baldassarri baronchelli barrat caglioti castellano cattuto complexity dattoli evolutionary_dynamics granular_media granular_media herrmann information_theory innovation_dynamics kreyon language_dynamics loreto mari mukherjee petri pietronero puglisi quantum_optics self_organization servedio statistical_physics techno_social_systems tria zapperi zippers
2016 |
V Loreto VDP Servedio, SH Strogatz Tria F Dynamics on Expanding Spaces: Modeling the Emergence of Novelties Book Chapter Mirko Degli Esposti Eduardo G. Altmann, François Pachet (Ed.): Creativity and Universality in Language, pp. 59-83, Springer International Publishing, 2016, ISBN: 978-3-319-24401-3. Abstract | Links | BibTeX | Tag: adjacent possible, innovation_dynamics, kreyon, loreto, review, servedio, strogatz, tria @inbook{Loreto2016, title = {Dynamics on Expanding Spaces: Modeling the Emergence of Novelties}, author = {V Loreto, VDP Servedio, SH Strogatz, F Tria}, editor = {Mirko Degli Esposti, Eduardo G. Altmann, François Pachet}, url = {http://link.springer.com/chapter/10.1007%2F978-3-319-24403-7_5}, doi = {10.1007/978-3-319-24403-7_5}, isbn = {978-3-319-24401-3}, year = {2016}, date = {2016-05-19}, booktitle = {Creativity and Universality in Language}, pages = {59-83}, publisher = {Springer International Publishing}, series = {Lecture Notes in Morphogenesis}, abstract = {Novelties are part of our daily lives. We constantly adopt new technologies, conceive new ideas, meet new people, and experiment with new situations. Occasionally, we as individual, in a complicated cognitive and sometimes fortuitous process, come up with something that is not only new to us, but to our entire society so that what is a personal novelty can turn into an innovation at a global level. Innovations occur throughout social, biological, and technological systems and, though we perceive them as a very natural ingredient of our human experience, little is known about the processes determining their emergence. Still the statistical occurrence of innovations shows striking regularities that represent a starting point to get a deeper insight in the whole phenomenology. This paper represents a small step in that direction, focusing on reviewing the scientific attempts to effectively model the emergence of the new and its regularities, with an emphasis on more recent contributions: from the plain Simon’s model tracing back to the 1950s, to the newest model of Polya’s urn with triggering of one novelty by another. What seems to be key in the successful modeling schemes proposed so far is the idea of looking at evolution as a path in a complex space, physical, conceptual, biological, and technological, whose structure and topology get continuously reshaped and expanded by the occurrence of the new. Mathematically, it is very interesting to look at the consequences of the interplay between the “actual” and the “possible” and this is the aim of this short review.}, keywords = {adjacent possible, innovation_dynamics, kreyon, loreto, review, servedio, strogatz, tria}, pubstate = {published}, tppubtype = {inbook} } Novelties are part of our daily lives. We constantly adopt new technologies, conceive new ideas, meet new people, and experiment with new situations. Occasionally, we as individual, in a complicated cognitive and sometimes fortuitous process, come up with something that is not only new to us, but to our entire society so that what is a personal novelty can turn into an innovation at a global level. Innovations occur throughout social, biological, and technological systems and, though we perceive them as a very natural ingredient of our human experience, little is known about the processes determining their emergence. Still the statistical occurrence of innovations shows striking regularities that represent a starting point to get a deeper insight in the whole phenomenology. This paper represents a small step in that direction, focusing on reviewing the scientific attempts to effectively model the emergence of the new and its regularities, with an emphasis on more recent contributions: from the plain Simon’s model tracing back to the 1950s, to the newest model of Polya’s urn with triggering of one novelty by another. What seems to be key in the successful modeling schemes proposed so far is the idea of looking at evolution as a path in a complex space, physical, conceptual, biological, and technological, whose structure and topology get continuously reshaped and expanded by the occurrence of the new. Mathematically, it is very interesting to look at the consequences of the interplay between the “actual” and the “possible” and this is the aim of this short review. |
