WAIS Seminar:Modelling the Web: Examples of modelling language, network evolution and physical-social systems

Speaker(s): Prof. Steffen Staab Organiser: Dr Tim Chown Time: 23/05/2014 10:30-11:30 Location: B53/4025 Abstract The Web is constructed based on our experiences in a multitude of modalities: text, networks, images, physical locations are some examples. Understanding the Web requires from us that we can model these modalities as they appear on the Web. In this talk I will show some examples of how we model text, hyperlink networks and physical-social systems in order to improve our understanding and our use of the Web.

The Network is us

Larry Johnson, Presidente del New Media Consortium y fundador del proyecto ���Horizon���, present��, en el marco del V Encuentro Nacional de Rectores, la ponencia ���The Network is Us���. Una exposici��n en donde se explica la importancia de implementar las nuevas tecnolog��as en el desarrollo acad��mico de los colegios y las universidades.

"Thematically Analysing Social Network Content During Disasters Through the Lens of the Disaster Management Lifecycle" & "Investigating Similarity Between Privacy Policies of Social Networking Sites as a Precursor for Standardization"

Abstract 1: Social Networks such as Twitter are often used for disseminating and collecting information during natural disasters. The potential for its use in Disaster Management has been acknowledged. However, more nuanced understanding of the communications that take place on social networks are required to more effectively integrate this information into the processes within disaster management. The type and value of information shared should be assessed, determining the benefits and issues, with credibility and reliability as known concerns. Mapping the tweets in relation to the modelled stages of a disaster can be a useful evaluation for determining the benefits/drawbacks of using data from social networks, such as Twitter, in disaster management.A thematic analysis of tweets��� content, language and tone during the UK Storms and Floods 2013/14 was conducted. Manual scripting was used to determine the official sequence of events, and classify the stages of the disaster into the phases of the Disaster Management Lifecycle, to produce a timeline. Twenty- five topics discussed on Twitter emerged, and three key types of tweets, based on the language and tone, were identified. The timeline represents the events of the disaster, according to the Met Office reports, classed into B. Faulkner���s Disaster Management Lifecycle framework. Context is provided when observing the analysed tweets against the timeline. This illustrates a potential basis and benefit for mapping tweets into the Disaster Management Lifecycle phases. Comparing the number of tweets submitted in each month with the timeline, suggests users tweet more as an event heightens and persists. Furthermore, users generally express greater emotion and urgency in their tweets.This paper concludes that the thematic analysis of content on social networks, such as Twitter, can be useful in gaining additional perspectives for disaster management. It demonstrates that mapping tweets into the phases of a Disaster Management Lifecycle model can have benefits in the recovery phase, not just in the response phase, to potentially improve future policies and activities. Abstract2: The current execution of privacy policies, as a mode of communicating information to users, is unsatisfactory. Social networking sites (SNS) exemplify this issue, attracting growing concerns regarding their use of personal data and its effect on user privacy. This demonstrates the need for more informative policies. However, SNS lack the incentives required to improve policies, which is exacerbated by the difficulties of creating a policy that is both concise and compliant. Standardization addresses many of these issues, providing benefits for users and SNS, although it is only possible if policies share attributes which can be standardized. This investigation used thematic analysis and cross- document structure theory, to assess the similarity of attributes between the privacy policies (as available in August 2014), of the six most frequently visited SNS globally. Using the Jaccard similarity coefficient, two types of attribute were measured; the clauses used by SNS and the coverage of forty recommendations made by the UK Information Commissioner���s Office. Analysis showed that whilst similarity in the clauses used was low, similarity in the recommendations covered was high, indicating that SNS use different clauses, but to convey similar information. The analysis also showed that low similarity in the clauses was largely due to differences in semantics, elaboration and functionality between SNS. Therefore, this paper proposes that the policies of SNS already share attributes, indicating the feasibility of standardization and five recommendations are made to begin facilitating this, based on the findings of the investigation.

