2023
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Feature-rich networks: when topology meets semantics
Citraro SA network can be enriched with attributes that embed extra information into the nodes. A network can even be enriched with information that encodes different layers of links or that tracks a topological evolution as time goes by. A recent unifying term, that of feature-rich networks, aims to keep all these aspects together within a common denomination and towards a common framework of analysis. The scope of this thesis is three-fold: i) acknowledge all those models that integrate non-structural information into a complex network topology; ii) define new methods (algorithms and measures) for feature-rich network mining; iii) test such methods on applied case studies among different domains. We overview the most influential featurerich representations for complex networks: Node-attributed, Multi-layer, and Dynamic models. All of them open many challenges for the improvement of classic complex network tasks, like community detection, synthetic network generation, and measures for capturing networked patterns and behaviors. We question these tasks, and we develop new methods for feature-rich networks. In particular, we propose EVA, a node-attributed community detection algorithm; X-Mark, a node attributed network generator with planted communities; Conformity, for estimating multi-scale mixing patterns; and ?-Conformity, an extension of the previous one on dynamic environments. Then, we test the proposed methods on different domain specific applications. In particular, we focus on feature-rich models of cognition and higher-order dynamic social data with semantic annotations on users. Throughout the work, our main focus is to demonstrate that mining augmented network topologies can provide novel insights in many domains, and that methods for feature-rich networks can unearth patterns that are invisible to structural-only and semantic only data mining.Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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CNR IRIS
| CNR IRIS
2020
Conference article
Open Access
Eva: attribute-aware network segmentation
Citraro S, Rossetti GIdentifying topologically well-defined communities that are also homogeneous w.r.t. attributes carried by the nodes that compose them is a challenging social network analysis task. We address such a problem by introducing Eva, a bottom-up low complexity algorithm designed to identify network hidden mesoscale topologies by optimizing structural and attribute-homophilic clustering criteria. We evaluate the proposed approach on heterogeneous real-world labeled network datasets, such as co-citation, linguistic, and social networks, and compare it with state-of-art community discovery competitors. Experimental results underline that Eva ensures that network nodes are grouped into communities according to their attribute similarity without considerably degrading partition modularity, both in single and multi node-attribute scenarios.Source: STUDIES IN COMPUTATIONAL INTELLIGENCE (PRINT), pp. 141-151. Lisbon, Portugal, 10-12/12/2019
Project(s): SoBigData ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2019
Conference article
Open Access
A complex network approach to semantic spaces: How meaning organizes itself
Citraro S, Rossetti GWe propose a complex network approach to the emergence of word meaning through the analysis of semantic spaces: NLP techniques able to capture an aspect of meaning based on distributional semantic theories, so that words are linked to each other if they can be substituted in the same linguistic contexts, forming clusters representing semantic fields. This approach can be used to model a mental lexicon of word similarities: a graph G = (N, L) where N are words connected by some type of semantic or associative property L. Networks extracted from a baseline neural language model are analyzed in terms of global properties: they are small world and the probability of degree distribution follows a truncated power law. Moreover, they throw in a strong degree assortativity, a peculiarity that introduces us to the problem of semantic field identification. We support the idea that semantic fields can be identified exploiting the topological information of networks. Several community discovery methods have been tested, identifying from time to time strict semantic fields as crisp communities, linguistic contexts as overlapping communities or meaning conveyed by single words as communities produced starting from a seed-set expansion.Source: CEUR WORKSHOP PROCEEDINGS, vol. 2400. Castiglione Della Pescaia (GR), 19-19/6/2019
Project(s): SoBigData ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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ceur-ws.org
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2020
Journal article
Open Access
Identifying and exploiting homogeneous communities in labeled networks
