of spatially correlated
sample curves obtained as realizations of a spatio-temporal
stochastic process. In this context, as alternative to other
geostatistical techniques (kriging, kernel smoothing,
among others), a new method to predict the curves of
temporal evolution of the process at unsampled locations
and also the surfaces of geographical evolution of the
variable at unobserved time points is proposed. In order to
test the good performance of the proposed method, two
simulation studies and an application with real climatological data have been carried out. Finally, the results were
compared with ordinary functional kriging.Project P11-FQM-8068 from Consejería de Innovación, Ciencia y Empresa, Junta de Andalucía, SpainProjects MTM2013-47929-P, MTM2011-28285-C02-C2 and MTM 2014-52184-P from Secretaría de
Estado Investigación, Desarrollo e Innovación, Ministerio de Economía y Competitividad, Spai
Schizotypal personality and semantic functioning: Revisiting category fluency effects in a subclinical sample
Semantic disturbances have been proposed as a possible cause of formal thought disorder in schizophrenia. Fluency tasks, in which volunteers are asked to produce as many exemplars as they can for a given category during one minute, are usually applied to the assessment of semantic processing. However, studies associating fluency and proneness to psychosis have provided conflicting results so it is not clear whether these disturbances can be identified at subclinical stages. We conducted two experiments. In the first one, 71 volunteers completed written category fluency tasks with four semantic categories (animals, fruits, clothing and vehicles). In the second experiment, 77 new participants completed oral category and phonological fluency tasks (words starting with f, t, p and c). In both experiments, we assessed schizotypal personality and vocabulary size. Schizotypal traits were not reliably associated with either productivity or originality of the responses in any experiment. In contrast, vocabulary size significantly predicted the participants' scores in all the tasks. Along with results of other recent studies, our data cast doubt on the reliability of previous observations pointing out an association between schizotypy and lexical-semantic disturbances, at least in relation to productivity and originality in fluency tests
Functional PCA and Base-Line Logit Models
In many statistical applications data are curves measured as functions of a
continuous parameter as time. Despite of their functional nature and due to discrete time observation, these type of data are usually analyzed with multivariate statistical
methods that do not take into account the high correlation between observations of a
single curve at nearby time points. Functional data analysis methodologies have been
developed to solve these type of problems. In order to predict the class membership
(multi-category response variable) associated to an observed curve (functional data),
a functional generalized logit model is proposed. Base-line category logit formula-
tions will be considered and their estimation based on basis expansions of the sample
curves of the functional predictor and parameters. Functional principal component
analysis will be used to get an accurate estimation of the functional parameters and
to classify sample curves in the categories of the response variable. The good performance of the proposed methodology will be studied by developing an experimental
study with simulated and real data.Projects MTM2010-20502 from Dirección General de Investigación del MEC SpainFQM-08068 from Consejería de Innovación, Ciencia y Empresa de la Junta de Andalucía Spai
Impacto de la Educación Musical : una revisión de la literatura científica
Este artículo estudia el impacto de la educación musical cursada en las enseñanzas obligatorias a partir de una revisión de la literatura académica existente. La búsqueda en bases de datos especializadas proporcionó un total de 25 artículos publicados durante el periodo 2005 - 2016. Tras analizarlos se establecieron dos categorías de impacto: DENTRO, en relación con la propia disciplina y FUERA, con implicaciones más allá de la disciplina. Buena parte de las publicaciones analizadas contemplaron el impacto de acuerdo con temáticas que sobrepasan lo que es estrictamente la educación musical obligatoria abarcando aspectos personales, intelectuales y/o sociales. En consecuencia, se presenta una conceptualización de impacto en educación musical que va más allá de los aspectos mensurables asociados a las políticas educativas de reforma.This paper examines the impact of school music education through an academic literature review. The search in specialized databases provided a total of 25 papers published during 2005 - 2016. The analysis revealed two categories in relation to impact: IN, that included those issues within the discipline, and OUT, with implications beyond it. Many of the analysed publications considered the impact based on topics that go beyond what strictly school music education is, including personal, intellectual and/or social aspects. This study presents a conceptualization of impact on music education that surpasses the measurable aspects associated with educational policy reforms
Penalized function-on-function partial leastsquares regression
