Search results for "Discriminant"
showing 10 items of 344 documents
Active contour algorithm with discriminant analysis for delineating tumors in positron emission tomography.
2019
Abstract In the context of cancer delineation using positron emission tomography datasets, we present an innovative approach which purpose is to tackle the real-time, three-dimensional segmentation task in a full, or at least nearly full automatized way. The approach comprises a preliminary initialization phase where the user highlights a region of interest around the cancer on just one slice of the tomographic dataset. The algorithm takes care of identifying an optimal and user-independent region of interest around the anomalous tissue and located on the slice containing the highest standardized uptake value so to start the successive segmentation task. The three-dimensional volume is then…
Trait self-control and self-discipline : Structure, validity, and invariance across national groups
2021
The aim of the present study was to test the validity of the Brief Self-Control Scale (BSCS; Tangney, Baumeister and Boone 2004) including its dimensional structure based on competing one- and two-factor models, discriminant validity from the conceptually-related self-discipline construct, invariance across multiple samples from different national groups, and predictive validity with respect to health-related behaviors. Samples of undergraduate students (total N = 1282) from four national groups completed the brief self-control scale, the self-discipline scale from the NEO-PI-R, and self-report measures of binge drinking, exercise, and healthy eating. Confirmatory factor analytic models sup…
The process of identifying gifted children in elementary education: Teachers’ evaluations of creativity
2012
This study describes the importance of creativity in the identification of gifted elementary-aged children and presents the process of validating a scale for rating the creativity of the students through the teachers’ responses. The results show the instrument’s unifactorial structure, satisfactory levels of internal consistency, as well as convergent and discriminant validity. The results are discussed in terms of their implications for the work of school psychologists.
Introduction and Psychometric Validation of the Resilience and Strain Questionnaire (ResQ-Care)— A Scale on the Ratio of Informal Caregivers' Resilie…
2021
Background: Informal caregivers are a particularly vulnerable population at risk for adverse health outcomes. Likewise, there are many scales available assessing individual caregiver burden and stress. Recently, resilience in caregivers gained increasing interest and scales started to assess resilience factors as well. Drawing on a homeostatic model, we developed a scale assessing both caregivers' stress and resilience factors. We propose four scales, two covering stress and two covering resilience factors, in addition to a sociodemographic basic scale. Based on the stress:resilience ratio, the individual risk of adverse health outcomes and suggestions for interventions can be derived.Metho…
Perceived Vulnerability to Disease Questionnaire: Factor structure, psychometric properties and gender differences
2016
Abstract The evolutionary psychological approach links evolved mechanisms of disease-avoidance to prejudices against individuals perceived as a threat to health. Perceived vulnerability to disease works as an adaptive strategy which explains why individuals perceived as a source of contagion are avoided. The self-report Perceived Vulnerability to Disease Questionnaire, PVDQ, is one of the most widely used to measure subjective vulnerability to disease, however, neither test–retest reliability has been studied nor has factor structure been confirmed so far in this questionnaire. In the present study, a sample of 878 participants completed the PVDQ. Subsamples also completed different scales …
Classification of pumpkin seed oils according to their species and genetic variety by attenuated total reflection Fourier-transform infrared spectros…
2011
Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR), followed by multivariate treatment of the spectral data, was used to classify seed oils of the genus Cucurbita (pumpkins) according to their species as C. maxima, C. pepo, and C. moschata. Also, C. moschata seed oils were classified according to their genetic variety as RG, Inivit C-88, and Inivit C-2000. Up to 23 wavelength regions were selected on the spectra, each region corresponding to a peak or shoulder. The normalized absorbance peak areas within these regions were used as predictors. Using linear discriminant analysis (LDA), an excellent resolution among all categories concerning both Cucurbita species a…
Compactifying Torus Fibrations Over Integral Affine Manifolds with Singularities
2021
This is an announcement of the following construction: given an integral affine manifold B with singularities, we build a topological space X which is a torus fibration over B. The main new feature of the fibration X → B is that it has the discriminant in codimension 2.
Stable Images and Discriminants
2020
We show that the discriminant/image of a stable perturbation of a germ of finite \(\mathcal {A}\)-codimension is a hypersurface with the homotopy type of a wedge of spheres in middle dimension, provided the target dimension does not exceed the source dimension by more than one. The number of spheres in the wedge is called the discriminant Milnor number/image Milnor number. We prove a lemma showing how to calculate this number, and show that when the target dimension does not exceed the source dimension, the discriminant Milnor number and the \(\mathcal {A}\)-codimension obey the “Milnor–Tjurina relation” familiar in the case of isolated hypersurface singularities. This relation remains conj…
Logarithmic Vector Fields and the Severi Strata in the Discriminant
2017
The discriminant, D, in the base of a miniversal deformation of an irreducible plane curve singularity, is partitioned according to the genus of the (singular) fibre, or, equivalently, by the sum of the delta invariants of the singular points of the fibre. The members of the partition are known as the Severi strata. The smallest is the δ-constant stratum, D(δ), where the genus of the fibre is 0. It is well known, by work of Givental’ and Varchenko, to be Lagrangian with respect to the symplectic form Ω obtained by pulling back the intersection form on the cohomology of the fibre via the period mapping. We show that the remaining Severi strata are also co-isotropic with respect to Ω, and mor…
Multivariate data analysis of quality parameters in drinking water.
2001
The quality of water destined for human consumption has been treated as a multivariate property. Since most of the quality parameters are obtained by applying analytical methods, the routine analytical laboratory (responsible for the accuracy of analytical data) has been treated as a process system for water quality estimation. Multivariate tools, based on principal component analysis (PCA) and partial least squares (PLS) regression, are used in the present paper to: (i) study the main factors of the latent data structure and (ii) characterize the water samples and the analytical methods in terms of multivariate quality control (MQC). Such tools could warn of both possible health risks rela…