Citraro S, Rossetti GAttribute-aware community discovery aims to find well-connected communities that are also homogeneous w.r.t. the labels carried by the nodes. In this work, we address such a challenging task presenting Eva, an algorithmic approach designed to maximize a quality function tailoring both structural and homophilic clustering criteria. We evaluate Eva on several real-world labeled networks carrying both nominal and ordinal information, and we compare our approach to other classic and attribute-aware algorithms. Our results suggest that Eva is the only method, among the compared ones, able to discover homogeneous clusters without considerably degrading partition modularity.We also investigate two well-defined applicative scenarios to characterize better Eva: i) the clustering of a mental lexicon, i.e., a linguistic network modeling human semantic memory, and (ii) the node label prediction task, namely the problem of inferring the missing label of a node.Source: APPLIED NETWORK SCIENCE, vol. 5
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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appliednetsci.springeropen.com
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2023
Journal article
Open Access
Feature-rich multiplex lexical networks reveal mental strategies of early language learning
Citraro S, Vitevitch Ms, Stella M, Rossetti GKnowledge in the human mind exhibits a dualistic vector/network nature. Modelling words as vectors is key to natural language processing, whereas networks of word associations can map the nature of semantic memory. We reconcile these paradigms--fragmented across linguistics, psychology and computer science--by introducing FEature-Rich MUltiplex LEXical (FERMULEX) networks. This novel framework merges structural similarities in networks and vector features of words, which can be combined or explored independently. Similarities model heterogenous word associations across semantic/syntactic/phonological aspects of knowledge. Words are enriched with multi-dimensional feature embeddings including frequency, age of acquisition, length and polysemy. These aspects enable unprecedented explorations of cognitive knowledge. Through CHILDES data, we use FERMULEX networks to model normative language acquisition by 1000 toddlers between 18 and 30 months. Similarities and embeddings capture word homophily via conformity, which measures assortative mixing via distance and features. Conformity unearths a language kernel of frequent/polysemous/short nouns and verbs key for basic sentence production, supporting recent evidence of children's syntactic constructs emerging at 30 months. This kernel is invisible to network core-detection and feature-only clustering: It emerges from the dual vector/network nature of words. Our quantitative analysis reveals two key strategies in early word learning. Modelling word acquisition as random walks on FERMULEX topology, we highlight non-uniform filling of communicative developmental inventories (CDIs). Biased random walkers lead to accurate (75%), precise (55%) and partially well-recalled (34%) predictions of early word learning in CDIs, providing quantitative support to previous empirical findings and developmental theories.Source: SCIENTIFIC REPORTS, vol. 13 (issue 1)
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2023
Conference article
Open Access
Attributed stream-hypernetwork analysis: homophilic behaviors in pairwise and group political discussions on reddit
Failla A, Citraro S, Rossetti GComplex networks are solid models to describe human behavior. However, most analyses employing them are bounded to observations made on dyadic connectivity, whereas complex human dynamics involve higher-order relations as well. In the last few years, hypergraph models are rising as promising tools to better understand the behavior of social groups. Yet even such higher-order representations ignore the importance of the rich attributes carried by the nodes. In this work we introduce ASH, an Attributed Stream-Hypernetwork framework to model higher-order temporal networks with attributes on nodes. We leverage ASH to study pairwise and group political discussions on the well-known Reddit platform. Our analysis unveils different patterns while looking at either a pairwise or a higher-order structure for the same phenomena. In particular, we find out that Reddit users tend to surround themselves by like-minded peers with respect to their political leaning when online discussions are proxied by pairwise interactions; conversely, such a tendency significantly decreases when considering nodes embedded in higher-order contexts - that often describe heterophilic discussions.Source: STUDIES IN COMPUTATIONAL INTELLIGENCE (INTERNET), pp. 150-161. Palermo, Italy, 08-10/11/2022
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2023
Journal article
Open Access
Hypergraph models of the mental lexicon capture greater information than pairwise networks for predicting language learning
Citraro S, Warnerwillich J, Battiston F, Siew Csq, Rossetti G, Stella MHuman memory is a complex system that works in associative ways: Reading a cue word can lead to the recollection of associated concepts. The network structure of memory recall patterns has been shown to contain insights about a wide variety of cognitive phenomena, including language acquisition. However, most current network approaches use pairwise connections, i.e. links between only two words at a time. This ignores the possibility that more than two concept representations might be simultaneously associated in memory. We overcome this modelling limitation by introducing cognitive hypergraphs as models of human memory. We model memory recall patterns through word associations from the Small World of Words project for N=6003 concepts (Study 1) and for N=497 concepts (Study 2). In each study we represent word