A novel approach to study realistic navigations on networks

We consider navigation or search schemes on networks which are realistic in the sense that not all search chains can be completed. We show that the quantity $\mu = \rho/s_d$, where $s_d$ is the average dynamic shortest distance and $\rho$ the success rate of completion of a search, is a consistent measure for the quality of a search strategy. Taking the example of realistic searches on scale-free networks, we find that $\mu$ scales with the system size $N$ as $N^{-\delta}$, where $\delta$ decreases as the searching strategy is improved. This measure is also shown to be sensitive to the distintinguishing characteristics of networks. In this new approach, a dynamic small world (DSW) effect is said to exist when $\delta \approx 0$. We show that such a DSW indeed exists in social networks in which the linking probability is dependent on social distances.Comment: Text revised, references added; accepted version in Journal of Statistical Mechanic

Is the New Resonance Spin 0 or 2? Taking a Step Forward in the Higgs Boson Discovery

The observation of a new boson of mass \sim 125\gev at the CERN LHC may finally have revealed the existence of a Higgs boson. Now we have the opportunity to scrutinize its properties, determining its quantum numbers and couplings to the standard model particles, in order to confirm or not its discovery. We show that by the end of the 8 TeV run, combining the entire data sets of ATLAS and CMS, it will be possible to discriminate between the following discovery alternatives: a scalar $J^P=0^+$ or a tensor $J^P=2^+$ particle with minimal couplings to photons, at a $5\sigma$ statistical confidence level at least, using only diphotons events. Our results are based on the calculation of a center-edge asymmetry measure of the reconstructed {\it sPlot} scattering polar angle of the diphotons. The results based on asymmetries are shown to be rather robust against systematic uncertainties with comparable discrimination power to a log likelihood ratio statistic.Comment: 11 pages, 6 figures, 1 table. References added, minor typos correcte

MEDUSA - New Model of Internet Topology Using k-shell Decomposition

The k-shell decomposition of a random graph provides a different and more insightful separation of the roles of the different nodes in such a graph than does the usual analysis in terms of node degrees. We develop this approach in order to analyze the Internet's structure at a coarse level, that of the "Autonomous Systems" or ASes, the subnetworks out of which the Internet is assembled. We employ new data from DIMES (see http://www.netdimes.org), a distributed agent-based mapping effort which at present has attracted over 3800 volunteers running more than 7300 DIMES clients in over 85 countries. We combine this data with the AS graph information available from the RouteViews project at Univ. Oregon, and have obtained an Internet map with far more detail than any previous effort. The data suggests a new picture of the AS-graph structure, which distinguishes a relatively large, redundantly connected core of nearly 100 ASes and two components that flow data in and out from this core. One component is fractally interconnected through peer links; the second makes direct connections to the core only. The model which results has superficial similarities with and important differences from the "Jellyfish" structure proposed by Tauro et al., so we call it a "Medusa." We plan to use this picture as a framework for measuring and extrapolating changes in the Internet's physical structure. Our k-shell analysis may also be relevant for estimating the function of nodes in the "scale-free" graphs extracted from other naturally-occurring processes.Comment: 24 pages, 17 figure

From non-Brownian Functionals to a Fractional Schr\"odinger Equation

We derive backward and forward fractional Schr\"odinger type of equations for the distribution of functionals of the path of a particle undergoing anomalous diffusion. Fractional substantial derivatives introduced by Friedrich and co-workers [PRL {\bf 96}, 230601 (2006)] provide the correct fractional framework for the problem at hand. In the limit of normal diffusion we recover the Feynman-Kac treatment of Brownian functionals. For applications, we calculate the distribution of occupation times in half space and show how statistics of anomalous functionals is related to weak ergodicity breaking.Comment: 5 page

Transport in networks with multiple sources and sinks

We investigate the electrical current and flow (number of parallel paths) between two sets of n sources and n sinks in complex networks. We derive analytical formulas for the average current and flow as a function of n. We show that for small n, increasing n improves the total transport in the network, while for large n bottlenecks begin to form. For the case of flow, this leads to an optimal n* above which the transport is less efficient. For current, the typical decrease in the length of the connecting paths for large n compensates for the effect of the bottlenecks. We also derive an expression for the average flow as a function of n under the common limitation that transport takes place between specific pairs of sources and sinks

Data Citizenship: Data Literacies to Challenge Power Imbalance Between Society and “Big Tech”

We argue here that data literacies and capabilities are an integral part of data justice. Based on focus group data collected as part of a 3-year empirical project research project, we find that citizens remain unaware of key aspects of the digital ecosystem, which exacerbate the power imbalance between big technology (data processors) companies and citizens (data subjects). Citizens feel concerned about the way it is operating, they do not feel confident enough to be able to address that. We find that “networks of literacy” among friends, colleagues, and trusted organizations are crucial for citizens’ capabilities. These networks influence citizens’ ability to convert their available means into capabilities to support civic engagement and their communities

Chapter 12 - Developing and Delivering Data Literacy

In this chapter we present our own work on developing the idea of Data Literacy and reflect on the potential to develop democratic education for data citizenship. In our work we link ideas from Dewey (New Republic 61:294–296, 1930) and Freire (Pedagogy of the oppressed (revised). Continuum, 1970/1996), with ideas from Nussbaum (Int Stud Rev 4(2), 123–135, 2002) and Sen (The idea of justice. Harvard University Press, 2009), to consider how we move towards a more just datafied society (see Carmi E, Yates S, Int J Commun 17:3619–3637, 2023). We argue that Data Literacy and Data Citizenship interventions need to build on a deep understanding of their audience and their journey towards greater data citizenship and awareness of issues in our datafied society. The chapter sets out seven principles for the development of Data Literacy and data citizenship support interventions and explores approaches to their development

Chapter 1 - Introduction

This book developed from the “Digital Inclusion Policy and Research Conference 2021”. This was the third in a series of conferences that brought together, academic researchers, policy makers and practitioners. The chapters presented here represent the breadth of topics explored at the conference. The conference took place – online – at the height of the COVID-19 pandemic and as a result several the chapters here explore issues that arose or interventions that took place in response to COVID-19. This is not just a curiosity of timing but reflects a key shift in thinking, especially policy, thinking about digital exclusion and strategies for digital inclusion. COVID-19 lockdowns drove a range of responses. Many governments their agencies, health providers, community groups and businesses shifted “online”. There were many potential benefits with this shift – but it also left a lot of people behind. In fact, from our own experience and discussions with governments and civic stakeholders, we can confidently say that levels of digital inequality – not just absolute digital exclusion – caught many organisations off guard. Levels of digital access (e.g., broadband speeds), equipment, spaces in the home to use digital kit, distribution across families, as well as individual and household digital literacies were all found to be wanting or much lower than assumed

Digital Inclusion International Policy and Research

This collection presents policy and research that addresses digital inequalities, access, and skills, from multiple international perspectives

Search in Complex Networks : a New Method of Naming

We suggest a method for routing when the source does not posses full information about the shortest path to the destination. The method is particularly useful for scale-free networks, and exploits its unique characteristics. By assigning new (short) names to nodes (aka labelling) we are able to reduce significantly the memory requirement at the routers, yet we succeed in routing with high probability through paths very close in distance to the shortest ones.Comment: 5 pages, 4 figure