A study of data analysis techniques. Application to personal data analysis in the context of social networks

En los últimos años la sociedad está experimentando una serie de cambios. Uno de estos cambios es la datificación (“datafication” en inglés). Este término puede ser definido como la transformación sistemática de aspectos de la vida cotidiana de las personas en datos procesados por ordenadores. Cada día, a cada minuto y a cada segundo, cada vez que alguien emplea un dispositivo digital,hay datos siendo guardados en algún lugar. Se puede tratar del contenido de un correo electrónico pero también puede ser el número de pasos que esa persona ha caminado o su historial médico. El simple almacenamiento de datos no proporciona un valor añadido por si solo. Para extraer conocimiento de los datos, y por tanto darles un valor, se requiere del análisis de datos. La ciencia de los datos junto con el análisis de datos se está volviendo cada vez más popular. Hoy en día, se pueden encontrar millones de web APIs estadísticas; estas APIs ofrecen la posibilidad de analizar tendencias o sentimientos presentes en las redes sociales o en internet en general. Una de las redes sociales más populares, Twitter, es pública. Cada mensaje, o tweet, publicado puede ser visto por cualquier persona en el mundo, siempre y cuando posea una conexión a internet. Esto hace de Twitter un medio interesante a la hora de analizar hábitos sociales o perfiles de consumo. Es en este contexto en que se engloba este proyecto. Este trabajo, combinando el análisis estadístico de datos y el análisis de contenido, trata de extraer conocimiento de tweets públicos de Twitter. En particular tratará de establecer si el género es un factor influyente en las relaciones entre usuarios de Twitter. Para ello, se analizará una base de datos que contiene casi 2.000 tweets. En primer lugar se determinará el género de los usuarios mediante web APIs. En segundo lugar se empleará el contraste de hipótesis para saber si el género influye en los usuarios a la hora de relacionarse con otros usuarios. Finalmente se construirá un modelo estadístico para predecir el comportamiento de los usuarios de Twitter en relación a su género.

Social and content hybrid image recommender system for mobile social networks

One of the advantages of social networks is the possibility to socialize and personalize the content created or shared by the users. In mobile social networks, where the devices have limited capabilities in terms of screen size and computing power, Multimedia Recommender Systems help to present the most relevant content to the users, depending on their tastes, relationships and profile. Previous recommender systems are not able to cope with the uncertainty of automated tagging and are knowledge domain dependant. In addition, the instantiation of a recommender in this domain should cope with problems arising from the collaborative filtering inherent nature (cold start, banana problem, large number of users to run, etc.). The solution presented in this paper addresses the abovementioned problems by proposing a hybrid image recommender system, which combines collaborative filtering (social techniques) with content-based techniques, leaving the user the liberty to give these processes a personal weight. It takes into account aesthetics and the formal characteristics of the images to overcome the problems of current techniques, improving the performance of existing systems to create a mobile social networks recommender with a high degree of adaptation to any kind of user.

On the localization of the personalized PageRank of complex networks

In this paper new results on personalized PageRank are shown. We consider directed graphs that may contain dangling nodes. The main result presented gives an analytical characterization of all the possible values of the personalized PageRank for any node.We use this result to give a theoretical justification of a recent model that uses the personalized PageRank to classify users of Social Networks Sites. We introduce new concepts concerning competitivity and leadership in complex networks. We also present some theoretical techniques to locate leaders and competitors which are valid for any personalization vector and by using only information related to the adjacency matrix of the graph and the distribution of its dangling nodes.