associations as either a pairwise network or a hypergraph. By combining psycholinguistic norms and network centrality measures with machine learning, we quantitatively investigate whether there is any benefit to using the hypergraph model over a pairwise network in predicting test-based age of acquisition norms in children up to age 9 years (Study 1) or normative learning in toddlers up to age 30 months (Study 2, based on CHILDES data). We show that cognitive hypergraphs capture more information than pairwise networks from the same data: Cognitive hypergraphs are considerably more powerful than pairwise networks at predicting age of acquisition trends in toddlers, children and teenagers. Our studies showcase how novel approaches merging artificial intelligence and higher-order interactions can help us understand cognitive development.Source: NEW IDEAS IN PSYCHOLOGY, vol. 71
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2023
Journal article
Open Access
Towards hypergraph cognitive networks as feature-rich models of knowledge
Citraro S, De Deyne S, Stella M, Rossetti GConceptual associations influence how human memory is structured: Cognitive research indicates that similar concepts tend to be recalled one after another. Semantic network accounts provide a useful tool to understand how related concepts are retrieved from memory. However, most current network approaches use pairwise links to represent memory recall patterns (e.g. reading "airplane" makes one think of "air " and "pollution", and this is represented by links "airplane"-"air" and "airplane"-"pollution"). Pairwise connections neglect higher-order associations, i.e. relationships between more than two concepts at a time. These higher-order interactions might covariate with (and thus contain information about) how similar concepts are along psycholinguistic dimensions like arousal, valence, familiarity, gender and others. We overcome these limits by introducing feature-rich cognitive hypergraphs as quantitative models of human memory where: (i) concepts recalled together can all engage in hyperlinks involving also more than two concepts at once (cognitive hypergraph aspect), and (ii) each concept is endowed with a vector of psycholinguistic features (feature-rich aspect). We build hypergraphs from word association data and use evaluation methods from machine learning features to predict concept concreteness. Since concepts with similar concreteness tend to cluster together in human memory, we expect to be able to leverage this structure. Using word association data from the Small World of Words dataset, we compared a pairwise network and a hypergraph with N = 3586 concepts/nodes. Interpretable artificial intelligence models trained on (1) psycholinguistic features only, (2) pairwise-based feature aggregations, and on (3) hypergraph-based aggregations show significant differences between pairwise and hypergraph links. Specifically, our results show that higher-order and feature-rich hypergraph models contain richer information than pairwise networks leading to improved prediction of word concreteness. The relation with previous studies about conceptual clustering and compartmentalisation in associative knowledge and human memory are discussed.Source: EPJ DATA SCIENCE, vol. 12 (issue 1)
Project(s): SoBigData.it – Strengthening the Italian RI for Social Mining and Big Data Analytics
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epjdatascience.springeropen.com
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2023
Journal article
Open Access
Cognitive network science reveals bias in GPT-3, GPT-3.5 turbo, and GPT-4 mirroring math anxiety in high-school students
Abramski K, Citraro S, Lombardi L, Rossetti G, Stella MLarge Language Models (LLMs) are becoming increasingly integrated into our lives. Hence, it is important to understand the biases present in their outputs in order to avoid perpetuating harmful stereotypes, which originate in our own flawed ways of thinking. This challenge requires developing new benchmarks and methods for quantifying affective and semantic bias, keeping in mind that LLMs act as psycho-social mirrors that reflect the views and tendencies that are prevalent in society. One such tendency that has harmful negative effects is the global phenomenon of anxiety toward math and STEM subjects. In this study, we introduce a novel application of network science and cognitive psychology to understand biases towards math and STEM fields in LLMs from ChatGPT, such as GPT-3, GPT-3.5, and GPT-4. Specifically, we use behavioral forma mentis networks (BFMNs) to understand how these LLMs frame math and STEM disciplines in relation to other concepts. We use data obtained by probing the three LLMs in a language generation task that has previously been applied to humans. Our findings indicate that LLMs have negative perceptions of math and STEM fields, associating math with negative concepts in 6 cases out of 10. We observe significant differences across OpenAI's models: newer versions (i.e., GPT-4) produce 5× semantically richer, more emotionally polarized perceptions with fewer negative associations compared to older versions and N=159 high-school students. These findings suggest that advances in the architecture of LLMs may lead to increasingly less biased models that could even perhaps someday aid in reducing harmful stereotypes in society rather than perpetuating them.Source: BIG DATA AND COGNITIVE COMPUTING, vol. 7 (issue 3)
