Search results for "Regression Analysis"
showing 10 items of 807 documents
Substituent effects on13C NMR parameters of chlorinated diphenyl ethers. A multiple linear regression analysis
1995
13C NMR chemical shifts and nJ(C,H) coupling constants of polychlorinated diphenyl ethers (PCDEs) were measured and analysed. The chlorine substituent effects on the chemical shifts and the coupling constants were determined by a multiple linear regression analysis. The 13C NMR chemical shifts depend on the conformational preferences in PCDEs. In addition to single substituent effects, corrective terms reflecting the conformational state of the molecule and the mutual steric interactions of two chlorine atoms had to be taken into account for the reliable prediction of the 13C chemical shifts. In contrast to chemical shifts, conformational effects play a minor role in the substituent effects…
What drives the helpfulness of online reviews? A deep learning study of sentiment analysis, pictorial content and reviewer expertise for mature desti…
2021
Los destinos turísticos se ven cada vez más afectados por la información relacionada con los viajes que se comparte a través de las redes sociales. Basándose en teorías de proceso dual sobre cómo los individuos procesan la información, este estudio examina el papel de las rutas de procesamiento de información central y periférica en la formación de las percepciones de los consumidores sobre la utilidad de las reseñas en línea de destinos maduros. Llevamos a cabo un proceso de dos pasos para abordar la utilidad percibida del contenido generado por el usuario, un análisis de sentimiento utilizando técnicas avanzadas de aprendizaje automático (aprendizaje profundo) y un análisis de regresión. …
More Than (Single) Text Comprehension? – On University Students’ Understanding of Multiple Documents
2020
The digital revolution has made a multitude of text documents from highly diverse perspectives on almost any topic easily available. Accordingly, the ability to integrate and evaluate information from different sources, known as multiple document comprehension, has become increasingly important. Because multiple document comprehension requires the integration of content and source information across texts, it is assumed to exceed the demands of single text comprehension due to the inclusion of two additional mental representations: the integrated situation model and the intertext model. To date, there is little empirical evidence on commonalities and differences between single text and mult…
Disentangling cardiovascular control mechanisms during head-down tilt via joint transfer entropy and self-entropy decompositions
2015
A full decomposition of the predictive entropy (PE) of the spontaneous variations of the heart period (HP) given systolic arterial pressure (SAP) and respiration (R) is proposed. The PE of HP is decomposed into the joint transfer entropy (JTE) from SAP and R to HP and self-entropy (SE) of HP. The SE is the sum of three terms quantifying the synergistic/redundant contributions of HP and SAP, when taken individually and jointly, to SE and one term conditioned on HP and SAP denoted as the conditional SE (CSE) of HP given SAP and R. The JTE from SAP and R to HP is the sum of two terms attributable to SAP or R plus an extra term describing the redundant/synergistic contribution to the JTE. All q…
Multi-dimensional Function Approximation and Regression Estimation
2002
In this communication, we generalize the Support Vector Machines (SVM) for regression estimation and function approximation to multi-dimensional problems. We propose a multi-dimensional Support Vector Regressor (MSVR) that uses a cost function with a hyperspherical insensitive zone, capable of obtaining better predictions than using an SVM independently for each dimension. The resolution of the MSVR is achieved by an iterative procedure over the Karush-Kuhn-Tucker conditions. The proposed algorithm is illustrated by computers experiments.
Optimization of the Surface Roughness Equation obtained by Al7136 End-Milling
2017
The aim of this paper is to optimize the regression equation of the surface roughness obtained by 7136 aluminium alloy machined by end-milling process. The surface roughness is dependent on certain process parameters, which can vary, causing in this way variations of the surface quality. The research method used in this paper is the experiment and the Taguchi design of experiment. The experiment was performed using an experimental stand, in which every step to get the purpose, is presented. The measurements were made using a portable surface roughness tester. In the first part of the paper the influence percentage of the involved parameters in the machining process, was determined. Then, a …
Applying Experimental Research Management to a Technological Process using Taguchi's Method
2018
Abstract The surface quality is dependent on certain cutting process parameters that can vary, causing variations on the surface roughness. The main subject of this paper focuses on the experimental research management applied to a technological process whose final purpose was to determine an equation of the surface roughness depending on the process parameters, obtained by the Al7136 end milling process. The research method used in this paper is the Taguchi's method. According to the research management steps, in order to perform the experimental determination of the surface roughness, an experimental stand used to determine the objective function was presented. The surface roughness equat…
The principal as a key actor in promoting teachers’ innovativeness – analyzing the innovativeness of teaching staff with variance-based partial least…
2018
The study examines the correlation between collective innovativeness of the teaching staff and the principal’s leadership style as well as additional school structure characteristics. The construct...
Análisis de métodos de validación cruzada para la obtención robusta de parámetros biofísicos
2015
[EN] Non-parametric regression methods are powerful statistical methods to retrieve biophysical parameters from remote sensing measurements. However, their performance can be affected by what has been presented during the training phase. To ensure robust retrievals, various cross-validation sub-sampling methods are often used, which allow to evaluate the model with subsets of the field dataset. Here, two types of cross-validation techniques were analyzed in the development of non-parametric regression models: hold-out and k-fold. Selected non-parametric linear regression methods were least squares Linear Regression (LR) and Partial Least Squares Regression (PLSR), and nonlinear methods were…
Analysis of the Russian and World Marker of Telemedicine and Biochipping: Features and Development Prospects
2019
The paper considers the telemedicine and biochipping market and studies the peculiarities of its development and problems in different countries. The purpose is to study the experience of telemedicine and biochipping in the world, and its features and prospects of development. The authors used methods of generalization, comparison, sampling, regression analysis, scientific articles and expert opinions to make a comparative analysis of the experience and results of the implementation of biochipping and telemedicine. The following conclusion was made: with the introduction of biochipping, the problem of a large number of long-term hospital and false ambulance calls will be solved, and the bod…