Tria, Francesca; Loreto, Vittorio; Servedio, Vito; Salikoko, Mufwene S Modeling The Emergence Of Creole Languages Inproceedings Roberts, S G; Cuskley, C; McCrohon, L; Barceló-Coblijn, L; Fehér, O; Verhoef, T (Ed.): The Evolution of Language: Proceedings of the 11th International Conference (EVOLANGX11), 2016. Abstract | Links | BibTeX | Tag: kreyon, language_dynamics, language_games, loreto, servedio, tria @inproceedings{evolang11_89, title = {Modeling The Emergence Of Creole Languages}, author = {Francesca Tria and Vittorio Loreto and Vito Servedio and S. Mufwene Salikoko}, editor = {S.G. Roberts and C. Cuskley and L. McCrohon and L. Barceló-Coblijn and O. Fehér and T. Verhoef}, url = {http://evolang.org/neworleans/papers/89.html}, year = {2016}, date = {2016-01-01}, booktitle = {The Evolution of Language: Proceedings of the 11th International Conference (EVOLANGX11)}, abstract = {Creole languages offer an invaluable opportunity to study the processes leading to the emergence and evolution of Language, thanks to the short - typically a few generations - and reasonably well defined time-scales involved in their emergence. Another well-known case of a very fast emergence of a Language, though referring to a much smaller population size and different ecological conditions, is that of the Nicaraguan Sign Language. What these two phenomena have in common is that in both cases what is emerging is a contact language, i.e., a language born out of the non-trivial interaction of two (or more) parent languages. This is a typical case of what is known in biology as horizontal transmission. In many well-documented cases, creoles emerged in large segregated sugarcane or rice plantations on which the slave labourers were the overwhelming majority. Lacking a common substrate language, slaves were naturally brought to shift to the economically and politically dominant European language (often referred to as the lexifier) to bootstrap an effective communication system among themselves. Here, we focus on the emergence of creole languages originated in the contacts of European colonists and slaves during the 17th and 18th centuries in exogenous plantation colonies of especially the Atlantic and Indian Ocean, where detailed census data are available. Those for several States of USA can be found at http://www.census.gov/history, while for Central America and the Caribbean can be found at http://www.jamaicanfamilysearch.com/Samples/1790al11.htm. Without entering in the details of the creole formation at a fine-grained linguistic level, we aim at uncovering some of the general mechanisms that determine the emergence of contact languages, and that successfully apply to the case of creole formation.}, keywords = {kreyon, language_dynamics, language_games, loreto, servedio, tria}, pubstate = {published}, tppubtype = {inproceedings} } Creole languages offer an invaluable opportunity to study the processes leading to the emergence and evolution of Language, thanks to the short - typically a few generations - and reasonably well defined time-scales involved in their emergence. Another well-known case of a very fast emergence of a Language, though referring to a much smaller population size and different ecological conditions, is that of the Nicaraguan Sign Language. What these two phenomena have in common is that in both cases what is emerging is a contact language, i.e., a language born out of the non-trivial interaction of two (or more) parent languages. This is a typical case of what is known in biology as horizontal transmission. In many well-documented cases, creoles emerged in large segregated sugarcane or rice plantations on which the slave labourers were the overwhelming majority. Lacking a common substrate language, slaves were naturally brought to shift to the economically and politically dominant European language (often referred to as the lexifier) to bootstrap an effective communication system among themselves. Here, we focus on the emergence of creole languages originated in the contacts of European colonists and slaves during the 17th and 18th centuries in exogenous plantation colonies of especially the Atlantic and Indian Ocean, where detailed census data are available. Those for several States of USA can be found at http://www.census.gov/history, while for Central America and the Caribbean can be found at http://www.jamaicanfamilysearch.com/Samples/1790al11.htm. Without entering in the details of the creole formation at a fine-grained linguistic level, we aim at uncovering some of the general mechanisms that determine the emergence of contact languages, and that successfully apply to the case of creole formation. |
2015 |