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2024
Journal article
Open Access
Cognitive modelling of concepts in the mental lexicon with multilayer networks: Insights, advancements, and future challenges
Stella M., Citraro S., Rossetti G., Marinazzo D., Kenett Y. N., Vitevitch M. S.The mental lexicon is a complex cognitive system representing information about the words/concepts that one knows. Over decades psychological experiments have shown that conceptual associations across multiple, interactive cognitive levels can greatly influence word acquisition, storage, and processing. How can semantic, phonological, syntactic, and other types of conceptual associations be mapped within a coherent mathematical framework to study how the mental lexicon works? Here we review cognitive multilayer networks as a promising quantitative and interpretative framework for investigating the mental lexicon. Cognitive multilayer networks can map multiple types of information at once, thus capturing how different layers of associations might co-exist within the mental lexicon and influence cognitive processing. This review starts with a gentle introduction to the structure and formalism of multilayer networks. We then discuss quantitative mechanisms of psychological phenomena that could not be observed in single-layer networks and were only unveiled by combining multiple layers of the lexicon: (i) multiplex viability highlights language kernels and facilitative effects of knowledge processing in healthy and clinical populations; (ii) multilayer community detection enables contextual meaning reconstruction depending on psycholinguistic features; (iii) layer analysis can mediate latent interactions of mediation, suppression, and facilitation for lexical access. By outlining novel quantitative perspectives where multilayer networks can shed light on cognitive knowledge representations, including in next-generation brain/mind models, we discuss key limitations and promising directions for cutting-edge future research.Source: PSYCHONOMIC BULLETIN & REVIEW, vol. 31, pp. 1981-2004
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2020
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UTLDR: an agent-based framework for modeling infectious diseases and public interventions
Rossetti G, Milli L, Citraro S, Morini VNowadays, due to the SARS-CoV-2 pandemic, epidemic modelling is experiencing a constantly growing interest from researchers of heterogeneous fields of study. Indeed, the vast literature on computational epidemiology offers solid grounds for analytical studies and the definition of novel models aimed at both predictive and prescriptive scenario descriptions. To ease the access to diffusion modelling, several programming libraries and tools have been proposed during the last decade: however, to the best of our knowledge, none of them is explicitly designed to allow its users to integrate public interventions in their model. In this work, we introduce UTLDR, a framework that can simulate the effects of several public interventions (and their combinations) on the unfolding of epidemic processes. UTLDR enables the design of compartmental models incrementally and to simulate them over complex interaction network topologies. Moreover, it allows integrating external information on the analyzed population (e.g., age, gender, geographical allocation, and mobility patterns. . . ) and to use it to stratify and refine the designed model. After introducing the framework, we provide a few case studies to underline its flexibility and expressive power.Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2020
Other
Open Access
Conformity: A Path-Aware Homophily Measure for Node-Attributed Networks
Rossetti G, Citraro S, Milli LUnveil the homophilic/heterophilic behaviors that characterize the wiring patterns of complex networks is an important task in social network analysis, often approached studying the assortative mixing of node attributes. Recent works underlined that a global measure to quantify node homophily necessarily provides a partial, often deceiving, picture of the reality. Moving from such literature, in this work, we propose a novel measure, namely Conformity, designed to overcome such limitation by providing a node-centric quantification of assortative mixing patterns. Differently from the measures proposed so far, Conformity is designed to be path-aware, thus allowing for a more detailed evaluation of the impact that nodes at different degrees of separations have on the homophilic embeddedness of a target. Experimental analysis on synthetic and real data allowed us to observe that Conformity can unveil valuable insights from node-attributed graphs.Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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arxiv.org
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2021
Journal article
Open Access
Conformity: a Path-Aware Homophily Measure for Node-Attributed Networks
