Search results for "social networks"
showing 10 items of 164 documents
Disrupting resilient criminal networks through data analysis: The case of Sicilian Mafia
2020
Compared to other types of social networks, criminal networks present hard challenges, due to their strong resilience to disruption, which poses severe hurdles to law-enforcement agencies. Herein, we borrow methods and tools from Social Network Analysis to (i) unveil the structure of Sicilian Mafia gangs, based on two real-world datasets, and (ii) gain insights as to how to efficiently disrupt them. Mafia networks have peculiar features, due to the links distribution and strength, which makes them very different from other social networks, and extremely robust to exogenous perturbations. Analysts are also faced with the difficulty in collecting reliable datasets that accurately describe the…
Whom to befriend to influence people
2020
Alice wants to join a new social network, and influence its members to adopt a new product or idea. Each person $v$ in the network has a certain threshold $t(v)$ for {\em activation}, i.e adoption of the product or idea. If $v$ has at least $t(v)$ activated neighbors, then $v$ will also become activated. If Alice wants to activate the entire social network, whom should she befriend? More generally, we study the problem of finding the minimum number of links that a set of external influencers should form to people in the network, in order to activate the entire social network. This {\em Minimum Links} Problem has applications in viral marketing and the study of epidemics. Its solution can be…
Fake news and infodemia at the time of covid-19
2020
The essay has as its object fake news and excess of pieces of information with particular attention to the pandemic emergency we are currently living: COVID-19. After a careful consideration about what fake news actually are, the paper analyzes the pitfalls concerning the communication through virtual technologies, where social networks let the news reach the user only if they pass some requirements, in order to give the user a personalized experience of being informed. As a result, the profiling process traps the user in a cage, which is a paradox, because the internet it’s literally supposed to be without borders and barriers. The current crisis caused by the global pandemic has brought t…
Forma mentis networks map how nursing and engineering students enhance their mindsets about innovation and health during professional growth
2020
Reconstructing a “forma mentis”, a mindset, and its changes, means capturing how individuals perceive topics, trends and experiences over time. To this aim we use forma mentis networks (FMNs), which enable direct, microscopic access to how individuals conceptually perceive knowledge and sentiment around a topic, providing richer contextual information than machine learning. FMNs build cognitive representations of stances through psycholinguistic tools like conceptual associations from semantic memory (free associations, i.e., one concept eliciting another) and affect norms (valence, i.e., how attractive a concept is). We test FMNs by investigating how Norwegian nursing and engineering stude…
Happy Aged People Are All Alike, While Every Unhappy Aged Person Is Unhappy in Its Own Way
2011
Aging of the world’s population represents one of the most remarkable success stories of medicine and of humankind, but it is also a source of various challenges. The aim of the collaborative cross-cultural European study of adult well being (ESAW) is to frame the concept of aging successfully within a causal model that embraces physical health and functional status, cognitive efficacy, material security, social support resources, and life activity. Within the framework of this project, we show here that the degree of heterogeneity among people who view aging in a positive light is significantly lower than the degree of heterogeneity of those who hold a negative perception of aging. We base…
Prevention of hate speech crimes: digital versus real-life environment
2022
Extending the use of social media and other digital networks, as well as technology development and the impact of the pandemic have raised the problem of how to prevent hateful speech from occurring. Limitations on hate speech closely correlate with restriction of freedom of speech, therefore balance between the two should be met to ensure both fundamental democratic right on the freedom of speech, as well as to restrict limitations on one’s honour, dignity and safety. To answer whether mechanisms for combating the crimes of hate speech in the digital environment are as effective as they are in a real-life situation, the author analyses the international (United Nations) and Council of Euro…
Social Influence Maximization in Hypergraphs
2021
This work deals with a generalization of the minimum Target Set Selection (TSS) problem, a key algorithmic question in information diffusion research due to its potential commercial value. Firstly proposed by Kempe et al., the TSS problem is based on a linear threshold diffusion model defined on an input graph with node thresholds, quantifying the hardness to influence each node. The goal is to find the smaller set of items that can influence the whole network according to the diffusion model defined. This study generalizes the TSS problem on networks characterized by many-to-many relationships modeled via hypergraphs. Specifically, we introduce a linear threshold diffusion process on such …
Evaluating security and privacy issues of social networks based information systems in Industry 4.0
2022
[EN] The present study aimed to analyse the main risks related to security and privacy of social networks based information systems in Industry 4.0. The methodology we used is an innovative exploratory data-driven process divided into three steps. First, we performed sentiment analysis to divide the database composed of 67, 206 tweets into feelings. Second, we applied a topic-modelling algorithm to extract topics. Third, we applied textual analysis to collect insights. A total of 10 topics related to security and privacy issues were identified as results. The paper concludes with a discussion of the challenges and main concerns related to the identified topics.
Distributed Coverage of Ego Networks in F2F Online Social Networks
2016
Although most online social networks rely on a centralized infrastructure, several proposals of Distributed Online Social Networks (DOSNs) have been recently presented. Since in DOSNs user profiles are stored on the peers of the users belonging to the network, one of the main challenges comes from guaranteeing the profile availability when the owner of the data is not online. In this paper, we propose a DOSN based on a friend-to-friend P2P overlay where the user's data is stored only on friend peers. Our approach is based on the ego-network concept, which models the social network from the local point of view of a single user. We propose a distributed algorithm which is based on the notion …
Privacy and temporal aware allocation of data in decentralized online social networks
2017
Distributed Online Social Networks (DOSNs) have recently been proposed to grant users more control over the data they share with the other users. Indeed, in contrast to centralized Online Social Networks (such as Facebook), DOSNs are not based on centralized storage services, because the contents shared by the users are stored on the devices of the users themselves. One of the main challenges in a DOSN comes from guaranteeing availability of the users' contents when the data owner disconnects from the network. In this paper, we focus our attention on data availability by proposing a distributed allocation strategy which takes into account both the privacy policies defined on the contents an…