Mastroianni, Pierpaolo; Monechi, Bernardo; Liberto, Carlo; Valenti, Gaetano; Servedio, Vito DP; Loreto, Vittorio Local Optimization Strategies in Urban Vehicular Mobility Journal Article PloS one, 10 (12), pp. e0143799, 2015. Abstract | Links | BibTeX | Tag: GPS data, human mobility, kreyon, local optimization, loreto, monechi, servedio, urban network @article{Mastroianni2015, title = {Local Optimization Strategies in Urban Vehicular Mobility}, author = {Pierpaolo Mastroianni and Bernardo Monechi and Carlo Liberto and Gaetano Valenti and Vito DP Servedio and Vittorio Loreto}, url = {http://journals.plos.org/plosone/article?id=10.1371%2Fjournal.pone.0143799}, doi = {doi:10.1371/journal.pone.0143799}, year = {2015}, date = {2015-12-15}, journal = {PloS one}, volume = {10}, number = {12}, pages = {e0143799}, publisher = {Public Library of Science}, abstract = {The comprehension of vehicular traffic in urban environments is crucial to achieve a good management of the complex processes arising from people collective motion. Even allowing for the great complexity of human beings, human behavior turns out to be subject to strong constraints—physical, environmental, social, economic—that induce the emergence of common patterns. The observation and understanding of those patterns is key to setup effective strategies to optimize the quality of life in cities while not frustrating the natural need for mobility. In this paper we focus on vehicular mobility with the aim to reveal the underlying patterns and uncover the human strategies determining them. To this end we analyze a large dataset of GPS vehicles tracks collected in the Rome (Italy) district during a month. We demonstrate the existence of a local optimization of travel times that vehicle drivers perform while choosing their journey. This finding is mirrored by two additional important facts, i.e., the observation that the average vehicle velocity increases by increasing the travel length and the emergence of a universal scaling law for the distribution of travel times at fixed traveled length. A simple modeling scheme confirms this scenario opening the way to further predictions.}, keywords = {GPS data, human mobility, kreyon, local optimization, loreto, monechi, servedio, urban network}, pubstate = {published}, tppubtype = {article} } The comprehension of vehicular traffic in urban environments is crucial to achieve a good management of the complex processes arising from people collective motion. Even allowing for the great complexity of human beings, human behavior turns out to be subject to strong constraints—physical, environmental, social, economic—that induce the emergence of common patterns. The observation and understanding of those patterns is key to setup effective strategies to optimize the quality of life in cities while not frustrating the natural need for mobility. In this paper we focus on vehicular mobility with the aim to reveal the underlying patterns and uncover the human strategies determining them. To this end we analyze a large dataset of GPS vehicles tracks collected in the Rome (Italy) district during a month. We demonstrate the existence of a local optimization of travel times that vehicle drivers perform while choosing their journey. This finding is mirrored by two additional important facts, i.e., the observation that the average vehicle velocity increases by increasing the travel length and the emergence of a universal scaling law for the distribution of travel times at fixed traveled length. A simple modeling scheme confirms this scenario opening the way to further predictions. |
Rodi, Giovanna Chiara; Loreto, Vittorio; Servedio, Vito DP; Tria, Francesca Optimal Learning Paths in Information Networks Journal Article Scientific Reports, 5 (10286), 2015. Abstract | Links | BibTeX | Tag: innovation_dynamics, kreyon, learning_dynamics, loreto, rodi, servedio, tria @article{Rodi2015, title = {Optimal Learning Paths in Information Networks}, author = {Giovanna Chiara Rodi and Vittorio Loreto and Vito DP Servedio and Francesca Tria}, url = {http://www.nature.com/srep/2015/150601/srep10286/full/srep10286.html}, doi = {10.1038/srep10286}, year = {2015}, date = {2015-06-01}, journal = {Scientific Reports}, volume = {5}, number = {10286}, abstract = {Each sphere of knowledge and information could be depicted as a complex mesh of correlated items. By properly exploiting these connections, innovative and more efficient navigation strategies could be defined, possibly leading to a faster learning process and an enduring retention of information. In this work we investigate how the topological structure embedding the items to be learned can affect the efficiency of the learning dynamics. To this end we introduce a general class of algorithms that simulate the exploration of knowledge/information networks standing on well-established findings on educational scheduling, namely the spacing and lag effects. While constructing their learning schedules, individuals move along connections, periodically revisiting some concepts, and sometimes jumping on very distant ones. In order to investigate the effect of networked information structures on the proposed learning dynamics we focused both on synthetic and real-world graphs such as subsections of Wikipedia and word-association graphs. We highlight the existence of optimal topological structures for the simulated learning dynamics whose efficiency is affected by the balance between hubs and the least connected items. Interestingly, the real-world graphs we considered lead naturally to almost optimal learning performances.