Rossetti G, Citraro S, Milli LUnveiling the homophilic/heterophilic behaviors that characterize the wiring patterns of complex networks is an important task in social network analysis, often approached studying the assortative mixing of node attributes. Recent works have underlined that a global measure to quantify node homophily necessarily provides a partial, often deceiving, picture of the reality. Moving from such literature, in this work, we propose a novel measure, namely Conformity, designed to overcome such limitation by providing a node-centric quantification of assortative mixing patterns. Different from the measures proposed so far, Conformity is designed to be path-aware, thus allowing for a more detailed evaluation of the impact that nodes at different degrees of separations have on the homophilic embeddedness of a target. Experimental analysis on synthetic and real data allowed us to observe that Conformity can unveil valuable insights from node-attributed graphs.Source: IEEE INTELLIGENT SYSTEMS, vol. 36 (issue 1), pp. 25-34
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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| ieeexplore.ieee.org
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2021
Journal article
Open Access
UTLDR: an agent-based framework for modeling infectious diseases and public interventions
Rossetti G, Milli L, Citraro S, Morini VDue to the SARS-CoV-2 pandemic, epidemic modeling is now experiencing a constantly growing interest from researchers of heterogeneous study fields. Indeed, due to such an increased attention, several software libraries and scientific tools have been developed to ease the access to epidemic modeling. However, only a handful of such resources were designed with the aim of providing a simple proxy for the study of the potential effects of public interventions (e.g., lockdown, testing, contact tracing). In this work, we introduce UTLDR, a framework that, overcoming such limitations, allows to generate "what if" epidemic scenarios incorporating several public interventions (and their combinations). UTLDR is designed to be easy to use and capable to leverage information provided by stratified populations of agents (e.g., age, gender, geographical allocation, and mobility patterns...). Moreover, the proposed framework is generic and not tailored for a specific epidemic phenomena: it aims to provide a qualitative support to understanding the effects of restrictions, rather than produce forecasts/explanation of specific data-driven phenomena.Source: JOURNAL OF INTELLIGENT INFORMATION SYSTEMS
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2022
Journal article
Open Access
Delta-Conformity: multi-scale node assortativity in feature-rich stream graphs
Citraro S, Milli L, Cazabet R, Rossetti GMulti-scale strategies to estimate mixing patterns are meant to capture heterogeneous behaviors among node homophily, but they ignore an important addendum often available in real-world networks: the time when edges are present and the timevarying paths that edges form accordingly. In this work, we go beyond the assumption of a static network topology to propose a multi-scale, path- and time-aware node homophily estimator specifically tied for feature-rich stream graphs: Delta-Conformity. Our measure can capture the homogeneous/heterogeneous tendency of nodes' connectivity along a period of time Delta starting from a given moment in time. Results on face-to-face interaction networks suggest it is possible to track changes in social mixing behaviors that coincide with contextually reasonable everyday patterns, e.g., medical staff disassortative behavior when exposed to patients. In a different domain, that of the Bitcoin Transaction Network, we capture relationships between the quantity of money sent from (and to) different categories/continents and their respective mixing trends over time. All these insights help us to introduce Delta-Conformity as a suitable solution for understanding temporal homophily by capturing the mixing tendency of entities embedded in fine-grained evolving contexts.Source: INTERNATIONAL JOURNAL OF DATA SCIENCE AND ANALYTICS, vol. 17, pp. 153-164
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2023
Journal article
Open Access
Cognitive network neighborhoods quantify feelings expressed in suicide notes and Reddit mental health communities
Joseph Sm, Citraro S, Morini V, Rossetti G, Stella MWriting messages is key to expressing feelings. This study adopts cognitive network science to reconstruct how individuals report their feelings in clinical narratives like suicide notes or mental health posts. We achieve this by reconstructing syntactic/semantic associations between concepts in texts as co-occurrences enriched with affective data. We transform 142 suicide notes and 77,000 Reddit posts from the r/anxiety, r/depression, r/schizophrenia, and r/do-it-your-own (r/DIY) forums into 5 cognitive networks, each one expressing meanings and emotions as reported by authors. These networks reconstruct the semantic frames surrounding "feel", stem for "to feel" and "feelings", enabling a quantification of prominent associations and emotions focused around feelings. We find strong feelings of sadness across all clinical Reddit boards, added to fear r/depression, and replaced by joy/anticipation in r/DIY. Semantic communities and topic modeling both highlight key narrative topics of "regret", "unhealthy lifestyle" and "low mental well-being". Importantly, negative associations and emotions co-existed with trustful/positive language, focused on "getting better". This emotional polarization provides quantitative evidence that online clinical boards possess a complex structure, where users mix both positive and negative outlooks. This dichotomy is absent in the DIY reference board and in suicide notes, where negative emotional associations about regret and pain persist but are overwhelmed by positive jargon addressing loved ones. Our network-based comparisons provide quantitative evidence that suicide notes encapsulate different ways of expressing feelings compared to online Reddit boards, the latter acting more like personal diaries and relief valves. Our findings provide an interpretable network-based aid for supporting psychological inquiries of human feelings in digital and clinical settings.Source: PHYSICA. A, vol. 610 (issue 128336)
