New Media, New Politics: The Emergence of the Internet in American Politics

The Internet is viewed by some as a great tool for democracy. Indeed, if we believe in the value of a marketplace of ideas, there is no greater forum through which individuals can express any and every opinion on a variety of issues than the Internet. However, it is unclear whether this free and unfettered expression of ideas has been helpful or harmful to American democracy. This dissertation demonstrates, through the use of National Election Studies (NES) data that those using the Internet tend to have more negative attitudes toward political leaders and institutions than their counterparts who either do not use the Internet or make use of more traditional media. In particular, the dissertation explores the possibility that unique features of online news (namely comment sections for the purposes of this study) exacerbate the lack of trust and confidence that individuals have in their government. Additionally, data from the Pew Center shows that those taking advantage of the opportunity to post in these online comment sections tend to have demographic characteristics suggestive of increased levels of social isolation relative to those who do not post comments. Finally, a unique experimental design on the University of Missouri-St. Louis campus shows that articles with online comment sections are viewed as being more “rude” or “hostile” in tone than the same articles without the presence of a comment section. Ultimately, the findings suggest that there are reasons to be concerned about the way in which individuals gather political information and formulate political attitudes in this digital age

Cognitive Conceptualizations and Schemata as Predictors of Distress in Female Rape Victims

Rape is strikingly prevalent among undergraduate women, and victims show significant variability in their reactions to sexual victimization. The aim of this longitudinal study was to examine two cognitive processing factors that have been theorized to impact a woman’s levels of distress after being raped. One cognitive factor, rape conceptualization, broadly refers to the way a woman comes to understand and interpret the event as identified by her attributions of blame and perceptions of severity, wantedness, and consent. Schemata—or global, enduring beliefs about the self and world—represent the other cognitive factor examined in this study. Participants included 189 undergraduate women from a Midwestern public institution, who endorsed a behaviorally-defined rape experience. Cross-sectional results from Study 1 indicated that all aspects of conceptualization were significantly associated with maladaptive schemata. Furthermore, results confirmed a predicted mediation; maladaptive beliefs a woman holds about herself mediate the impact that blaming her enduring traits has on distress. Forty-four rape victims completed a follow-up study, and results indicated that, overall, there were minimal changes in the participants’ conceptualizations of a specific rape experience and little difference in the maladaptive beliefs they held. Time 2 results also suggested that there appeared to be two separate groups of victims in this highly distressed sample—those whose symptoms improved over time and whose symptoms worsened over time. The hypothesized relationship between changes in cognitive processing factors and changes in distress was not confirmed in the longitudinal, follow-up study. Implications for cognitive processing theories, individualized treatment for rape victims, and future research directions are discussed

First-passage distributions for the one-dimensional Fokker-Planck equation

We present an analytical framework to study the first-passage (FP) and first-return (FR) distributions for the broad family of models described by the one-dimensional Fokker-Planck equation in finite domains, identifying general properties of these distributions for different classes of models. When in the Fokker-Planck equation the diffusion coefficient is positive (nonzero) and the drift term is bounded, as in the case of a Brownian walker, both distributions may exhibit a power-law decay with exponent -3/2 for intermediate times. We discuss how the influence of an absorbing state changes this exponent. The absorbing state is characterized by a vanishing diffusion coefficient and/or a diverging drift term. Remarkably, the exponent of the Brownian walker class of models is still found, as long as the departure and arrival regions are far enough from the absorbing state, but the range of times where the power law is observed narrows. Close enough to the absorbing point, though, a new exponent may appear. The particular value of the exponent depends on the behavior of the diffusion and the drift terms of the Fokker-Planck equation. We focus on the case of a diffusion term vanishing linearly at the absorbing point. In this case, the FP and FR distributions are similar to those of the voter model, characterized by a power law with exponent -2. As an illustration of the general theory, we compare it with exact analytical solutions and extensive numerical simulations of a two-parameter voter-like family models. We study the behavior of the FP and FR distributions by tuning the importance of the absorbing points throughout changes of the parameters. Finally, the possibility of inferring relevant information about the steady-sate probability distribution of a model from the FP and FR distributions is addressed.Comment: 17 pages, 8 figure

Evaluation of Effectiveness of Risk Minimisation Measures in Europe

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Medicina, Departamento de Medicina. Fecha de Lectura: 02-06-202

Joint effect of ageing and multilayer structure prevents ordering in the voter model