}, keywords = {innovation_dynamics, kreyon, learning_dynamics, loreto, rodi, servedio, tria}, pubstate = {published}, tppubtype = {article} } Each sphere of knowledge and information could be depicted as a complex mesh of correlated items. By properly exploiting these connections, innovative and more efficient navigation strategies could be defined, possibly leading to a faster learning process and an enduring retention of information. In this work we investigate how the topological structure embedding the items to be learned can affect the efficiency of the learning dynamics. To this end we introduce a general class of algorithms that simulate the exploration of knowledge/information networks standing on well-established findings on educational scheduling, namely the spacing and lag effects. While constructing their learning schedules, individuals move along connections, periodically revisiting some concepts, and sometimes jumping on very distant ones. In order to investigate the effect of networked information structures on the proposed learning dynamics we focused both on synthetic and real-world graphs such as subsections of Wikipedia and word-association graphs. We highlight the existence of optimal topological structures for the simulated learning dynamics whose efficiency is affected by the balance between hubs and the least connected items. Interestingly, the real-world graphs we considered lead naturally to almost optimal learning performances. |
Bernardo Monechi, Vito DP Servedio ; Loreto, Vittorio Congestion Transition in Air Traffic Networks Journal Article PLoS ONE, 10 (5), pp. e0125546, 2015. Abstract | Links | BibTeX | Tag: air traffic, complex_systems, loreto, monechi, servedio, transportation networks @article{Monechi2015, title = {Congestion Transition in Air Traffic Networks}, author = {Bernardo Monechi, Vito DP Servedio and Vittorio Loreto}, url = {http://dx.doi.org/10.1371%2Fjournal.pone.0125546}, doi = {10.1371/journal.pone.0125546}, year = {2015}, date = {2015-05-20}, journal = {PLoS ONE}, volume = {10}, number = {5}, pages = {e0125546}, abstract = {Air Transportation represents a very interesting example of a complex techno-social system whose importance has considerably grown in time and whose management requires a careful understanding of the subtle interplay between technological infrastructure and human behavior. Despite the competition with other transportation systems, a growth of air traffic is still foreseen in Europe for the next years. The increase of traffic load could bring the current Air Traffic Network above its capacity limits so that safety standards and performances might not be guaranteed anymore. Lacking the possibility of a direct investigation of this scenario, we resort to computer simulations in order to quantify the disruptive potential of an increase in traffic load. To this end we model the Air Transportation system as a complex dynamical network of flights controlled by humans who have to solve potentially dangerous conflicts by redirecting aircraft trajectories. The model is driven and validated through historical data of flight schedules in a European national airspace. While correctly reproducing actual statistics of the Air Transportation system, e.g., the distribution of delays, the model allows for theoretical predictions. Upon an increase of the traffic load injected in the system, the model predicts a transition from a phase in which all conflicts can be successfully resolved, to a phase in which many conflicts cannot be resolved anymore. We highlight how the current flight density of the Air Transportation system is well below the transition, provided that controllers make use of a special re-routing procedure. While the congestion transition displays a universal scaling behavior, its threshold depends on the conflict solving strategy adopted. Finally, the generality of the modeling scheme introduced makes it a flexible general tool to simulate and control Air Transportation systems in realistic and synthetic scenarios.}, keywords = {air traffic, complex_systems, loreto, monechi, servedio, transportation networks}, pubstate = {published}, tppubtype = {article} } Air Transportation represents a very interesting example of a complex techno-social system whose importance has considerably grown in time and whose management requires a careful understanding of the subtle interplay between technological infrastructure and human behavior. Despite the competition with other transportation systems, a growth of air traffic is still foreseen in Europe for the next years. The increase of traffic load could bring the current Air Traffic Network above its capacity limits so that safety standards and performances might not be guaranteed anymore. Lacking the possibility of a direct investigation of this scenario, we