Search results for "Clusterin"
showing 10 items of 478 documents
Clustering of textual networks: analysing open-ended questions in text data of the perception of minerality in wine
2014
International audience; Open-ended questions are commonly used in sensory analyses, and are usually dealt with by correspondence analysis (CA) of the term-respondent matrix. CA is apt in detecting strong associations between terms and groups of respondents, but less so when the questions are interpreted differently among respondents and, thus, seem to open a polysemic space for the answers. Also, CA offers little flexibility in filtering out irrelevant textual structure, or in controlling the relative contribution of rare versus frequent terms in the overall analysis. This contribution presents methodological extensions of CA together with application on a survey of 1900 responses bearing u…
Genes, Ageing and Longevity in Humans: Problems, Advantages and Perspectives.
2006
Many epidemiological data indicate the presence of a strong familial component of longevity that is largely determined by genetics, and a number of possible associations between longevity and allelic variants of genes have been described. A breakthrough strategy to get insight into the genetics of longevity is the study of centenarians, the best example of successful ageing. We review the main results regarding nuclear genes as well as the mitochondrial genome, focusing on the investigations performed on Italian centenarians, compared to those from other countries. These studies produced interesting results on many putative "longevity genes". Nevertheless, many discrepancies are reported, l…
A 3-D marker-free system for the analysis of movement disabilities--an application to the legs.
2001
The aim of this paper is to describe an approach allowing the analysis of human motion in three-dimensional (3-D) space. The system that we developed is composed of three charge-coupled-device cameras that capture synchronized image sequences of a human body in motion without the use of markers. Characteristic points belonging to the boundaries of the body in motion are first extracted from the initial images. Two-dimensional superquadrics are then adjusted on these points by a fuzzy clustering process. After that, the position of a 3-D model based on a set of articulated superquadrics, each of them describing a part of the human body, is reconstructed. An optical flow process allows the pr…
Clustering ball possession duration according to players’ role in football small-sided games
2022
This study aimed to explore which offensive variables best discriminate the ball possession duration according to players specific role (defenders, midfielders, attackers) during a Gk+3vs3+Gk football small-sided games. Fifteen under-15 players (age 13.2±1.0 years, playing experience 4.2±1.0 years) were grouped according to their positions (team of defenders, n = 5; team of midfielders, n = 7; team of attackers, n = 3). On each testing day (n = 3), each team performed one bout of 5-min against each team in a random order, accounting for a total of nine bouts in the following scenarios: i) defenders vs midfielders; ii) defenders vs attackers; iii) midfielders vs attackers. Based on video, a …
Non-Hierarchical Clustering as a method to analyse an open-ended questionnaire on algebraic thinking
2016
The problem of taking a data set and separating it into subgroups, where the members of each subgroup are more similar to each other than they are to members outside the subgroup, has been extensively studied in science and mathematics education research. Student responses to written questions and multiple-choice tests have been characterised and studied using several qualitative and/or quantitative analysis methods. However, there are inherent difficulties in the categorisation of student responses in the case of open-ended questionnaires. Very often, researcher bias means that the categories picked out tend to find the groups of students that the researcher is seeking out. In this paper, …
Modelling systemic price cojumps with Hawkes factor models
2015
Instabilities in the price dynamics of a large number of financial assets are a clear sign of systemic events. By investigating a set of 20 high cap stocks traded at the Italian Stock Exchange, we find that there is a large number of high frequency cojumps. We show that the dynamics of these jumps is described neither by a multivariate Poisson nor by a multivariate Hawkes model. We introduce a Hawkes one factor model which is able to capture simultaneously the time clustering of jumps and the high synchronization of jumps across assets.
Mercury$$^\mathrm{\textregistered }$$: A Software Based on Fuzzy Clustering for Computer-Assisted Composition
2019
We present Mercury, a new software for computer-assisted composition based on fuzzy clustering algorithms. This software is able to generate a big number of transitions between any two different melodies, harmonic progressions or rhythmical patterns. Mercury works with symbolic music notation. The software is, therefore, able to read music and to export the generated musical production into MusicXML format. This paper focusses on some theoretical aspects of the CFT algorithm implemented in the software in order to create those complete transitions, overviewing not only the structure of the program but the user’s interface and its music notation module. Finally, the wide variety of compositi…
Clustering-Based Algorithm for Connectivity Maintenance in Vehicular Ad-Hoc Networks
2014
International audience; Among recent advances in wireless communication technologies' field, Vehicular Ad-hoc Networks (VANETs) have drawn the attention of both academic and industry researchers due to their potential applications including driving safety, entertainment, emergency applications, and content sharing. VANET networks are characterized by their high mobile topology changes. Clustering is one of the control schemes used to make this global topology less dynamic. It allows the formation of dynamic virtual backbone used to organize the medium access, to support quality of service and to simplify routing. Mainly, nodes are organized into clusters with at least one cluster head (CH) …
ASSESSING NEIGHBORHOOD DISORDER: VALIDATION OF A THREE-FACTOR OBSERVATIONAL SCALE
2015
AbstractThis study presents data on the development and preliminary validation of an observational scale assessing neighborhood disorder. Independent observations by trained raters of neighborhood disorder were conducted in 552 census block groups in the city of Valencia (Spain). Intraclass correlation coefficients assessing inter-rater reliability indicated fair to substantial levels of agreement among raters. Confirmatory factor analyses supported a final three-factor model scale measuring physical disorder, social disorder, and physical decay. Results for the internal consistency showed large composite reliability indices indicating good reliability for all neighborhood disorder factors.…
Evaluación del desorden en los vecindarios: validación de una escala observacional de tres factores
2015
This study presents data on the development and preliminary validation of an observational scale assessing neighborhood disorder. Independent observations by trained raters of neighborhood disorder were conducted in 552 census block groups in the city of Valencia (Spain). Intraclass correlation coefficients assessing inter-rater reliability indicated fair to substantial levels of agreement among raters. Confirmatory factor analyses supported a final three-factor model scale measuring physical disorder, social disorder, and physical decay. Results for the internal consistency showed large composite reliability indices indicating good reliability for all neighborhood disorder factors. Evidenc…