Purificación Galindo Villardón
University of Salamanca, Statistics, Faculty Member
Since 2002 many works have been published applying Principal Component Analysis (PCA) in the study of network traffic. These investigations have revealed some issues inherent to the temporal and spatial correlations present in the data,... more
Since 2002 many works have been published applying Principal Component Analysis (PCA) in the study of network traffic. These investigations have revealed some issues inherent to the temporal and spatial correlations present in the data, which are not considered in PCA. The proposed solutions to these problems include the formulation of a new matrix of data “rearranged” to take these effects into consideration. Nevertheless the “classical” Biplot methods (GH, JK, HJ) reflect both correlations between time intervals and between time series. The Biplot methods provide graphical procedures that offer more information about the behavior of time series than PCA, while making possible the use of more specific quality of representation metrics. In the case of HJ-Biplot, the graphical display obtained has maximum quality of representation for rows and columns.
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Meta-Biplot as a measure of social protection variables for European and Latin American countries. Within the framework of Social Security, pension systems are a social protection mechanism whose purpose is to provide income to people who... more
Meta-Biplot as a measure of social protection variables for European and Latin American countries. Within the framework of Social Security, pension systems are a social protection mechanism whose purpose is to provide income to people who lose their self-generating capacity due to old age (old-age rights and benefits), disability (disability rights and benefits), or death of one of the primary sources of income of a family (survivors ’ rights and benefits). Social protection systems occupy a prominent place in the Sustainable Development Goals (SDGs) of the United Nations, which is reflected in its goal 1.3, where it is urged to implement social protection systems and increment the coverage of the vulnerable population. In terms of social security, European countries have the most experience. Latin America has been one of the forerunners in introducing individual capitalization schemes as a mandatory component in its pension systems for more than 30 years. When Chile abandoned its p...
International rankings have achieved great prestige as an instrument for measuring university excellence as a quality assurance mechanism. Thus, this research aims to observe the behavior of the best-positioned universities in these... more
International rankings have achieved great prestige as an instrument for measuring university excellence as a quality assurance mechanism. Thus, this research aims to observe the behavior of the best-positioned universities in these rankings, as well as the trajectories of indicators and institutions. In fact, the Top-15 universities of ARWU, THE, and QS were selected, and an analysis was carried out using the Dynamic Biplot technique, which allows the study of the relationship between a set of multivariate data developed on more than one occasion. The results prove that world-class universities show different characteristics and trajectories when analyzed multivariate and dynamically. The ranking indicators also reveal different correlations that may affect the final ranking.
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Corporate Social Responsibility (CSR) has the characteristic of being a truly global idea, and its global features could give rise to the assumption that national dynamics are secondary or even irrelevant. However, while CSR policies may... more
Corporate Social Responsibility (CSR) has the characteristic of being a truly global idea, and its global features could give rise to the assumption that national dynamics are secondary or even irrelevant. However, while CSR policies may be of a global nature, recent research suggests that lasting national institutions and distinctive ideological traditions determine corporate decisions. In this study, we analysed the 2004–2014 decade from a panel data sample of 6600 observations from 600 large, internationally listed companies, and based on multivariate statistical methods, we contrasted the relevance of national identity in the sustainable behaviour of companies with the discovery of important national discrepancies, which corroborates that the country of origin of companies offers a series of facilities and barriers for the development of CSR practices. Companies, depending on different pressures and expectations, care about what is important in their own country. Thus, the corpo...
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Localización: Innovation and multidimensional entrepreneurship: economic, social and academic aspects: revised papers presented at the 13th Uddevalla Symposium, 19-22 august 2010, Jönköping, Sweden/coord. por Iréne Bernhard, 2011, ISBN... more
Localización: Innovation and multidimensional entrepreneurship: economic, social and academic aspects: revised papers presented at the 13th Uddevalla Symposium, 19-22 august 2010, Jönköping, Sweden/coord. por Iréne Bernhard, 2011, ISBN 978-91-633-...
