Cascades of Coverage: Dynamics of Media Attention to Social Movement Organizations

Gaining attention in the mass media is a key goal of many social movement organizations (SMOs). The dominant explanation of media attention to SMOs is that the media act like a filter, selecting some types of SMOs and events for attention, and ignoring others based on characteristics of these SMOs, events, and their political environment. In contrast to this “bias model,” I argue that some media attention to SMOs is characterized by positive feedback, or rich-get-richer processes: past media attention increases the likelihood of future media attention through its effect on the SMO and on other media outlets. Like other positive feedback systems, media attention can be path dependent, is routinely punctuated by large cascades of attention to previously obscure SMOs, and can be contingent on “accidents” of history: at critical junctures, individuals, organizations, and events have the potential to radically impact the extent of media attention to their movements and organizations. Media attention to SMOs can also become decoupled from the types of events that initially sparked their media attention, becoming spokes-organizations for their movements and receiving media attention for events and stories that they themselves are not involved. In support of this theory, I first show that media attention is, similar to other positive feedback processes, power-law distributed across SMOs using two national (US) data sets. I then illustrate the process of positive feedback in media attention through a case study of the Black Panther Party's rise to prominence in media attention

Model based safety analysis for an Unmanned Aerial System

This paper aims at describing safety architectures of autonomous systems by using Event-B formal method. The autonomous systems combine various activities which can be organised in layers. The Event-B formalism well supports the rigorous design of this kind of systems. Its refinement mechanism allows a progressive modelling by checking the correctness and the relevance of the models by discharging proof obligations. The application of the Event-B method within the framework of layered architecture specification enables the emergence of desired global properties with relation to layer interactions. The safety objectives are derived in each layer and they involve static and dynamic properties such as an independence property, a redundant property or a sequential property. The originality of our approach is to consider a refinement process between two layers in which the abstract model is the model of the lower layer. In our modelling, we distinguish nominal behaviour and abnormal behaviour in order to well establish failure propagation in our architecture

Making a National Crime: The Transformation of US Lynching Politics 1883-1930

Between the Post-Civil War Reconstruction era and stretching into the beginning of the Civil Rights era, a dramatic shift occurred in the public representations of lynching. Lynching was originally framed as a form of rough justice and popular sovereignty—a necessary response to the heinous crimes of blacks and slow courts. But, over this period, roughly 1883-1930, lynching came to be understood as a form of brutality, anarchy, and “barbarism”. This dissertation addresses the causes and consequences of the changing meanings of lynching. I argue that lynching was increasingly criticized as lynch mobs victimized people from outside of the usual black Southern victims, and thus expanded the scope of anti-lynching politics.Doctor of Philosoph

Avalanches of Attention: Positive Feedback in Media Coverage of Social Movement Organizations

I present a positive feedback model to explain why media attention to SMOs is so unequal, volatile and unpredictable. Receiving some degree of media attention helps groups to receive still more--a cumulative advantage, or rich-get-richer, process. The model presents two empirically verifiable implications: (1) levels of media attention will be power-law distributed across SMOs and (2) coverage dynamics will be path-dependent and thus potentially sensitive to small events early in organization histories. Using new methodology from statistical physics I show that media attention is indeed power-law distributed within three large datasets describing counts of media stories to SMOs spanning multiple movements, time periods and media outlets. I then explore the path dependent nature of media coverage with a comparative analysis of the Black Panther Party and the Revolutionary Action Movement. The two groups were initially very similar, the Black Panthers, however, were able to turn early media attention into further media attention, while the Revolutionary Action Movement was not, eventually resulting in a roughly eighty fold difference in levels of media attention between the two groups. Jointly, the quantitative and qualitative results provide broad support for the positive feedback model.Master of Art

Analyse de sécurité de systèmes autonomes: formalisation et évaluation en Event-B