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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2023
Journal article
Open Access
Attributed stream hypergraphs: temporal modeling of node-attributed high-order interactions
Failla A, Citraro S, Rossetti GRecent advances in network science have resulted in two distinct research directions aimed at augmenting and enhancing representations for complex networks. The first direction, that of high-order modeling, aims to focus on connectivity between sets of nodes rather than pairs, whereas the second one, that of feature-rich augmentation, incorporates into a network all those elements that are driven by information which is external to the structure, like node properties or the flow of time. This paper proposes a novel toolbox, that of Attributed Stream Hypergraphs (ASHs), unifying both high-order and feature-rich elements for representing, mining, and analyzing complex networks. Applied to social network analysis, ASHs can characterize complex social phenomena along topological, dynamic and attributive elements. Experiments on real-world face-to-face and online social media interactions highlight that ASHs can easily allow for the analyses, among others, of high-order groups' homophily, nodes' homophily with respect to the hyperedges in which nodes participate, and time-respecting paths between hyperedges.Source: APPLIED NETWORK SCIENCE, vol. 8 (issue 1)
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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appliednetsci.springeropen.com
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2024
Journal article
Open Access
Describing group evolution in temporal data using multi-faceted events
Failla A, Cazabet R., Rossetti G., Citraro S.Groups—such as clusters of points or communities of nodes—are fundamental when addressing various data mining tasks. In temporal data, the predominant approach for characterizing group evolution has been through the identification of “events”. However, the events usually described in the literature, e.g., shrinks/growths, splits/merges, are often arbitrarily defined, creating a gap between such theoretical/predefined types and real-data group observations. Moving beyond existing taxonomies, we think of events as “archetypes” characterized by a unique combination of quantitative dimensions that we call “facets”. Group dynamics are defined by their position within the facet space, where archetypal events occupy extremities. Thus, rather than enforcing strict event types, our approach can allow for hybrid descriptions of dynamics involving group proximity to multiple archetypes. We apply our framework to evolving groups from several face-to-face interaction datasets, showing it enables richer, more reliable characterization of group dynamics with respect to state-of-the-art methods, especially when the groups are subject to complex relationships. Our approach also offers intuitive solutions to common tasks related to dynamic group analysis, such as choosing an appropriate aggregation scale, quantifying partition stability, and evaluating event quality.Source: MACHINE LEARNING, vol. 113 (issue 10), pp. 7591-7615
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2024
Journal article
Open Access
Online posting effects: unveiling the non-linear journeys of users in depression communities on Reddit
Morini V., Citraro S., Sajno E., Sansoni M., Riva G., Stella M., Rossetti G.Social media platforms have become pivotal as self-help forums, enabling individuals to share personal experiences and seek support. However, on topics as sensitive as depression, what are the consequences of online self-disclosure? Here, we delve into the dynamics of mental health discourse on various Reddit boards focused on depression. To this aim, we introduce a data-informed framework reconstructing online dynamics from 303k users interacting over two years. Through user-generated content, we identify 4 distinct clusters representing different psychological states. Our analysis unveils online posting effects: a user can transition to another psychological state after online exposure to peers’ emotional/semantic content. As described by conditional Markov chains and different levels of social exposure, users’ transitions reveal navigation through both positive and negative phases in a spiral rather than a linear progression. Interpreted in light of psychological literature, related particularly to the Patient Health Engagement (PHE) model, our findings can provide evidence that the type and layout of online social interactions have an impact on users’ “journeys” when posting about depression.Source: COMPUTERS IN HUMAN BEHAVIOR REPORTS, vol. 17 (issue 100542 (n. articolo))
Project(s): SoBigData-PlusPlus ![via OpenAIRE](/components/com_dnetindexclient/img/openaire_logo.png)
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