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With the growth of cities, urban traffic has increased and traffic congestion has become a serious problem. Due to their characteristics, metro systems are one of the most used public transportation networks in big cities. So,... more
With the growth of cities, urban traffic has increased and traffic congestion has become a serious problem. Due to their characteristics, metro systems are one of the most used public transportation networks in big cities. So, optimization and planning of metro networks are challenges which governments must focus on. The objective of this study was to analyze Madrid metro network using graph theory. Through complex network theory, the main structural and topological properties of the network as well as robustness characteristics were obtained. Furthermore, to inspect these results, multivariate analysis techniques were employed, specifically HJ-Biplot. This analysis tool allowed us to explore relationships between centrality measures and to classify stations according to their centrality. Therefore, it is a multidisciplinary study that includes network analysis and multivariate analysis. The study found that closeness and eccentricity were strongly negatively correlated. In addition...
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The present article offers a concise theoretical conceptualization and operational analysis of the contribution of innovation to regional development. The latter concepts are closely related to geographical proximity, knowledge diffusion... more
The present article offers a concise theoretical conceptualization and operational analysis of the contribution of innovation to regional development. The latter concepts are closely related to geographical proximity, knowledge diffusion and filters and clustering. Institutional innovation profiles and regional patterns of innovation are two mutually linked, novel conceptual elements in this article. Next to a theoretical framing, the article employs the regional innovation systems concept as a vehicle to analyse institutional innovation profiles. Our case study addresses three Portuguese regions and their institutions, included in a web-based inventory of innovation agencies which offered the foundation for an extensive database. This data-set was analysed by means of a recently developed principal coordinates analysis followed by a Logistic Biplot approach (leading to a Voronoi mapping) to design a systemic typology of innovation structures where each institution is individually r...
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This quantitative study used descriptive and correlational designs, together with Biplot methods, to determine variables that influence security in schools, the relationship between them, and the formation of clusters. The results showed... more
This quantitative study used descriptive and correlational designs, together with Biplot methods, to determine variables that influence security in schools, the relationship between them, and the formation of clusters. The results showed differences among schools according to location, in reference to the variables that influence security. On the contrary, there were no differences in relation to the acts that threaten school security; generally, they occur occasionally. On the other hand, a negative correlation was found between parents’ participation at school, security services, security measures with students, and drug control practices. The relationships between these variables and others contributed to the formation of schools clusters. Implications and suggestions for future research are discussed in terms of school security. How to cite: Vázquez-Pérez, J. P., Vicente-Galindo, P., & Galindo-Villardón, M. P. (2011). Variables que inciden en la seguridad de las escuelas públicas de los Estados Unidos. Pedagogía, 44(1), 141-165. Retrieved https://revistas.upr.edu/index.php/educacion/article/view/16565Esta investigación cuantitativa utilizó los diseños descriptivo y correlacional, junto con los métodos Biplot, para determinar variables que incidían en la seguridad escolar, las relaciones existentes entre ellas y la formación de conglomerados. En los resultados, se demostró que, según la ubicación de las escuelas, las variables que incidieron en la seguridad son diferentes. Por el contrario, con respecto a los actos que atentan contra la seguridad, no se observaron diferencias por ubicación; en general, en todas ocurrían ocasionalmente. Por otro lado, se encontró una correlación negativa entre la participación de los padres, los servicios de seguridad, las medidas de seguridad con los estudiantes y las prácticas antidrogas. Las relaciones entre estas y otras variables contribuyeron a la formación de conglomerados entre las escuelas. Las implicaciones y recomendaciones para futuras investigaciones se presentan en términos de la seguridad escolar. Cómo citar: Vázquez-Pérez, J. P., Vicente-Galindo, P., & Galindo-Villardón, M. P. (2011). Variables que inciden en la seguridad de las escuelas públicas de los Estados Unidos. Pedagogía, 44(1), 141-165. Recuperado a partir de https://revistas.upr.edu/index.php/educacion/article/view/1656
The texts of the various papers in this volume were set individually by the authors or under their supervisión. Only minor corrections to the text have been carried out by the editors. No Responsability is assumed by the Publisher, the... more
The texts of the various papers in this volume were set individually by the authors or under their supervisión. Only minor corrections to the text have been carried out by the editors. No Responsability is assumed by the Publisher, the Editors and the Authors for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use of operation of any methods, products, instructions or ideas contained in the material herein. © Statistics Department All rights reserved. No part of this publication may be reproduced, stored in retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior writen permission of the Editors.