Cet article présente une partie de l'étude d'architectures de sécurité de systèmes autonomes s'appuyant sur l'utilisation de la méthode formelle Event-B. Le formalisme Event-B supporte bien la conception rigoureuse de ces systèmes qui combinent diverses activités que l'on peut structurer en couches. Sa technique de raffinement permet une modélisation progressive en vérifiant la correction et la pertinence des modèles par décharge de preuves. L'application de la méthode Event-B dans le cadre de la spécification d'architectures en couches garantit l'émergence de propriétés globales attendues, telles que les propriétés de sécurité, lorsque l'on s'assure du respect de propriétés au niveau des relations entre les couches. Cet article se situe au début de cette nouvelle étude. Il présente les principes de la modélisation Event-B d'un système de contrôle de drone simplifié. Il caractérise le concept d'architecture en couches utilisée pour cette modélisation. Il décrit ensuite une première modélisation d'une couche avant de conclure sur l'intérêt de cette modélisation pour la validation de systèmes autonomes par rapport aux objectifs de sécurité fixés

Model based system assessment: formalisation et évaluation de systèmes autonomes en Event-B

Cet article vise à décrire une architecture de sécurité de systèmes autonomes à l’aide de la méthode formelle Event-B. Le formalisme Event-B supporte une conception rigoureuse de ces systèmes. La technique de raffinement permet une modélisation progressive en vérifiant la correction et la pertinence des modèles par décharge de preuves. L’application de la méthode Event-B présente un intérêt dans la formalisation des relations entre couches qui assurent la cohérence d’un fonctionnement sûr ainsi que le respect des exigences de sécurité concernées par notre analyse. Par conséquent, la modélisation autour de ces relations fait apparaître en permanence un comportement nominal associé à des comportements en présence de fautes sous l’hypothèse d’une architecture intégrant des mécanismes de tolérance aux fautes

Governance traditions and narratives of public sector reform in contemporary France.

This article explores the basic traditions of governance in contemporary France and the narratives of public sector reform associated with them. It should be stressed right from the outset that this article does not aim to describe the set of public sector reforms that have been implemented in France in the last ten years or so. Instead, the aim is to demonstrate the similarities and differences between the narratives of the left and the right with regard to these reforms and to show how these narratives help to explain the types of reform that have been enacted. The basic argument is that there is a certain commonality to both the left and the right with regard to their narratives of public sector reform. At the same time, though, there are differences of emphasis both within each tradition and between the two main traditions themselves. Except where indicated, all translations are the author's own

The European Prevalence of Resistance Associated Substitutions among Direct Acting Antiviral Failures

Background: Approximately 71 million people are still in need of direct-acting antiviral agents (DAAs). To achieve the World Health Organization Hepatitis C elimination goals, insight into the prevalence and influence of resistance associated substitutions (RAS) is of importance. Collaboration is key since DAA failure is rare and real-life data are scattered. We have established a European collaboration, HepCare, to perform in-depth analysis regarding RAS prevalence, patterns, and multiclass occurrence. Methods: Data were extracted from the HepCare cohort of patients who previously failed DAA therapy. Geno-and subtypes were provided by submitters and mostly based on in-house assays. They were reassessed using the Comet HCV subtyping tool. We considered RAS to be relevant if they were associated with DAA failure in vivo previously reported in literature. Results: We analyzed 938 patients who failed DAA therapy from ten different European countries. There were 239 genotypes (GT) 1a, 380 GT1b, 19 GT2c, 205 GT3a, 14 GT4a, and 68 GT4d infections. Several unusual subtypes (n = 15) (GT1b/g/l, GT3b, GT4k/n/r/t) were present. RAS appeared in over 80% of failures and over a quarter had three or more RAS. Multiclass RAS varied over target region and genotype between 0-48%. RAS patterns such as the Q30R + L31M and Q30R + Y93H in GT1a, the L31V + Y93H and L31V + Y93H for GT1b, and A30K + L31M and A30K/V + Y93H for GT3a all occurred with a prevalence below 5%. Conclusion: RAS occur frequently after DAA failures and follow a specific genotype and drug related pattern. Interpretation of the influence of RAS on retreatment is challenging due to various patterns, patients' characteristics, and previous treatment history. Moving towards HCV elimination, an ongoing resistance surveillance is essential to track the presence of RAS, RAS patterns and gather data for a re-treatment algorithm