Search results for "regression"
showing 10 items of 2619 documents
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…
Reliability of Short-Term Heart Rate Variability Indexes Assessed through Photoplethysmography
2018
The gold standard method to monitor heart rate variability (HRV) comprises measuring the time series of interbeat interval durations from electrocardiographic (ECG) recordings. However, due to the widespread use, simplicity and usability of photoplethysmographic (PPG) techniques, monitoring pulse rate variability (PRV) from pulse wave recordings has become a viable alternative to standard HRV analysis. The present study investigates the accuracy of PRV, measured as a surrogate of HRV, for the quantification of descriptive indexes computed in the time domain (mean, variance), frequency domain (low-to-high frequency power ratio LF/HF, HF band central frequency) and information domain (entropy…
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…
Retrieval of oceanic chlorophyll concentration with relevance vector machines
2006
Abstract In this communication, we evaluate the performance of the relevance vector machine (RVM) for the estimation of biophysical parameters from remote sensing data. For illustration purposes, we focus on the estimation of chlorophyll-a concentrations from remote sensing reflectance just above the ocean surface. A variety of bio-optical algorithms have been developed to relate measurements of ocean radiance to in situ concentrations of phytoplankton pigments, and ultimately most of these algorithms demonstrate the potential of quantifying chlorophyll-a concentrations accurately from multispectral satellite ocean color data. Both satellite-derived data and in situ measurements are subject…
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 …
Relationship Between Extreme Rainfall and Surface Temperature in Sicily (Italy)
2018
The study of the relationship between extreme rainfall events and surface temperature represents an important issue in hydrology and meteorology and it could be of capital importance for evaluating the effect of global warming on future precipitation. Various approaches have been tested across different parts of the world, and, in many cases, it has been observed an intensification of precipitation with increasing temperature consistently with the thermodynamic Clausius-Clapeyron relation (CC-rate of 6-7% °C-1), according to which a warmer atmosphere is capable of holding more moisture. Nevertheless, in different locations, the scaling rate between temperature and extreme precipitation has …
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…
Modelling the timing of divorce in Italy: a survival analysis on regression quantiles
2011
The analysis of marital dissolution in Italy represents a quite interesting and challenging topic from a substantive standpoint; in fact, despite of the decreasing number of marriages and the increasing number of divorces, the traditional family based on the marriage of heterosexual partners is still considered as a fundamental institution of the society. Here we present a censored quantile regression model with additive terms to investigate the determinants of the timing of marital dissolution on a large and substantial sample from a survey carried on in Italy.
The oceanic state: a conceptual elucidation in terms of modal contact
2012
Despite its lengthy history in psychoanalysis, the psychological origins, essential features and value of the oceanic state remain open to dispute. This ambiguity has come at a cost to the clarity of theoretical discussions on the topic. In working towards a conceptual elucidation, the author maintains that there are three primary accounts of the oceanic state: the metaphysical one of Romain Rolland, the developmental one of Sigmund Freud, and the cognitive-perceptual one of Anton Ehrenzweig. Based on the notion of modal contact, he argues that the accounts share a general theoretical structure that establishes as the necessary criterion for all oceanic states the loosening of ego boundarie…