Opportunities and challenges of mobile social networks

Increasing availability (andaffordability) of mobile broadband - In 2015 half of the subscriber base will be in 3G/4G, and 80% in 2020 (27% in 2011) - 7.6 billion mobile users by 2020 (5.4 billion in 2011). Mobile subscribers per 100 inhabitants:99%. Increasing availability (and affordability) of smartphones - In 2020 81% of phones sold globally will be smartphones (2.5 billion) from 26% in 2011 (400 million) - 595 million tablets in 2020 (70 million in 2011)

Impact of new technologies and social networks on a secondary education theatre project

This paper describes the potential impact of social media and new technologies in secondary education. The case of study has been designed for the drama and theatre subject. A wide set of tools like social networks, blogs, internet, multimedia content, local press and other promotional tools are promoted to increase students’ motivation. The experiment was developed at the highschool IES Al-Satt located in Algete in the Comunidad de Madrid. The students included in the theatre group present a low academic level, 80% of them had previously repeated at least one grade, half of them come from programs for students with learning difficulties and were at risk of social exclusion. This action is supported by higher and secondary education professors and teachers who look forward to implanting networked media technologies as new tools to improve the academic results and the degree of involvement of students. The results of the experiment have been excellent, based on satisfactory opinions obtained from a survey answered by students at the end of the course, and also revealed by the analytics taken from different social networks. This project is a pioneer in the introduction and usage of new technologies in secondary high-schools in Spain.

Efficiency analysis of information technology and online social networks management : an integrated DEA-Model assessment

This paper analyses the relationship between productive efficiency and online-social-networks (OSN) in Spanish telecommunications firms. A data-envelopment-analysis (DEA) is used and several indicators of business ?social Media? activities are incorporated. A super-efficiency analysis and bootstrapping techniques are performed to increase the model?s robustness and accuracy. Then, a logistic regression model is applied to characterise factors and drivers of good performance in OSN. Results reveal the company?s ability to absorb and utilise OSNs as a key factor in improving the productive efficiency. This paper presents a model for assessing the strategic performance of the presence and activity in OSN.

Effects of inspections in small world social networks with different contagion rules

Inspections are used to prevent tax evasion or any other unlawful behavior. ? The effect of inspections depends on the network topology and the contagion rule. ? The network is modeled as a Watts?Strogatz Small World that is tuned from regular to random. ? Two contagion rules are applied: continuous and discontinuous. ? The equilibrium populations of payers and evaders are obtained in terms of these system parameters.

The anatomy of urban social networks and its implications in the searchability problem

The appearance of large geolocated communication datasets has recently increased our understanding of how social networks relate to their physical space. However, many recurrently reported properties, such as the spatial clustering of network communities, have not yet been systematically tested at different scales. In this work we analyze the social network structure of over 25 million phone users from three countries at three different scales: country, provinces and cities. We consistently find that this last urban scenario presents significant differences to common knowledge about social networks. First, the emergence of a giant component in the network seems to be controlled by whether or not the network spans over the entire urban border, almost independently of the population or geographic extension of the city. Second, urban communities are much less geographically clustered than expected. These two findings shed new light on the widely-studied searchability in self-organized networks. By exhaustive simulation of decentralized search strategies we conclude that urban networks are searchable not through geographical proximity as their country-wide counterparts, but through an homophily-driven community structure.

The Role of ICT in Scaling Up the Impact of Social Enterprises

Information and Communication Technologies (ICT) can help social enterprises and other organizations working on global sustainability issues and in the human development sector in general scale their social impact. The flexibility, dynamism, and ubiquity of ICTs make them powerful tools for improving relationships among organizations and their beneficiaries, multiplying the effects of action against many, if not all, aspects of global unsustainability, including poverty and exclusion. The scaling of social impact occurs in two different dimensions. On one hand, ICTs can increase the value proposition of a program or action (depth scaling) in different ways: providing accurate and fast needs recognition, adapting products and services, creating opportunities, building fairer markets, mobilizing actions on environmental and social issues, and creating social capital. On the other hand, ICTs can also increase the number of people reached by the organization (breadth scaling) by accessing new resources, creating synergies and networks, improving organizational efficiency, increasing its visibility, and designing new access channels to beneficiaries. This article analyzes the role of ICT in the depth and breadth scaling of social impact.