resort to computer simulations in order to quantify the disruptive potential of an increase in traffic load. To this end we model the Air Transportation system as a complex dynamical network of flights controlled by humans who have to solve potentially dangerous conflicts by redirecting aircraft trajectories. The model is driven and validated through historical data of flight schedules in a European national airspace. While correctly reproducing actual statistics of the Air Transportation system, e.g., the distribution of delays, the model allows for theoretical predictions. Upon an increase of the traffic load injected in the system, the model predicts a transition from a phase in which all conflicts can be successfully resolved, to a phase in which many conflicts cannot be resolved anymore. We highlight how the current flight density of the Air Transportation system is well below the transition, provided that controllers make use of a special re-routing procedure. While the congestion transition displays a universal scaling behavior, its threshold depends on the conflict solving strategy adopted. Finally, the generality of the modeling scheme introduced makes it a flexible general tool to simulate and control Air Transportation systems in realistic and synthetic scenarios. |
Tria, Francesca; Servedio, Vito D P; Mufwene, Salikoko; Loreto, Vittorio Modeling the Emergence of Contact Languages Journal Article PLoS ONE, 10 (4), pp. e0120771, 2015. Abstract | Links | BibTeX | Tag: creoles, kreyon, language_dynamics, language_games, loreto, servedio, tria @article{10.1371/journal.pone.0120771, title = {Modeling the Emergence of Contact Languages}, author = {Francesca Tria and Vito D.P. Servedio and Salikoko Mufwene and Vittorio Loreto}, url = {http://dx.doi.org/10.1371%2Fjournal.pone.0120771}, doi = {10.1371/journal.pone.0120771}, year = {2015}, date = {2015-01-01}, journal = {PLoS ONE}, volume = {10}, number = {4}, pages = {e0120771}, publisher = {Public Library of Science}, abstract = { Contact languages are born out of the non-trivial interaction of two (or more) parent languages. Nowadays, the enhanced possibility of mobility and communication allows for a strong mixing of languages and cultures, thus raising the issue of whether there are any pure languages or cultures that are unaffected by contact with others. As with bacteria or viruses in biological evolution, the evolution of languages is marked by horizontal transmission; but to date no reliable quantitative tools to investigate these phenomena have been available. An interesting and well documented example of contact language is the emergence of creole languages, which originated in the contacts of European colonists and slaves during the 17th and 18th centuries in exogenous plantation colonies of especially the Atlantic and Indian Ocean. Here, we focus on the emergence of creole languages to demonstrate a dynamical process that mimics the process of creole formation in American and Caribbean plantation ecologies. Inspired by the Naming Game (NG), our modeling scheme incorporates demographic information about the colonial population in the framework of a non-trivial interaction network including three populations: Europeans, Mulattos/Creoles, and Bozal slaves. We show how this sole information makes it possible to discriminate territories that produced modern creoles from those that did not, with a surprising accuracy. The generality of our approach provides valuable insights for further studies on the emergence of languages in contact ecologies as well as to test specific hypotheses about the peopling and the population structures of the relevant territories. We submit that these tools could be relevant to addressing problems related to contact phenomena in many cultural domains: e.g., emergence of dialects, language competition and hybridization, globalization phenomena. },keywords = {creoles, kreyon, language_dynamics, language_games, loreto, servedio, tria}, pubstate = {published}, tppubtype = {article} } <p>Contact languages are born out of the non-trivial interaction of two (or more) parent languages. Nowadays, the enhanced possibility of mobility and communication allows for a strong mixing of languages and cultures, thus raising the issue of whether there are any pure languages or cultures that are unaffected by contact with others. As with bacteria or viruses in biological evolution, the evolution of languages is marked by horizontal transmission; but to date no reliable quantitative tools to investigate these phenomena have been available. An interesting and well documented example of contact language is the emergence of creole languages, which originated in the contacts of European colonists and slaves during the 17th and 18th centuries in exogenous plantation colonies of especially the Atlantic and Indian Ocean. Here, we focus on the emergence of creole languages to demonstrate a dynamical process that