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PRIME has been between 2000 and 2006 a commonly used public policy instrument. Although nationally promoted, it served the diffusion of European funds across the entrepreneurial tissue. In this paper we intend to follow the application of... more
PRIME has been between 2000 and 2006 a commonly used public policy instrument. Although nationally promoted, it served the diffusion of European funds across the entrepreneurial tissue. In this paper we intend to follow the application of this instrument for a monitoring and strategic evaluation of policy support system to companies’; in particularly, the analyses at regional scale can identify some eventual hindrances to success. Methodologically, we have observed the financing execution of 14910 projects, collected from the official information portal of PRIME in Portugal. Due to limitations related to the information sources of the portal our study deals with a reduced number of variables: project location, year, industrial activity, financial program, NUT, district, investment and incentive. Nevertheless, the application of HOMALS, Cluster and Correspondence Analyses was possible, allowing conclusions about the level of effectiveness of PRIME across, both, location and sectors l...
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Tomato (Solanum lycopersicum Mill) is an important crop in terms of its economic and nutritional value. Many factors, including cultivar, climate, geography, geochemistry, and agricultural practice, can affect its nutrient concentrations.... more
Tomato (Solanum lycopersicum Mill) is an important crop in terms of its economic and nutritional value. Many factors, including cultivar, climate, geography, geochemistry, and agricultural practice, can affect its nutrient concentrations. An HJ‐biplot study was performed to examine the effects of cultivar (Dorothy, Boludo, Dominique, Thomas, and Dunkan), agricultural practices, climatic factors, and their interactions. Significant differences were analyzed using a one‐way ANOVA. All samples were collected and assayed at the same degree of ripeness. In the conventional and organic tomato samples, those harvested from December to April had the highest concentrations of fructose, glucose, citric acid, malic acid, ascorbic acid, protein, Na, and Mg, while those harvested in October had the highest concentrations of lycopene and hydroxycinnamic acid. There were high concentrations of Ca, P, Zn, and Cu in the no‐soil tomatoes. Conventional and organic cultivation practices showed similar ...
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The strategic choices regarding innovation and research and development (R&D) policy in Portugal have, over the past two decades, produced various positive benefits, in which the regions of Lisbon and Algarve, in particular, have taken... more
The strategic choices regarding innovation and research and development (R&D) policy in Portugal have, over the past two decades, produced various positive benefits, in which the regions of Lisbon and Algarve, in particular, have taken the lead. These are the only regions in Portugal which converge towards the European average growth rate with respect to gross production, investment and employment creation. It is now timely to evaluate firms’ contributions to national and regional growth, their obstacles, and impacts. After a conceptualization of innovation policy in Portugal, the present paper treats innovation as a major criterion for the policy evaluation process referred to above. Our empirical investigation aims to explain the innovation performance of Portuguese firms throughout the country, and to explore those determinants of innovation which are region-specific. Therefore, the analysis addresses a set of firms’ achievement patterns, by focusing on ways in which institutions...
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Research Interests: Pathology, Incidence Geometry, Biology, Medicine, Humans, and 15 moreChronic Lymphocytic Leukemia, Case Study, Female, Male, Bone marrow, Aged, Middle Aged, Multiple regression analysis, B Lymphocytes, Lymphocytosis, Chronic Lymphocytic Leukaemia, Neoplasm staging, Cardiovascular medicine and haematology, B cell, and Blut
Frecuentemente encontramos que para demostrar la validez de una estructura factorial, previamente identificada en un Analisis Factorial Exploratorio, y por tanto la validez de las deducciones teoricas inferidas del mismo, se utilice un... more
Frecuentemente encontramos que para demostrar la validez de una estructura factorial, previamente identificada en un Analisis Factorial Exploratorio, y por tanto la validez de las deducciones teoricas inferidas del mismo, se utilice un Analisis Factorial Confirmatorio. En este trabajo utilizaremos esa estrategia para estudiar la validez del cuestionario de Salud General (GHQ-28); una prueba disenada para medir trastornos psiquiatricos no psicoticos en contextos comunitarios y ocupacionales. El colectivo estudiado es la Plantilla de Profesores a Tiempo Completo de la Universidad de Salamanca.
