Search results for "multivariate statistics"

Psychosocial and environmental correlates of active commuting for university students.

2009

Abstract Objective To examine psychosocial and environmental correlates of active commuting to university (ACU) and explore its association with overall physical activity among college students. Methods The sample included 518 students (mean 22.4 years; 59.7% female) from two universities in Valencia, Spain. Weekly estimations of energy expenditure from ACU and total physical activity were obtained. Socio-economic status, self-efficacy, barriers to active transport, access to car and motorbike, access to public transport, walking and cycling facilities and distance to university were assessed. Data were collected April and May of 2009, using a self-administered survey. A structural equation…

Entrepreneurial success and human resources

2011

PurposeThis paper aims to determine factors that have an influence on human resource management and entrepreneurial success in the context of European innovative small and medium‐sized enterprises (SMEs).Design/methodology/approachA primary test questionnaire was tested with 50 Spanish entrepreneurs. The feedback from this study was used to improve the survey for a final test. Multivariate regression analysis was used to differentiate the factors that allow the explanation of the variables to be studied and factors that, a priori, seem to be the most relevant in explaining entrepreneurial success.FindingsThe study allows the determination of what factors make the European entrepreneur succe…

Multivariate Methods Based Soft Measurement for Wine Quality Evaluation

2014

Published version of an article in the journal: Abstract and Applied Analysis. Also available from the publisher at: http://dx.doi.org/10.1155/2014/740754 Open Access Soft measurement is a new, developing, and promising industry technology and has been widely used in the industry nowadays. This technology plays a significant role especially in the case where some key variables are difficult to be measured by traditional measurement methods. In this paper, the quality of the wine is evaluated given the wine physicochemical indexes according to multivariate methods based soft measurement. The multivariate methods used in this paper include ordinary least squares regression (OLSR), principal c…

Terahertz Biomedical Imaging: From Multivariate Analysis and Detection to Material Parameter Extraction

2017

Terahertz imaging is an interesting route for biomedical analysis. In particular, cancer imaging is a subject of study for different teams [1,2]. A work is done in Bordeaux in partnership with a hospital to do terahertz analysis of breast tissue. This work is done in reflection with time domain imaging setup with fresh samples. The aim is to accurately assess tumor margins and which could in the future allow a quick validation of the precision of the surgical procedure and know if new surgery should be performed. We have presented in a previous paper [3] the use of automatic methods of image generation with different parameters [4] in order to explore the different contrasts that exist in t…

Multivariate approaches to behavioral physiology

2017

A multivariate approach of the factors impacting a small arctic glacier, Austre Lovén-Spitsberg

2015

International audience; Arctic glaciers are good indicators of the ongoing climate change as their dynamics are strongly linked to it. This study is focused on the Austre Lovén glacier, on the Brøgger peninsula in Spitsbergen (Svalbard, 79°N). The aim is to understand how contrasted climate and snow conditions over the course of a year can lead to multiple consequences, sometimes unexpected, on mass balance. In 2014, a negative budget was expected, but data analysis has shown the first positive mass balance in 7 years. The objective here is to (i) identify and qualify the combination of factors affecting an arctic glacier mass balance. Three primary indicators seem to display the greatest i…

Évaluation de l'influence des facteurs climatiques sur le bilan de masse du glacier Austre Loven (Spitsberg, 79°N) par une approche multivariée

2016

Arctic is a region where a quick warming is ongoing. Effects are particularly visible on glaciers of which dynamics is very sensitive to climate change. The goal of this study is to identify and rank the main climatological and nivological factors influencing the mass balance of a small arctic glacier in Svalbard using a statistical approach. To highlight spatial differences, cartography were then used. Results show that positive degree-days play an important role in explaining mass balance contrary to liquid precipitations that had a marginal effect over the studied period (2007-2014). Moreover, years with very different climatic conditions can lead to a similar mass balance.

Microstructural assessment of rodent behavior in the hole-board experimental assay

2010

The aim of the present methodological article was to assess whether a microstructure of hole-exploratory activity can be demonstrated in rats tested in the hole-board, an experimental assay widely used to study anxiety-related behaviors in rodents. Six never properly described hole exploratory behavioral components were identified: active-dip, static-dip, rapid-dip, circular-sniff, point-sniff and central-sniff. Results, assessed by means of descriptive and multivariate approaches, reveal a complex microstructural organization of these behavioral elements. The hypothesis of an important role of the relationships between point-sniff and head dipping activities, in anxiety-related hole explor…

On the calculation of derived variables in the analysis of multivariate responses

1992

AbstractThe multivariate regression of a p × 1 vector Y of random variables on a q × 1 vector X of explanatory variables is considered. It is assumed that linear transformations of the components of Y can be the basis for useful interpretation whereas the components of X have strong individual identity. When p ≥ q a transformation is found to a new q × 1 vector of responses Y∗ such that in the multiple regression of, say, Y1∗ on X, only the coefficient of X1 is nonzero, i.e. such that Y1∗ is conditionally independent of X2, …, Xq, given X1. Some associated inferential procedures are sketched. An illustrative example is described in which the resulting transformation has aided interpretation.

Cognitive and neuropsychological profiles of the elderly

1993

Testing the cognitive functions of the elderly is often eclectic and atheoretical. We take a theoretical model, simultaneous and successive processing, and the tests derived from it to describe the cognitive functions of the elderly. Subsequently, the performance of an elderly sample on a battery of neuropsychological tests is examined and also understood in relation to the two processing modes. Subjects were 81 individuals, 75 years old, from a population of nearly 300 persons participating in a Finnish research project on aging. They were administered tests of simultaneous and successive processing as well as an extensive battery of neuropsychological tasks. Multivariate and univariate an…