mimics the process of creole formation in American and Caribbean plantation ecologies. Inspired by the Naming Game (NG), our modeling scheme incorporates demographic information about the colonial population in the framework of a non-trivial interaction network including three populations: Europeans, Mulattos/Creoles, and Bozal slaves. We show how this sole information makes it possible to discriminate territories that produced modern creoles from those that did not, with a surprising accuracy. The generality of our approach provides valuable insights for further studies on the emergence of languages in contact ecologies as well as to test specific hypotheses about the peopling and the population structures of the relevant territories. We submit that these tools could be relevant to addressing problems related to contact phenomena in many cultural domains: e.g., emergence of dialects, language competition and hybridization, globalization phenomena.</p> |
2014 |
Bernardo Monechi Vito DP Servedio, Vittorio Loreto Complex Networks and Transport Systems: Application to Air Transport and Urban Mobility PhD Thesis "Sapienza" University of Rome, 2014. Abstract | Links | BibTeX | Tag: air traffic, big data, complex network, GPS data, human mobility, local optimization, loreto, monechi, servedio, transportation network @phdthesis{MonechiPhDThesis2014, title = {Complex Networks and Transport Systems: Application to Air Transport and Urban Mobility}, author = {Bernardo Monechi, Vito DP Servedio, Vittorio Loreto}, url = {http://www.phys.uniroma1.it/fisica/sites/default/files/DOTT_FISICA/MENU/03DOTTORANDI/TesiFin27/Monechi.pdf}, year = {2014}, date = {2014-12-20}, address = {Piazzale Aldo Moro 5, 00185, Roma (RO), Italy}, school = {"Sapienza" University of Rome}, abstract = {This thesis is devoted to the study of transportation systems by means of Complex Systems and Complex Network Theories. Complex Networks are a tools of inestimable value in human transportation studies since in most of the cases the means of transportation used by individuals to move in space are bounded to move on a complex network. The topological properties of transportation networks can influence both the ability of individuals to move as well as their behavior in the environment, thus a characterization of the network is mandatory in order to understand the properties of the considered system. The two transportation systems that have been studied in this work are the Air Transport System and the mobility of cars in a urban environment. The analysis and modeling of the Air Transport System is the first and most extensive part of this thesis. In particular we will try to characterize and study the networks in which aircraft fly, exploiting these results to build a data-driven model of Air Traffic Control. The second part of the thesis is a continuation of the studies performed during by Pierpaolo Mastroianni during his Master Thesis. His work concerned the analysis of GPS tracks data in the City of Rome and the inference of statistical laws characterizing the behavior of car drivers. My contribution to his work is the development of a model capable of explaining some of the results presented in the Master Thesis.}, keywords = {air traffic, big data, complex network, GPS data, human mobility, local optimization, loreto, monechi, servedio, transportation network}, pubstate = {published}, tppubtype = {phdthesis} } This thesis is devoted to the study of transportation systems by means of Complex Systems and Complex Network Theories. Complex Networks are a tools of inestimable value in human transportation studies since in most of the cases the means of transportation used by individuals to move in space are bounded to move on a complex network. The topological properties of transportation networks can influence both the ability of individuals to move as well as their behavior in the environment, thus a characterization of the network is mandatory in order to understand the properties of the considered system. The two transportation systems that have been studied in this work are the Air Transport System and the mobility of cars in a urban environment. The analysis and modeling of the Air Transport System is the first and most extensive part of this thesis. In particular we will try to characterize and study the networks in which aircraft fly, exploiting these results to build a data-driven model of Air Traffic Control. The second part of the thesis is a continuation of the studies performed during by Pierpaolo Mastroianni during his Master Thesis. His work concerned the analysis of GPS tracks data in the City of Rome and the inference of statistical laws characterizing the behavior of car drivers. My contribution to his work is the development of a model capable of explaining some of the results presented in the Master Thesis. |