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Este Libro de Actas recoge los resumenes de los trabajos presentados, en Junio de 2007, por más de 800 investigadores de todo el mundo. Más de 100 Posters, 22 sesiones de Comunicaciones orales, más de 150 Ponencias, 6 Simposios y 8... more
Este Libro de Actas recoge los resumenes de los trabajos presentados, en Junio de 2007, por más de 800 investigadores de todo el mundo. Más de 100 Posters, 22 sesiones de Comunicaciones orales, más de 150 Ponencias, 6 Simposios y 8 Conferencias Plenarias. Las Conferencias plenarias versaron sobre: Inferencia mediante Remuestreo (J.L. Chorro); Tests de Bioequivalencia y de No-Inferioridad con dos proporciones (A. Martín Andres); Modelos aumentados en ceros en biodiversidad aplicada (L. Pla); Parametric Dynamic Correspondence Analysis (C. Cuadras); La Modelización Estadística ( M.M. Ojeda); Formal and Informal Model Selection and Assessment when data are incomplite (G. Molemberghs); Experimental Design and Analysis for large microarray experiments (A. Mead); Realidad a la Medida (F. Mallo) Los Simposios versaron sobre: Métodos Biométricos Avanzados en la Investigación; Médica Básica y Aplicada; Bioincertidumbre en Salud Laboral; Aplicaciones Psicométricas; Medición de Variables Psicol...
The scientific literature is abundant regarding control charts in multivariate environments for numerical and mixed data; however, there are few publications for qualitative data. Qualitative variables provide valuable information on... more
The scientific literature is abundant regarding control charts in multivariate environments for numerical and mixed data; however, there are few publications for qualitative data. Qualitative variables provide valuable information on processes in various industrial, productive, technological, and health contexts. Social processes are no exception. There are multiple nominal and ordinal categorical variables used in economics, psychology, law, sociology, and education, whose analysis adds value to decision-making; therefore, their representation in control charts would be useful. When there are many variables, there is a risk of redundant or excessive information, so the application of multivariate methods for dimension reduction to retain a few latent variables, i.e., a recombination of the original and synthesizing of most of the information, is viable. In this context, the T2Qv control chart is presented as a multivariate statistical process control technique that performs an anal...
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Cardiotoxicity due to anthracyclines (CDA) affects cancer patients, but we cannot predict who may suffer from this complication. CDA is a complex disease whose polygenic component is mainly unidentified. We propose that levels of... more
Cardiotoxicity due to anthracyclines (CDA) affects cancer patients, but we cannot predict who may suffer from this complication. CDA is a complex disease whose polygenic component is mainly unidentified. We propose that levels of intermediate molecular phenotypes in the myocardium associated with histopathological damage could explain CDA susceptibility; so that variants of genes encoding these intermediate molecular phenotypes could identify patients susceptible to this complication. A genetically heterogeneous cohort of mice generated by backcrossing (N = 165) was treated with doxorubicin and docetaxel. Cardiac histopathological damage was measured by fibrosis and cardiomyocyte size by an Ariol slide scanner. We determine intramyocardial levels of intermediate molecular phenotypes of CDA associated with histopathological damage and quantitative trait loci (ipQTLs) linked to them. These ipQTLs seem to contribute to the missing heritability of CDA because they improve the heritabili...
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Cocoa is the main crop in Ecuador’s agricultural sector and is the most important to the country’s economy. This crop is mainly threatened by moniliasis caused by Moniliophthora roreri and Moniliophthora perniciosa. Monialisis is a... more
Cocoa is the main crop in Ecuador’s agricultural sector and is the most important to the country’s economy. This crop is mainly threatened by moniliasis caused by Moniliophthora roreri and Moniliophthora perniciosa. Monialisis is a disease that causes the watery rot of cocoa beans, causing serious yield losses at crop harvest and great economic losses. In this research, we used 50 Trichoderma spp. cultivated in two culture media, PDA and MEA, to demonstrate mycelial growth and antagonistic capacity against two cacao-crop pathogens: M. roreri and M. perniciosa. Multivariate methods, namely a PCA biplot and a GGE biplot, indicated that four strains of Trichoderma spp. (17, 33, 42 and 44) cultivated on the PDA medium had the highest mycelial characteristic values and antagonistic capacities against Moniliophthora perniciosa. The experimental test showed that the lowest incidence of moniliasis and highest yield of cocoa occurred when using the treatments based on the Trichoderma spp. Th...