Lethal Closeness: The Evolution of a Small-World Drug Trafficking Network

The evolution of the drug trafficking network ���so-called��� ���Cartel del Norte del Valle���, is studied using network analysis methods. We found that the average length between any pair of its members was bounded by 4 ���an attribute of smallworld networks. In this tightly connected network, informational shocks induce fear and the unleashing of searches of threatening nodes, using available paths. Lethal violence ensues in clusters of increasing sizes that fragment the network, without compromising, however, the survival of the largest component, which proved to be resilient to massive violence. In spite of a success from the point of view of head counting, the US��� socialization program for drug traffickers did not effectively change the cyclical dynamics of the drug dealing business: war survivors took over what was left from the old network initiating a new cycle of business and violence.

El rol de las ONG de Espa��a en el internacionalizaci��n de la causa de las Damas de Blanco. Estudio de caso: Solidaridad Espa��ola con Cuba (2005-2012)

El inter��s de este estudio de caso es demostrar el rol de la ONG Solidaridad Espa��ola con Cuba en la creaci��n de una red transnacional de defensa de las Damas de Blanco, un movimiento social cubano disidente. Esto, tras reconocer que el apoyo por parte de ��sta y otras organizaciones e instituciones internacionales es de gran importancia para lograr las reivindicaciones sociales propuestas por las Damas de Blanco, a partir de los hechos ocurridos en la Primavera Negra en el a��o 2003. Tanto las organizaciones como el movimiento social, aseguran que ha existido una violaci��n sistem��tica de los Derechos Humanos de los disidentes de este pa��s, y asimismo, una opresi��n de sus demandas, lo que ha hecho que el apoyo internacional se convierta en la clave de un futuro cambio.

Learn-Nett : Learning network for teachers. 'Learn-Nett : Red de aprendizaje para profesores'.

Learn-nett es uno de los proyectos enmarcados dentro del programa Socrates de la Comunidad Econ��mica Europea, un programa que subvenciona y apoya proyectos de investigaci��n y desarrollo de nuestra comunidad tanto en el campo de la educaci��n como en cualquier area de conocimiento. Learn-nett, es un proyecto de participaci��n conjunta entre diferentes universidades europeas y que tiene como objetivo la formaci��n, la experimentaci��n y la reflexi��n sobre la utilizaci��n de las nuevas herramientas de la informaci��n y la comunicaci��n en la educaci��n.

Competition in two-sided markets with common network externalities

We study competition in two sided markets with common network externality rather than with the standard inter-group e��ects. This type of externality occurs when both groups bene t, possibly with di��erent intensities, from an increase in the size of one group and from a decrease in the size of the other. We explain why common externality is relevant for the health and education sectors. We focus on the symmetric equilibrium and show that when the externality itself satis es an homogeneity condition then platforms pro ts and price structure have some speci c properties. Our results reveal how the rents coming from network externalities are shifted by platforms from one side to other, according to the homogeneity degree. In the speci c but realistic case where the common network externality is homogeneous of degree zero, platform s pro t do not depend on the intensity of the (common) network externality. This is in sharp contrast to conventional results stating that the presence of network externalities in a two-sided market structure increases the intensity of competition when the externality is positive (and decreases it when the externality is negative). Prices are a��ected but in such a way that platforms only transfer rents from consumers to providers.

Doctors�� remuneration schemes and hospital competition in two-sided markets with common network externalities

This paper uses a two-sided market model of hospital competition to study the implications of di��erent remunerations schemes on the physicians�� side. The two-sided market approach is characterized by the concept of common network externality (CNE) introduced by Bardey et al. (2010). This type of externality occurs when occurs when both sides value, possibly with di��erent intensities, the same network externality. We explicitly introduce e��ort exerted by doctors. By increasing the number of medical acts (which involves a costly e��ort) the doctor can increase the quality of service o��ered to patients (over and above the level implied by the CNE). We ��rst consider pure salary, capitation or fee-for-service schemes. Then, we study schemes that mix fee-for-service with either salary or capitation payments. We show that salary schemes (either pure or in combination with fee-for-service) are more patient friendly than (pure or mixed) capitations schemes. This comparison is exactly reversed on the providers��side. Quite surprisingly, patients always loose when a fee-for-service scheme is introduced (pure of mixed). This is true even though the fee-for-service is the only way to induce the providers to exert e��ort and it holds whatever the patients��valuation of this e��ort. In other words, the increase in quality brought about by the fee-for-service is more than compensated by the increase in fees faced by patients.

