Search results for " Statistical"
showing 10 items of 1649 documents
Predictive signs and indicators of aggressiveness and violence: a comparison between a group of adolescents attending an external penal area, a group…
2006
Aim. We considered the spreading and the increasing of aggressive and violent behaviours. The most of them have two common roots: lack of actual motivation and brutality. Our research intends to detect specific indicators and predictive signs of violent and aggressive behaviours. In order to this, scientific literature shows that the most reliable indicators and predictive signs are linked to structural personality features (e.g. defensive strategies, impulse control). Methods. This cross sectional study compares a group of 26 male adolescents with Conduct Disorder (F91.8), a group of 29 male patients with Borderline Personality Disorder (F60.31) and a group of 33 male prisoners with Antiso…
The Dynamical Problem for a Non Self-adjoint Hamiltonian
2012
After a compact overview of the standard mathematical presentations of the formalism of quantum mechanics using the language of C*- algebras and/or the language of Hilbert spaces we turn attention to the possible use of the language of Krein spaces.I n the context of the so-called three-Hilbert-space scenario involving the so-called PT-symmetric or quasi- Hermitian quantum models a few recent results are reviewed from this point of view, with particular focus on the quantum dynamics in the Schrodinger and Heisenberg representations.
ISLANDS TOURISM SEASONALITY
2015
The islands of the European Union, generally associated with the sun and sea, attract the great majority of tourist flows in the summer months. This characteristic is shared by all the islands, be they in the Mediterranean or in the Baltic. However, through detailed analysis and the use of specific indicators, it was demonstrated that some islands are increasingly developing winter tourism in an effort to improve the annual occupancy rate of beds and mitigate seasonality curves. This study examines some islands that are located in different seas of the European Union, at different latitudes and hence in different climatic zones. These islands are: Cyprus (CY), Sicily (IT), Madeira (PT), and…
Finite-size scaling of charge carrier mobility in disordered organic semiconductors
2016
Simulations of charge transport in amorphous semiconductors are often performed in microscopically sized systems. As a result, charge carrier mobilities become system-size dependent. We propose a simple method for extrapolating a macroscopic, nondispersive mobility from the system-size dependence of a microscopic one. The method is validated against a temperature-based extrapolation [A. Lukyanov and D. Andrienko, Phys. Rev. B 82, 193202 (2010)]. In addition, we provide an analytic estimate of system sizes required to perform nondispersive charge transport simulations in systems with finite charge carrier density, derived from a truncated Gaussian distribution. This estimate is not limited t…
Statistical methods for the comparison of measurements derived from orthodontic imaging
2000
Biometric comparison procedures for dental imaging methods with continuous outcome were reviewed, mainly concentrating on assessment and comparison of accuracy and precision according to the study design. Univariate graphical and numerical representations of corresponding deviations were summarized to derive a 'check list' of minimum information necessary to compare the measurement methods. The methods reviewed in this investigation are illustrated by the comparison of conventional (radiographic) cephalometry versus assessment using the DigiGraph in 50 female children. A paired t-test and the corresponding confidence interval approach were used to assess deviations in location of two imagin…
Error estimation and reduction with cross correlations
2010
Besides the well-known effect of autocorrelations in time series of Monte Carlo simulation data resulting from the underlying Markov process, using the same data pool for computing various estimates entails additional cross correlations. This effect, if not properly taken into account, leads to systematically wrong error estimates for combined quantities. Using a straightforward recipe of data analysis employing the jackknife or similar resampling techniques, such problems can be avoided. In addition, a covariance analysis allows for the formulation of optimal estimators with often significantly reduced variance as compared to more conventional averages.
Changes in Body Composition in Anorexia Nervosa : Predictors of Recovery and Treatment Outcome
2015
The restoration of body composition (BC) parameters is considered to be one of the most important goals in the treatment of patients with anorexia nervosa (AN). However, little is known about differences between AN diagnostic subtypes [restricting (AN-R) and binge/purging (AN-BP)] and weekly changes in BC during refeeding treatment. Therefore, the main objectives of our study were twofold: 1) to assess the changes in BC throughout nutritional treatment in an AN sample and 2) to analyze predictors of BC changes during treatment, as well as predictors of treatment outcome. The whole sample comprised 261 participants [118 adult females with AN (70 AN-R vs. 48 AN-BP), and 143 healthy controls].…
Comparative study to predict toxic modes of action of phenols from molecular structures.
2013
Quantitative structure-activity relationship models for the prediction of mode of toxic action (MOA) of 221 phenols to the ciliated protozoan Tetrahymena pyriformis using atom-based quadratic indices are reported. The phenols represent a variety of MOAs including polar narcotics, weak acid respiratory uncouplers, pro-electrophiles and soft electrophiles. Linear discriminant analysis (LDA), and four machine learning techniques (ML), namely k-nearest neighbours (k-NN), support vector machine (SVM), classification trees (CTs) and artificial neural networks (ANNs), have been used to develop several models with higher accuracies and predictive capabilities for distinguishing between four MOAs. M…
On the Left Ventricular Remodeling of Patients with Stenotic Aortic Valve: A Statistical Shape Analysis
2021
The left ventricle (LV) constantly changes its shape and function as a response to pathological conditions, and this process is known as remodeling. In the presence of aortic stenosis (AS), the degenerative process is not limited to the aortic valve but also involves the remodeling of LV. Statistical shape analysis (SSA) offers a powerful tool for the visualization and quantification of the geometrical and functional patterns of any anatomic changes. In this paper, a SSA method was developed to determine shape descriptors of the LV under different degrees of AS and thus to shed light on the mechanistic link between shape and function. A total of n=86 patients underwent computed tomography (…
The role of minimal access valve surgery in the elderly. A meta-analysis of observational studies
2016
Background Minimal access valve surgery, both mitral and aortic, may be related to improvement in specific post-operative outcomes, therefore may be beneficial for the subgroup of the elderly referred for valve surgery. Methods A systematic literature review identified several different studies, of which 6 fulfilled criteria for meta-analysis. Outcomes for a total of 1347 patients (675 conventional standard sternotomy and 672 minimally invasive valve surgery) were assessed with a meta-analysis using random effects modeling. Heterogeneity, subgroup analysis with quality scoring were also assessed. The primary endpoint was early mortality. Secondary endpoints included intra and post-operative…