Search results for "methods"
showing 10 items of 4526 documents
Ab initio study of the F centers in CaF2: Calculations of the optical absorption, diffusion and binding energies
1998
Abstract The ground electronic state of the F center in CaF 2 crystal, its optical absorption energy, the activation energy of thermal diffusion and M center dissociation to pair of F centers are calculated using the Hartree-Fock embedded molecular cluster method. Different pseudopotentials, basis sets, boundary conditions and two computer codes, EMBED96 and Gaussian94, are employed and their results compared.
The first milestone in psychoeducational intervention in Spain: the Medical and Educational Psychology Laboratory of the National Patronage for the H…
2017
espanolLa intervencion psicopedagogica terapeutica supone el inicio de una importante vertiente del trabajo psicotecnico en Espana, destacando especialmente la atencion al ambito infantil, que propiciara la creacion de instituciones como el Patronato Nacional de Anormales, que supondra un referente para el trabajo conjunto de profesionales del ambito medico, pedagogico y psicologico. Este trabajo analiza los primeros anos del Patronato, centrandose en sus objetivos e ideario de funcionamiento y, especialmente en la creacion en 1914 del Laboratorio Medico y de Psicologia Pedagogica y en el trabajo que alli realizaron autores proximos a la psiquiatria infantil como Rodriguez Lafora y Achucarr…
Assessment of somatoform disorders: a review of strategies and instruments.
2003
We provide an overview of methods and instruments developed for the assessment of somatoform disorders. Four diagnostic purposes have been identified: (i) classification according to a diagnostic system; (ii) screening for probable cases; (iii) dimensional measurement of syndrome severity; and (iv) assessment of associated clinical features. Existing instruments designed for each of these strategies are described, including specifications of their psychometric properties, particular features, advantages and disadvantages. A conclusion of this review is that the currently existing ‘family of assessment instruments’ in the field of somatoform disorders should be used to improve the comparabil…
An item response theory analysis of response stability in personality measurement
2001
An item response theory model of response stability is developed, based on the local independence principle. The model predicts response changes under repeated administrations of the same instrument using item and examinee parameter estimates as predictors. Real data were used to assess how the model functioned. Results indicated that the model predictions were approximately fulfilled. Limitations of the model and the empirical study are discussed.
Psychometric Properties of Two Brief Versions of the Hopkins Symptom Checklist: HSCL-5 and HSCL-10
2019
The Hopkins Symptom Checklist–25 (HSCL-25) is a widely applied measure of depression and anxiety. The present study examines two of its short forms—the HSCL-5 and HSCL-10, which have been proposed by previous research—in a representative sample of the German general population. To this end, we conducted exploratory and confirmatory analysis on two subsamples ( n = 1,246 and n = 1,216). Our results suggest that, compared with the HSCL-25, both short forms represent economical ways of assessing depression and anxiety. Model fit was good and correlations with established measures demonstrate convergent validity. Both HSCL short forms are strongly invariant across sex, and we found evidence fo…
Calculus Self-Efficacy Inventory : Its Development and Relationship with Approaches to Learning
2019
This study was framed within a quantitative research methodology to develop a concise measure of calculus self-efficacy with high psychometric properties. A survey research design was adopted in which 234 engineering and economics students rated their confidence in solving year-one calculus tasks on a 15-item inventory. The results of a series of exploratory factor analyses using minimum rank factor analysis for factor extraction, oblique promin rotation, and parallel analysis for retaining extracted factors revealed a one-factor solution of the model. The final 13-item inventory was unidimensional with all eigenvalues greater than 0.42, an average communality of 0.74, and a 62.55% variance…
Outcomes of a Teaching Learning Sequence on Modelling Surface Phenomena in Liquids
2023
In this paper we discuss the effects of modelling and computer simulation activities in promoting student use of lines of reasoning useful to explain proposed or observed situations. The activities are part of a structured Teaching/Learning Sequence on surface phenomena in liquids. We outline a model of liquid based on a mesoscopic approach, examples of computer simulations students can use during the activities, and we describe the Teaching/Learning Sequence. During the pedagogical activities, students can simulate the liquid behaviour by controlling many simulation parameters, such as the interaction intensity among liquid and solid particles. The results of the analysis of student answer…
Contextual perceived group threat and radical right-wing populist party preferences: Evidence from Switzerland
2016
Existing studies suggest that perceived group threat is an important influence on radical right-wing populist party preferences. However, most have focused on perceived group threat at the individual level, overlooking the ideological climate. I examine how an ideological climate of group threat perception as a contextual factor can shape individual preferences for radical right-wing populist party preferences. I argue that above and beyond personal perceived group threat, the prevalence of local perceived group threat exerts a normative influence on personal preferences. Using voting preferences for the Swiss People’s Party, I employ multilevel structural equation modeling to examine the …
Geographical variation in the exhaled volatile organic compounds.
2013
Breath-gas analysis has demonstrated that concentration profiles of volatile organic compounds (VOCs) could be used for detecting a variety of diseases, among them gastric cancer (GC) and peptic ulcer disease (PUD). Here, we explore how geographical variation affects the disease-specific changes in the chemical composition of breath samples, as compared to control states (less severe gastric conditions). Alveolar exhaled breath samples from 260 patients were collected at two remotely different geographic locations (China and Latvia), following similar breath-collection protocols. Each cohort included 130 patients that were matched in terms of diagnosis (37 GC/32 PUD/61 controls), average ag…
The optimal imaging test for diagnosis of acute pulmonary embolism: a second chance for lung scintigraphy?
2020
Ventilation–perfusion scintigraphy may continue to be the first-line diagnostic method for pulmonary embolism in institutions that can ensure its uninterrupted availability and the expertise in its interpretationhttps://bit.ly/2y3Dlhx