A combined algorithm for analyzing structural controllability and observability of complex networks

In this paper a combined algorithm for analyzing structural controllability and observability of complex networks is presented. The algorithm addresses the two fundamental properties to guarantee structural controllability of a system: the absence of dilations and the accessibility of all nodes. The first problem is reformulated as a Maximum Matching search and it is addressed via the Hopcroft- Karp algorithm; the second problem is solved via a new wiring algorithm. Both algorithms can be combined to efficiently determine the number of required controllers and observers as well as the new required connections in order to guarantee controllability and observability in real complex networks. An application to a Twitter social network with over 100,000 nodes illustrates the proposed algorithms.

Estudio de los principales CMS para la creación de una red social

Actualmente las redes sociales son muy utilizadas en todo el mundo, existen diferentes tipos de redes sociales con las que podemos conectar con amigos, ampliar nuestra red de contactos profesionales, aprender cosas nuevas, etc. Su elevado uso las ha convertido en uno de los negocios más rentables en internet generando fortunas para sus creadores, principalmente, a través de la publicidad. Muchas redes sociales son creadas por empresas que cuentan con un equipo experto, pero otras muchas han sido creadas por personas comunes, con bajos conocimientos informáticos, muchos motivados en sus aficiones o carreras profesionales, que al no encontrar nada en la red que les resulte útil, han decidido desarrollar ellos mismos sus propias redes sociales con la ayuda de herramientas informáticas. Una de esas herramientas son los sistemas de gestión de contenidos (CMS), con los cuales ahorraremos mucho tiempo de desarrollo y no necesitaremos invertir grandes cantidades de dinero. Este proyecto trata, principalmente, de cómo crear redes sociales haciendo uso de estas herramientas y tiene el objetivo de ser lo suficientemente claro para que cualquier persona, sin importar su nivel de conocimientos técnicos, sea capaz de desarrollar sus ideas. En la primera parte del proyecto se habla sobre las redes sociales en general y el impacto de éstas en la sociedad actual, donde se ve que, actualmente, debido a la cantidad de redes sociales y a la accesibilidad móvil, el uso de las redes sociales es una cotidianidad. También se explican algunos métodos para obtener beneficios económicos de una red social y las ventajas que presentan las redes sociales específicas frente a las generalistas, concluyendo que las redes sociales específicas van ganando mayor protagonismo con el paso del tiempo. Además, se habla sobre la crítica de las redes sociales desde el punto de vista del usuario de la red, donde se resalta el tema de la administración de la publicidad y la privatización que han supuesto las redes sociales. Posteriormente se presenta una base teórica sobre las herramientas antes mencionadas, los CMS. Se explica su funcionamiento, clasificación y las ventajas que obtenemos con el uso de este software en nuestros proyectos, de los cuales destacan el corto tiempo de desarrollo y el bajo coste. Al final se eligen los CMS de estudio en este proyecto principalmente en base a tres criterios: licencia, cuota de uso y características de red social. En la segunda parte del proyecto se habla acerca de los CMS elegidos: WordPress con su plugin BuddyPress, Elgg, y Joomla con su plugin JomSocial. Se explican las características de cada uno de ellos y se muestran ejemplos de redes sociales reales hechas con estos CMS. En esta parte del proyecto se hace un uso práctico de estos CMS y se detalla paso a paso todo el proceso de creación de una red social (instalación, configuración y personalización de la red social) para cada CMS. El resultado son tres redes sociales hechas con distintos CMS, de los cuales se hace una valoración en base a la experiencia obtenida con el uso de los mismos, concluyéndose que JomSocial es una buena opción para redes sociales de uso generalista, pero para redes específicas son mejores tanto Elgg como BuddyPress, presentando este último una ligera ventaja por tener una gran comunidad en español. ABSTRACT. Nowadays social networks are widely used throughout the world, there are different types of social networks where you can connect with friends, expand your network of professional contacts, learn new things, etc. Its high usage has turned them into one of the most profitable businesses on Internet generating fortunes to its developers, mainly through advertising. Many social networks are developed by companies that count on an expert team, but many others have been created by ordinary people, with low computer skills, many of them motivated in their hobbies or careers, that did not find anything useful on Internet and decide to develop their own social networks with the help of software tools. One of those tools is a content management system (CMS), which will help us to save a lot of development time and we will not need to invest large amounts of money. This project is, mainly, about how to create social networks using these tools and aims to be clear enough to help anyone, regardless of their computer skills, to develop their ideas. The first part of the project is about social networks in general and the impact on today's society, where we can see that, due to the number of social networks and mobile accessibility, the use of social networks is daily. Also it explains some ways to obtain economic benefits from a social network and the advantages of specific social networks against generalist social networks, concluding that specific social networks are gaining more prominence with the passage of time. In addition, it refers on social networks critique from the point of view of social network users, where it highlights the issue of the advertising administration and privatization which have brought social networks. Subsequently, it presents a theoretical base of the above mentioned tools, CMS. Explains their operation, classification and the advantages we get with the use of this software in our projects, where the short development time and lower cost are highlighted. At the end the CMS studied in this project are chosen mainly based on three criteria: license, community size and social network features. The second part of the project is about the chosen CMS: WordPress with its plugin BuddyPress, Elgg, and Joomla with its plugin JomSocial. It explains features of all of them and shows examples of real social networks developed with these CMS. This part of the project is a practical use of these CMS and detailed step by step throughout the process of creating a social network (installation, configuration and customization of the social network) for each CMS. The result are three social networks made with different CMS, from which is made an assessment on the basis of the experience gained with the use of these software, concluding that JomSocial is a good choice to develop generalist social networks, but for specific social networks are better Elgg and BuddyPress, presenting the latter a slight advantage by having a large community in Spanish.