A Network model of systemic risk : identifying the sources of dependence across institutions

We design a financial network model that explicitly incorporates linkages across institutions through a direct contagion channel, as well as an indirect common exposure channel. In particular, common exposure is setup so as to link the financial to the real sector. The model is calibrated to balance sheet data on the colombian financial sector. Results indicate that commercial banks are the most systemically important financial institutions in the system. Whereas government owned institutions are the most vulnerable institutions in the system.

Health care network formation and policyholders' welfare

We develop a model in which two insurers and two health care providers compete for a fixed mass of policyholders. Insurers compete in premium and offer coverage against financial consequences of health risk. They have the possibility to sign agreements with providers to establish a health care network. Providers, partially altruistic, are horizontally differentiated with respect to their physical address. They choose the health care quality and compete in price. First, we show that policyholders are better off under a competition between conventional insurance rather than under a competition between integrated insurers (Managed Care Organizations). Second, we reveal that the competition between a conventional insurer and a Managed Care Organization (MCO) leads to a similar equilibrium than the competition between two MCOs characterized by a different objective i.e. private versus mutual. Third, we point out that the ex ante providers��� horizontal differentiation leads to an exclusionary equilibrium in which both insurers select one distinct provider. This result is in sharp contrast with frameworks that introduce the concept of option value to model the (ex post) horizontal differentiation between providers.

Network externalities across financial institutions

We propose and estimate a financial distress model that explicitly accounts for the interactions or spill-over effects between financial institutions, through the use of a spatial continuity matrix that is build from financial network data of inter bank transactions. Such setup of the financial distress model allows for the empirical validation of the importance of network externalities in determining financial distress, in addition to institution specific and macroeconomic covariates. The relevance of such specification is that it incorporates simultaneously micro-prudential factors (Basel 2) as well as macro-prudential and systemic factors (Basel 3) as determinants of financial distress. Results indicate network externalities are an important determinant of financial health of a financial institutions. The parameter that measures the effect of network externalities is both economically and statistical significant and its inclusion as a risk factor reduces the importance of the firm specific variables such as the size or degree of leverage of the financial institution. In addition we analyze the policy implications of the network factor model for capital requirements and deposit insurance pricing.

Configuraci��n de la interfaz discurso-gram��tica en el lenguaje del profesor de preescolar en el aula ILE : presentaci��n de una red sist��mica como herramienta para un an��lisis sistem��tico de las funciones reguladoras. Modelling the discourse-grammar interface of ELF pre-school teacher talk (native and non-native) : proposal of a system network enabling the systematic analysis of regulatory functions.

Esta investigaci��n pretende alcanzar dos objetivos. Cubrir el vac��o existente en los estudios de las funciones comunicativas del habla de profesores, en este caso de ingl��s como Lengua Extranjera (ILE) destinado a nivel preescolar, y configurar una interfaz discurso-gram��tica de las funciones reguladoras del lenguaje.. En primer lugar, para lograr un an��lisis discursivo-sem��ntico, en este trabajo se dise��a la Red Sist��mica de Funciones Reguladoras, RSFR, una herramienta que resume las diferentes opciones discursivo-sem��nticas de los contextos de las funciones reguladoras. A continuaci��n, se analizan los datos en el estrato l��xico-gramatical para facilitar conclusiones sobre la relaci��n funci��n-realizaci��n formal. Por ��ltimo se exponen las similitudes y diferencias en la producci��n ling����stica de las funciones reguladoras entre profesores nativos y no nativos.. Las aportaciones m��s destacadas de esta investigaci��n son cuatro: hacer posible un estudio sistem��tico del significado mediante el dise��o de una herramienta; la propuesta de una taxonom��a de funciones reguladoras; el an��lisis de la dependencia entre las funciones reguladoras, y sus realizaciones ling����sticas; y las diferencias encontradas en la comparaci��n del discurso del profesor nativo y no-nativo..

Effect of background, attitudinal and social network variables on PhD students' academic performance : a multimethod approach. 'Efecto de las variables personales, actitudinales y de red social en el rendimiento acad��mico de los estudiantes de doctorado : un enfoque multim��todo'.

Resumen tomado de la publicaci��n

'The Sport Network'.

Monogr��fico con el t��tulo: 'El deporte: di��logo universal'. Resumen tomado de la publicaci��n