Search results for "Network Analysi"

Il problema sociologico dell’altruismo: inquadramento teorico e sviluppi metodologici

2011

American Horror Story e i suoi fan italiani: interazioni e costruzione del discorso on-line

2020

A partire dal concetto sociologico di “audience performativa”, che contraddistingue alcune forme della spettatorialità televisiva contemporanea, in questo contributo prendo in considerazione l’attività di produzione dei fan; in particolare, la produttività testuale e discorsiva, che è spesso riferita alle serie TV. Discuto, poi, il posto dell’horror nella narrazione seriale, traendo spunto da American Horror Story, la serie di successo ideata, nel 2011, da Ryan Murphy e Brad Falchuk. Quindi, attraverso una ricerca empirica di tipo quali-quantitativo, provo a descrivere e spiegare le modalità d’interazione e i discorsi dei fan italiani, iscritti ad una pagina Facebook dedicata alla serie, fa…

Riflessività, interazione e rispetto delle norme. Il contributo dei mixed methods tra analisi dei testi e social network analysis

2018

The book, through a special methodological mix that uses text analysis and social network analysis, explores the ways in which people, starting from some elements considered implicit, are able to problematize specific behaviours. People contribute differently to social change or reproduction, by selecting certain aspects of reality and attributing to these aspects power of constraint or facilitation. Starting from the theoretical approach of Margaret Archer, which looks at the reflexivity of social actors as the capacity to develop an internal conversation, which is able to mediate between structure and agency, the book deals with the dynamics that take place when reflexive types converse o…

Dynamic network identification from non-stationary vector autoregressive time series

2018

Learning the dynamics of complex systems features a large number of applications in data science. Graph-based modeling and inference underpins the most prominent family of approaches to learn complex dynamics due to their ability to capture the intrinsic sparsity of direct interactions in such systems. They also provide the user with interpretable graphs that unveil behavioral patterns and changes. To cope with the time-varying nature of interactions, this paper develops an estimation criterion and a solver to learn the parameters of a time-varying vector autoregressive model supported on a network of time series. The notion of local breakpoint is proposed to accommodate changes at individu…

Numerical approach for signal delay in general distributed networks

2003

The authors consider a general network with telegraph equations modelling distributed elements and having, additionally, nonlinear capacitors. A global asymptotic exponential stability of the solution is given. A simple computable upper bound of the delay time is given. Numerical examples illustrate the usefulness of the results. >

Algorithms for Graph and Network Analysis: Graph Alignment

2019

In this article we discuss the problem of graph alignment, which has been longly referred to for the purpose of analyzing and comparing biological networks. In particular, we describe different facets of graph alignment, according to the number of input networks, the fixed output objective, the possible heterogeneity of input data. Accordingly, we will discuss pairwise and multiple alignment, global and local alignment, etc. Moreover, we provide a comprehensive overview of the algorithms and techniques proposed in the literature to solve each of the specific considered types of graph alignment. In order to make the material presented here complete and useful to guide the reader in the use o…

A Comparison of Dyadic and Social Network Assessments of Peer Influence.

2021

The present study compares two methods for assessing peer influence: the longitudinal actor–partner interdependence model (L-APIM) and the longitudinal social network analysis (L-SNA) Model. The data were drawn from 1,995 (49% girls and 51% boys) third grade students ( Mage= 9.68 years). From this sample, L-APIM ( n = 206 indistinguishable dyads and n = 187 distinguishable dyads) and L-SNA ( n = 1,024 total network members) subsamples were created. Students completed peer nominations and objective assessments of mathematical reasoning in the spring of the third and fourth grades. Patterns of statistical significance differed across analyses. Stable distinguishable and indistinguishable L-AP…

Overlapping Community Structure in Co-authorship Networks: A Case Study

2014

Community structure is one of the key properties of real-world complex networks. It plays a crucial role in their behaviors and topology. While an important work has been done on the issue of community detection, very little attention has been devoted to the analysis of the community structure. In this paper, we present an extensive investigation of the overlapping community network deduced from a large-scale co-authorship network. The nodes of the overlapping community network represent the functional communities of the co-authorship network, and the links account for the fact that communities share some nodes in the co-authorship network. The comparative evaluation of the topological prop…

Multilayer Network Analysis: The Identification of Key Actors in a Sicilian Mafia Operation

2021

Recently, Social Network Analysis studies have led to an improvement and to a generalization of existing tools to networks with multiple subsystems and layers of connectivity. These kind of networks are usually called multilayer networks. Multilayer networks in which each layer shares at least one node with some other layer in the network are called multiplex networks. Being a multiplex network does not require all nodes to exist on every layer. In this paper, we built a criminal multiplex network which concerns an anti-mafia operation called “Montagna” and it is based on the examination of a pre-trial detention order issued on March 14, 2007 by the judge for preliminary investigations of t…

Correlations among Game of Thieves and other centrality measures in complex networks

2021

Social Network Analysis (SNA) is used to study the exchange of resources among individuals, groups, or organizations. The role of individuals or connections in a network is described by a set of centrality metrics which represent one of the most important results of SNA. Degree, closeness, betweenness and clustering coefficient are the most used centrality measures. Their use is, however, severely hampered by their computation cost. This issue can be overcome by an algorithm called Game of Thieves (GoT). Thanks to this new algorithm, we can compute the importance of all elements in a network (i.e. vertices and edges), compared to the total number of vertices. This calculation is done not in…