Cognitive reserve is associated with the functional organization of brain networks in healthy aging: a MEG study

The proportion of elderly people in the population has increased rapidly in the last century and consequently "healthy aging" is expected to become a critical area of research in neuroscience. Evidence reveals how healthy aging depends on three main behavioral factors: social lifestyle, cognitive activity and physical activity. In this study, we focused on the role of cognitive activity, concentrating specifically on educational and occupational attainment factors, which were considered two of the main pillars of cognitive reserve. 21 subjects with similar rates of social lifestyle, physical and cognitive activity were selected from a sample of 55 healthy adults. These subjects were divided into two groups according to their level of cognitive reserve; one group comprised subjects with high cognitive reserve (9 members) and the other contained those with low cognitive reserve (12 members). To evaluate the cortical brain connectivity network, all participants were recorded by Magnetoencephalography (MEG) while they performed a memory task (modified version of the Sternberg¿s Task). We then applied two algorithms (Phase Locking Value & Phase-Lag Index) to study the dynamics of functional connectivity. In response to the same task, the subjects with lower cognitive reserve presented higher functional connectivity than those with higher cognitive reserve. These results may indicate that participants with low cognitive reserve needed a greater 'effort' than those with high cognitive reserve to achieve the same level of cognitive performance. Therefore, we conclude that cognitive reserve contributes to the modulation of the functional connectivity patterns of the aging brain.