This paper deals with the "function-on-function'" or "fully functional" linear regression problem. We address the problem by proposing a novel penalized Function-on-Function Partial Least-Squares (pFFPLS) approach that imposes smoothness on the PLS weights. Our proposal introduces an appropriate finite-dimensional functional space with an associated set of bases on which to represent the data and controls smoothness with a roughness penalty operator. Penalizing the PLS weights imposes smoothness on the resulting coefficient function, improving its interpretability. In a simulation study, we demonstrate the advantages of pFFPLS compared to non-penalized FFPLS. Our comparisons indicate a higher accuracy of pFFPLS when predicting the response and estimating the true coefficient function from which the data were generated. We also illustrate the advantages of our proposal with two case studies involving two well-known datasets from the functional data analysis literature. In the first one, we predict log precipitation curves from the yearly temperature profiles recorded in 35 weather stations in Canada. In the second case study, we predict the hip angle profiles during a gait cycle of children from their corresponding knee angle profiles
Human THO–Sin3A interaction reveals new mechanisms to prevent R-loops that cause genome instability
R-loops, formed by co-transcriptional DNA–RNA hybrids and a displaced DNA single strand (ssDNA), fulfill certain positive regulatory roles but are also a source of genomic instability. One key cellular mechanism to prevent R-loop accumulation centers on the conserved THO/TREX complex, an RNA-binding factor involved in transcription elongation and RNA export that contributes to messenger ribonucleoprotein (mRNP) assembly, but whose precise function is still unclear. To understand how THO restrains harmful R-loops, we searched for new THO-interacting factors. We found that human THO interacts with the Sin3A histone deacetylase complex to suppress co-transcriptional R-loops, DNA damage, and replication impairment. Functional analyses show that histone hypo-acetylation prevents accumulation of harmful R-loops and RNA-mediated genomic instability. Diminished histone deacetylase activity in THO- and Sin3A-depleted cell lines correlates with increased R-loop formation, genomic instability, and replication fork stalling. Our study thus uncovers physical and functional crosstalk between RNA-binding factors and chromatin modifiers with a major role in preventing R-loop formation and RNA-mediated genome instability.European Research Council ERC2014 AdG669898 TARLOOPMinisterio de Economía y Competitividad BFU2013-42918-P, BFU2016-75058-PJunta de Andalucía BIO123
Challenges of teacher educators: Professional experiences of a beginning educator and researcher
Este artículo pretende examinar los retos experimentados por una profesora universitaria novel
durante sus dos primeros años de ejercicio en una institución española. La investigación
narrativa se utilizó para indagar en la formación de su identidad profesional en el contexto
universitario y para co-construir, a través de un proceso de reflexión colaborativo, relatos que
focalizan en incidentes críticos acaecidos durante su fase introductoria en la universidad. En una
fase posterior, dichos incidentes fueron analizados por la propia autora, quien definió tres
temas recurrentes: el shock de la praxis experimentado durante su fase inicial al contexto
universitario, la adaptación de su enfoque docente al nuevo entorno laboral y la actividad
investigadora llevada a cabo y requerida en la universidad. Los resultados revelan la
importancia de proporcionar al profesorado universitario novel el apoyo y las herramientas
necesarias con las que facilitar su adaptación a la universidad y contribuir a su desarrollo
profesional. El artículo finaliza con una reflexión en torno a iniciativas formales e informales
que podrían ser llevadas a cabo para sobreponerse a los retos del contexto universitario.This study seeks to examine the challenges experienced by a beginning teacher educator during
her first two years in the profession at a Spanish institution. Narrative inquiry was used to
provide insights into the formation of her professional identity at the university context. This
methodology was also utilized to co-construct, through a collaborative process of reflection,
stories which focus on critical events occurred during her introductory phase at the tertiary level.
In a subsequent phase, these incidents were analysed by the author, who defined three recurrent
themes: the praxis-shock experienced during her initial phase in the university setting, the
adaptation of her teaching approach to the new working context and the research activity carried
out and required at the university. The results reveal the importance of providing beginning
teacher educators with the support and the tools needed to ease their adaptation to the university
context and contribute to their professional development. This article concludes with a reflection
about the formal and informal initiatives that might be carried out to deal with the challenges in
the university context.Grupo FORCE (HUM-386). Departamento de Didáctica y Organización Escolar de la Universidad de Granad
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