5 research outputs found
Marginal zero-inflated regression models for count data
No full textData sets with excess zeroes are frequently analyzed in many disciplines. A common framework used to analyze such data is the zero-inflated (ZI) regression model. It mixes a degenerate distribution with point mass at zero with a non-degenerate distribution. The estimates from ZI models quantify the effects of covariates on the means of latent random variables, which are often not the quantities of primary interest. Recently, marginal zero-inflated Poisson (MZIP; Long et al. [A marginalized zero-inflated Poisson regression model with overall exposure effects. Stat. Med. 33 (2014), pp. 5151–5165]) and negative binomial (MZINB; Preisser et al., 2016) models have been introduced that model the mean response directly. These models yield covariate effects that have simple interpretations that are, for many applications, more appealing than those available from ZI regression. This paper outlines a general framework for marginal zero-inflated models where the latent distribution is a member of the exponential dispersion family, focusing on common distributions for count data. In particular, our discussion includes the marginal zero-inflated binomial (MZIB) model, which has not been discussed previously. The details of maximum likelihood estimation via the EM algorithm are presented and the properties of the estimators as well as Wald and likelihood ratio-based inference are examined via simulation. Two examples presented illustrate the advantages of MZIP, MZINB, and MZIB models for practical data analysis.</p
An Ontology and Semantic Web Service for Quantum Chemistry Calculations
No full textThe purpose of this
article is to present an ontology, termed OntoCompChem,
for quantum chemistry calculations as performed by the Gaussian quantum
chemistry software, as well as a semantic web service named MolHub.
The OntoCompChem ontology has been developed based on the semantics
of concepts specified in the CompChem convention of Chemical Markup
Language (CML) and by extending the Gainesville Core (GNVC) ontology.
MolHub is developed in order to establish semantic interoperability
between different tools used in quantum chemistry and thermochemistry
calculations, and as such is integrated into the J-Park Simulator
(JPS)a multidomain interactive simulation platform and expert
system. It uses the OntoCompChem ontology and implements a formal
language based on propositional logic as a part of its query engine,
which verifies satisfiability through reasoning. This paper also presents
a NASA polynomial use-case scenario to demonstrate semantic interoperability
between Gaussian and a tool for thermodynamic data calculations within
MolHub
Emotions experienced by middle school students in physics and chemistry classes
No full textgraficas, tablasLas emociones en la clase de ciencias cumplen un papel fundamental como mediadoras en el aprendizaje, de este modo, inciden significativamente en la conducta, habilidades, capacidades y contexto escolar. Por lo tanto, en la presente investigación se estudian las emociones experimentadas por los estudiantes de la media en las clases de física y química del Liceo Arquidiocesano de Nuestra Señora (LANS), con el fin de identificar las emociones más frecuentes y las causas que las generan. En la investigación se involucran diferentes sociodemográficos de interés como la edad, sexo, estrato socioeconómico, tipo de clase, tipo de asignatura, entre otros. El desarrollo metodológico está enmarcado dentro del modelo cuantitativo, bajo lineamientos de un diseño no experimental, transeccional y correlacional, el cual permitió la creación y reducción de un instrumento que fue validado por expertos y usado para medir la frecuencia de emociones presentes en los estudiantes. Como resultado se obtiene la identificación de las emociones más frecuentes en la clase de ciencias, las principales causas que estimulan dichas emociones y finalmente se realiza una propuesta metodológica para el manejo de las emociones en el aula con la que se pretende potenciar las emociones positivas que favorezcan el aprendizaje de los estudiantes (Texto tomado de la fuente)Emotions in science class play a fundamental role as mediators in learning, thus, they have a significant impact on behavior, skills, abilities and school context. Therefore, the present research studies the emotions experienced by middle school students in physics and chemistry classes at the Liceo Arquidiocesano de Nuestra Señora (LANS), in order to identify the most frequent emotions and the causes that generate them. The research involves different sociodemographics of interest such as age, sex, socioeconomic stratum, type of class, type of subject, among others. The methodological development is framed within the quantitative model, under the guidelines of a non-experimental, transectional and correlational design, which allowed the creation and reduction of an instrument that was validated by experts and used to measure the frequency of emotions present in the students. As a result, the most frequent emotions in the science class are identified, the main causes that stimulate these emotions and finally a methodological proposal is made for the management of emotions in the classroom with which it is intended to enhance positive emotions that favor student learning.MaestríaMagíster en Enseñanza de las Ciencias Exactas y NaturalesCon el fin de identificar las emociones más frecuentes y las causas que las generan. En la investigación se involucran diferentes sociodemográficos de interés como la edad, sexo, estrato socioeconómico, tipo de clase, tipo de asignatura, entre otros. El desarrollo metodológico está enmarcado dentro del modelo cuantitativo, bajo lineamientos de un diseño no experimental, transeccional y correlacional, el cual permitió la creación y reducción de un instrumento que fue validado por expertos y usado para medir la frecuencia de emociones presentes en los estudiantes.Enseñanza y aprendizaje de las ciencias exactas y naturalesMatemáticas Y Estadística.Sede Manizale