Evaluation of configurations of supply networks supported by it systems

Los sistemas transaccionales tales como los programas informáticos para la planificación de recursos empresariales (ERP software) se han implementado ampliamente mientras que los sistemas analíticos para la gestión de la cadena de suministro (SCM software) no han tenido el éxito deseado por la industria de tecnología de información (TI). Aunque se documentan beneficios importantes derivados de las implantaciones de SCM software, las empresas industriales son reacias a invertir en este tipo de sistemas. Por una parte esto es debido a la falta de métodos que son capaces de detectar los beneficios por emplear esos sistemas, y por otra parte porque el coste asociado no está identificado, detallado y cuantificado suficientemente. Los esquemas de coordinación basados únicamente en sistemas ERP son alternativas válidas en la práctica industrial siempre que la relación coste-beneficio esta favorable. Por lo tanto, la evaluación de formas organizativas teniendo en cuenta explícitamente el coste debido a procesos administrativos, en particular por ciclos iterativos, es de gran interés para la toma de decisiones en el ámbito de inversiones en TI. Con el fin de cerrar la brecha, el propósito de esta investigación es proporcionar métodos de evaluación que permitan la comparación de diferentes formas de organización y niveles de soporte por sistemas informáticos. La tesis proporciona una amplia introducción, analizando los retos a los que se enfrenta la industria. Concluye con las necesidades de la industria de SCM software: unas herramientas que facilitan la evaluación integral de diferentes propuestas de organización. A continuación, la terminología clave se detalla centrándose en la teoría de la organización, las peculiaridades de inversión en TI y la tipología de software de gestión de la cadena de suministro. La revisión de la literatura clasifica las contribuciones recientes sobre la gestión de la cadena de suministro, tratando ambos conceptos, el diseño de la organización y su soporte por las TI. La clasificación incluye criterios relacionados con la metodología de la investigación y su contenido. Los estudios empíricos en el ámbito de la administración de empresas se centran en tipologías de redes industriales. Nuevos algoritmos de planificación y esquemas de coordinación innovadoras se desarrollan principalmente en el campo de la investigación de operaciones con el fin de proponer nuevas funciones de software. Artículos procedentes del área de la gestión de la producción se centran en el análisis de coste y beneficio de las implantaciones de sistemas. La revisión de la literatura revela que el éxito de las TI para la coordinación de redes industriales depende en gran medida de características de tres dimensiones: la configuración de la red industrial, los esquemas de coordinación y las funcionalidades del software. La literatura disponible está enfocada sobre todo en los beneficios de las implantaciones de SCM software. Sin embargo, la coordinación de la cadena de suministro, basándose en el sistema ERP, sigue siendo la práctica industrial generalizada, pero el coste de coordinación asociado no ha sido abordado por los investigadores. Los fundamentos de diseño organizativo eficiente se explican en detalle en la medida necesaria para la comprensión de la síntesis de las diferentes formas de organización. Se han generado varios esquemas de coordinación variando los siguientes parámetros de diseño: la estructura organizativa, los mecanismos de coordinación y el soporte por TI. Las diferentes propuestas de organización desarrolladas son evaluadas por un método heurístico y otro basado en la simulación por eventos discretos. Para ambos métodos, se tienen en cuenta los principios de la teoría de la organización. La falta de rendimiento empresarial se debe a las dependencias entre actividades que no se gestionan adecuadamente. Dentro del método heurístico, se clasifican las dependencias y se mide su intensidad basándose en factores contextuales. A continuación, se valora la idoneidad de cada elemento de diseño organizativo para cada dependencia específica. Por último, cada forma de organización se evalúa basándose en la contribución de los elementos de diseño tanto al beneficio como al coste. El beneficio de coordinación se refiere a la mejora en el rendimiento logístico - este concepto es el objeto central en la mayoría de modelos de evaluación de la gestión de la cadena de suministro. Por el contrario, el coste de coordinación que se debe incurrir para lograr beneficios no se suele considerar en detalle. Procesos iterativos son costosos si se ejecutan manualmente. Este es el caso cuando SCM software no está implementada y el sistema ERP es el único instrumento de coordinación disponible. El modelo heurístico proporciona un procedimiento simplificado para la clasificación sistemática de las dependencias, la cuantificación de los factores de influencia y la identificación de configuraciones que indican el uso de formas organizativas y de soporte de TI más o menos complejas. La simulación de eventos discretos se aplica en el segundo modelo de evaluación utilizando el paquete de software ‘Plant Simulation’. Con respecto al rendimiento logístico, por un lado se mide el coste de fabricación, de inventario y de transporte y las penalizaciones por pérdida de ventas. Por otro lado, se cuantifica explícitamente el coste de la coordinación teniendo en cuenta los ciclos de coordinación iterativos. El método se aplica a una configuración de cadena de suministro ejemplar considerando diversos parámetros. Los resultados de la simulación confirman que, en la mayoría de los casos, el beneficio aumenta cuando se intensifica la coordinación. Sin embargo, en ciertas situaciones en las que se aplican ciclos de planificación manuales e iterativos el coste de coordinación adicional no siempre conduce a mejor rendimiento