The voter model rules are simple, with agents copying the state of a random neighbor, but they lead to non-trivial dynamics. Besides opinion processes, the model has also applications for catalysis and species competition. Inspired by the temporal inhomogeneities found in human interactions, one can introduce ageing in the agents: the probability to update decreases with the time elapsed since the last change. This modified dynamics induces an approach to consensus via coarsening in complex networks. Additionally, multilayer networks produce profound changes in the dynamics of models. In this work, we investigate how a multilayer structure affects the dynamics of an ageing voter model. The system is studied as a function of the fraction of nodes sharing states across layers (multiplexity parameter q ). We find that the dynamics of the system suffers a notable change at an intermediate value q*. Above it, the voter model always orders to an absorbing configuration. While, below, a fraction of the realizations falls into dynamical traps associated to a spontaneous symmetry breaking in which the majority opinion in the different layers takes opposite signs and that due to the ageing indefinitely delay the arrival at the absorbing state.Comment: 10 pages, 8 figure

Estudio del Practicum de Pedagogía : alternativas metodológicas

La finalidad del presente trabajo es doble, en primer lugar establecer una reflexión sobre las aportaciones que los diferentes métodos y técnicas de investigación educativa representan en los estudios e investigaciones sobre el Practicum y, en segundo lugar, analizar el nivel de satisfacción, expectativas y demandas de los estudiantes que participan en el Practicum II de los estudios de Pedagogía en la Universidad de Oviedo. Los instrumentos de evaluación utilizados han sido el cuestionario, análisis de documentos oficiales escritos, grupos de discusión y entrevistas a informantes clave. Los resultados del estudio muestran una valoración positiva por parte de los estudiantes del actual modelo de Practicum, si bien es cierto han emergido aspectos susceptibles de mejora que deberán adaptarse a la línea sugerida por los presupuestos que informan el Espacio Europeo de Educación Superio

Effectiveness of dismantling strategies on moderated vs. unmoderated online social platforms

Online social networks are the perfect test bed to better understand large-scale human behavior in interacting contexts. Although they are broadly used and studied, little is known about how their terms of service and posting rules affect the way users interact and information spreads. Acknowledging the relation between network connectivity and functionality, we compare the robustness of two different online social platforms, Twitter and Gab, with respect to dismantling strategies based on the recursive censor of users characterized by social prominence (degree) or intensity of inflammatory content (sentiment). We find that the moderated (Twitter) vs unmoderated (Gab) character of the network is not a discriminating factor for intervention effectiveness. We find, however, that more complex strategies based upon the combination of topological and content features may be effective for network dismantling. Our results provide useful indications to design better strategies for countervailing the production and dissemination of anti-social content in online social platforms

Abrupt transition due to non-local cascade propagation in multiplex systems

Multilayer systems are coupled networks characterized by different contexts (layers) of interaction and have gained much attention recently due to their suitability to describe a broad spectrum of empirical complex systems. They are very fragile to percolation and first-neighbor failure propagation, but little is known about how they respond to non-local disruptions, as it occurs in failures induced by flow redistribution, for example. Acknowledging that many socio-technical and biological systems sustain a flow of some physical quantity, such as energy or information, across the their components, it becomes crucial to understand when the flow redistribution can cause global cascades of failures in order to design robust systems,to increase their resilience or to learn how to efficiently dismantle them. In this paper we study the impact that different multiplex topological features have on the robustness of the system when subjected to non-local cascade propagation. We first numerically demonstrate that this dynamics has a critical value at which a small initial perturbation effectively dismantles the entire network, and that the transition appears abruptly. Then we identify that the excess of flow caused by a failure is, in general, more homogeneously distributed the networks in which the average distance between nodes is small.Using this information we find that aggregated versions of multiplex networks tend to overestimate robustness, even though to make the system more robust can be achieved by increasing the number of layers. Our predictions are confirmed by simulated cascading failures in areal multilayer system

Efficient network exploration by means of resetting self-avoiding random walkers

The self-avoiding random walk (SARW) is a stochastic process whose state variable avoids returning to previously visited states. This non-Markovian feature has turned SARWs a powerful tool for modelling a plethora of relevant aspects in network science, such as network navigability, robustness and resilience. We analytically characterize self-avoiding random walkers that evolve on complex networks and whose memory suffers stochastic resetting, that is, at each step, with a certain probability, they forget their previous trajectory and start free diffusion anew. Several out-of-equilibrium properties are addressed, such as the time-dependent position of the walker, the time-dependent degree distribution of the non-visited network and the first-passage time distribution, and its moments, to target nodes. We examine these metrics for different resetting parameters and network topologies, both synthetic and empirical, and find a good agreement with simulations in all cases. We also explore the role of resetting on network exploration and report a non-monotonic behavior of the cover time: frequent memory resets induce a global minimum in the cover time, significantly outperforming the well-known case of the pure random walk, while reset events that are too spaced apart become detrimental for the network discovery. Our results provide new insights into the profound interplay between topology and dynamics in complex networks, and shed light on the fundamental properties of SARWs in nontrivial environments.Comment: 10 pages & 3 figures; Supp. Mat.: 11 pages & 15 figure