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Resumen En este trabajo proponemos dos soluciones al problema que se plantea cuando se pretende analizar datos multivariantes, para un conjunto de individuos con estructura de grupos, que además han sido replicados bien sea en ocasiones o... more
Resumen En este trabajo proponemos dos soluciones al problema que se plantea cuando se pretende analizar datos multivariantes, para un conjunto de individuos con estructura de grupos, que además han sido replicados bien sea en ocasiones o en situaciones ...
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En este trabajo se presentan los resultados de un estudio, el primero de estas características a nivel de la Comunidad de Castilla y León, cuyo objetivo es identificar los perfiles socioeconómicos de las mujeres salmantinas, en situación... more
En este trabajo se presentan los resultados de un estudio, el primero de estas características a nivel de la Comunidad de Castilla y León, cuyo objetivo es identificar los perfiles socioeconómicos de las mujeres salmantinas, en situación de irregularidad laboral, en comparación con las características de las mujeres que desarrollan su actividad en un marco laboral regular.<br /><br />The objective of this work is identifying the socio-economic profiles of women holding undeclared jobs as opposed to the profites of those holding declared jobs. This study is the first of its kind in the Castilla y León Community.
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In this research, a dataset of growth performances and nutritional composition of juvenile Litopenaeus vannamei after being fed two diets that include aquaculture binder with sardine for 7 weeks was analyzed using data mining techniques:... more
In this research, a dataset of growth performances and nutritional composition of juvenile Litopenaeus vannamei after being fed two diets that include aquaculture binder with sardine for 7 weeks was analyzed using data mining techniques: the K-Means Clustering Algorithm and PCA Biplot, to have a visualization of each parameter (vector) measured. The parameters evaluated were: weight gain, specific growth rate, feed efficiency, protein efficiency ratio, survival percent, moisture content, crude protein, crude lipid, and ash content. Data mining tools showed the juvenile Litopenaeus vannamei fed with mixture 2 (pellets mixed with the binder of sardine subproducts) presented the highest growth performances and nutritional composition, 23 juvenile L. vannamei shrimps showed higher relation with crude protein and crude lipid, 30 L. vannamei shrimps presented higher relation with ash, and 37 juvenile L. vannamei shrimps showed higher relation with ash and moisture. The results obtained in...
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[ENG]The JK’ Biplot technique as used for an initial research about the dynamic of biochemical parameters in three representative forest of the Sierra de Francia area, Salamanca province (Spain). This initial approximation indicate that... more
[ENG]The JK’ Biplot technique as used for an initial research about the dynamic of biochemical parameters in three representative forest of the Sierra de Francia area, Salamanca province (Spain). This initial approximation indicate that soil parameters in Chesnut (wood) were different from the others two stands.10261/2990
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Usually, psychometricians apply classical factorial analysis to evaluate construct validity of order rankscales. Nevertheless, these scales have particular characteristics that must be taken into account: totalscores and rank are highly... more
Usually, psychometricians apply classical factorial analysis to evaluate construct validity of order rankscales. Nevertheless, these scales have particular characteristics that must be taken into account: totalscores and rank are highly relevant. Geologische Vereinigung; Universitat de Barcelona, Equip de Recerca Arqueomètrica; Institut d’Estadística de Catalunya; International Association for Mathematical Geology; Patronat de l’Escola Politècnica Superior de la Universitat de Girona; Fundació privada: Girona, Universitat i Futur.
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Multicollinearity generates imprecision in the estimates of the coefficients in linear models. We propose to use the h-plot of the inverse of the correlation matrix to obtain a representation of the linear relations between the predictor... more
Multicollinearity generates imprecision in the estimates of the coefficients in linear models. We propose to use the h-plot of the inverse of the correlation matrix to obtain a representation of the linear relations between the predictor variables. In the resulting plot the variance ...