logístico. Estos resultados inesperados no se pueden atribuir a ningún parámetro particular. La investigación confirma la gran importancia de nuevas dimensiones hasta ahora ignoradas en la evaluación de propuestas organizativas y herramientas de TI. A través del método heurístico se puede comparar de forma rápida, pero sólo aproximada, la eficiencia de diferentes formas de organización. Por el contrario, el método de simulación es más complejo pero da resultados más detallados, teniendo en cuenta parámetros específicos del contexto del caso concreto y del diseño organizativo. ABSTRACT Transactional systems such as Enterprise Resource Planning (ERP) systems have been implemented widely while analytical software like Supply Chain Management (SCM) add-ons are adopted less by manufacturing companies. Although significant benefits are reported stemming from SCM software implementations, companies are reluctant to invest in such systems. On the one hand this is due to the lack of methods that are able to detect benefits from the use of SCM software and on the other hand associated costs are not identified, detailed and quantified sufficiently. Coordination schemes based only on ERP systems are valid alternatives in industrial practice because significant investment in IT can be avoided. Therefore, the evaluation of these coordination procedures, in particular the cost due to iterations, is of high managerial interest and corresponding methods are comprehensive tools for strategic IT decision making. The purpose of this research is to provide evaluation methods that allow the comparison of different organizational forms and software support levels. The research begins with a comprehensive introduction dealing with the business environment that industrial networks are facing and concludes highlighting the challenges for the supply chain software industry. Afterwards, the central terminology is addressed, focusing on organization theory, IT investment peculiarities and supply chain management software typology. The literature review classifies recent supply chain management research referring to organizational design and its software support. The classification encompasses criteria related to research methodology and content. Empirical studies from management science focus on network types and organizational fit. Novel planning algorithms and innovative coordination schemes are developed mostly in the field of operations research in order to propose new software features. Operations and production management researchers realize cost-benefit analysis of IT software implementations. The literature review reveals that the success of software solutions for network coordination depends strongly on the fit of three dimensions: network configuration, coordination scheme and software functionality. Reviewed literature is mostly centered on the benefits of SCM software implementations. However, ERP system based supply chain coordination is still widespread industrial practice but the associated coordination cost has not been addressed by researchers. Fundamentals of efficient organizational design are explained in detail as far as required for the understanding of the synthesis of different organizational forms. Several coordination schemes have been shaped through the variation of the following design parameters: organizational structuring, coordination mechanisms and software support. The different organizational proposals are evaluated using a heuristic approach and a simulation-based method. For both cases, the principles of organization theory are respected. A lack of performance is due to dependencies between activities which are not managed properly. Therefore, within the heuristic method, dependencies are classified and their intensity is measured based on contextual factors. Afterwards the suitability of each organizational design element for the management of a specific dependency is determined. Finally, each organizational form is evaluated based on the contribution of the sum of design elements to coordination benefit and to coordination cost. Coordination benefit refers to improvement in logistic performance – this is the core concept of most supply chain evaluation models. Unfortunately, coordination cost which must be incurred to achieve benefits is usually not considered in detail. Iterative processes are costly when manually executed. This is the case when SCM software is not implemented and the ERP system is the only available coordination instrument. The heuristic model provides a simplified procedure for the classification of dependencies, quantification of influence factors and systematic search for adequate organizational forms and IT support. Discrete event simulation is applied in the second evaluation model using the software package ‘Plant Simulation’. On the one hand logistic performance is measured by manufacturing, inventory and transportation cost and penalties for lost sales. On the other hand coordination cost is explicitly considered taking into account iterative coordination cycles. The method is applied to an exemplary supply chain configuration considering various parameter settings. The simulation results confirm that, in most cases, benefit increases when coordination is intensified. However, in some situations when manual, iterative planning cycles are applied, additional coordination cost does not always lead to improved logistic performance. These unexpected results cannot be attributed to any particular parameter. The research confirms the great importance of up to now disregarded dimensions when evaluating SCM concepts and IT tools. The heuristic method provides a quick, but only approximate comparison of coordination efficiency for different organizational forms. In contrast, the more complex simulation method delivers detailed results taking into consideration specific parameter settings of network context and organizational design.