Bernardo Monechi Vito DP Servedio, Vittorio Loreto An Air Traffic Control Model Based Local Optimization over the Airways Network Inproceedings Schaefer, Dirk (Ed.): Proceedings of the SESAR Innovation Days (2014), EUROCONTROL 2014, ISBN: 978-2-87497-077-1. Abstract | Links | BibTeX | Tag: air traffic, extremal optimization, local optimization, loreto, monechi, servedio, transportation networks @inproceedings{Monechi2014, title = {An Air Traffic Control Model Based Local Optimization over the Airways Network}, author = {Bernardo Monechi, Vito DP Servedio, Vittorio Loreto}, editor = {Dirk Schaefer}, url = {http://www.sesarinnovationdays.eu/sites/default/files/media/SIDs/SID%202014-04.pdf}, isbn = {978-2-87497-077-1}, year = {2014}, date = {2014-11-25}, booktitle = {Proceedings of the SESAR Innovation Days (2014)}, organization = {EUROCONTROL}, abstract = {The introduction of a new SESAR scenario in the European Airspace will impact the functioning and the performances of the current Air Traffic Management (ATM) System. The understanding of the features and the limits of the current system could be crucial in order to improve and design the structure of the future ATM. In this paper we present some results of the "Assessment of Critical Delay Patterns and Avalanche Dynamics” PhD project from the ComplexWorld Network. During this project we developed a model of Air Traffic Control (ATC) based on Complex Network theory capable of reproducing the features of the real ATC in three European National Airspaces. We then developed an optimization algorithm based on “Extremal Optimization” in order to build efficient and globally optimized planned trajectories. The ATC model is applied in order to study the efficiency of this new planned trajectories when subject to external perturbations and to compare them to the current situation.}, keywords = {air traffic, extremal optimization, local optimization, loreto, monechi, servedio, transportation networks}, pubstate = {published}, tppubtype = {inproceedings} } The introduction of a new SESAR scenario in the European Airspace will impact the functioning and the performances of the current Air Traffic Management (ATM) System. The understanding of the features and the limits of the current system could be crucial in order to improve and design the structure of the future ATM. In this paper we present some results of the "Assessment of Critical Delay Patterns and Avalanche Dynamics” PhD project from the ComplexWorld Network. During this project we developed a model of Air Traffic Control (ATC) based on Complex Network theory capable of reproducing the features of the real ATC in three European National Airspaces. We then developed an optimization algorithm based on “Extremal Optimization” in order to build efficient and globally optimized planned trajectories. The ATC model is applied in order to study the efficiency of this new planned trajectories when subject to external perturbations and to compare them to the current situation. |
Tria, Francesca; Loreto, Vittorio; Servedio, Vito Domenico Pietro; Strogatz, Steven H The dynamics of correlated novelties Journal Article SCIENTIFIC REPORTS, 4 , 2014. Abstract | Links | BibTeX | Tag: innovation_dynamics, loreto, servedio, strogatz, tria @article{b, title = {The dynamics of correlated novelties}, author = {Francesca Tria and Vittorio Loreto and Vito Domenico Pietro Servedio and Steven H. Strogatz}, url = {http://www.nature.com/srep/2014/140731/srep05890/full/srep05890.html}, year = {2014}, date = {2014-01-01}, journal = {SCIENTIFIC REPORTS}, volume = {4}, publisher = {Nature Publishing Group}, abstract = {Novelties are a familiar part of daily life. They are also fundamental to the evolution of biological systems, human society, and technology. By opening new possibilities, one novelty can pave the way for others in a process that Kauffman has called expanding the adjacent possible . The dynamics of correlated novelties, however, have yet to be quantified empirically or modeled mathematically. Here we propose a simple mathematical model that mimics the process of exploring a physical, biological, or conceptual space that enlarges whenever a novelty occurs. The model, a generalization of Polya's urn, predicts statistical laws for the rate at which novelties happen (Heaps' law) and for the probability distribution on the space explored (Zipf's law), as well as signatures of the process by which one novelty sets the stage for another. We test these predictions on four data sets of human activity: the edit events of Wikipedia pages, the emergence of tags in annotation systems, the sequence of words in texts, and listening to new songs in online music catalogues. By quantifying the dynamics of correlated novelties, our results provide a starting point for a deeper understanding of the adjacent possible and its role in biological, cultural, and technological evolution.}, keywords = {innovation_dynamics, loreto, servedio, strogatz, tria}, pubstate = {published}, tppubtype = {article} } Novelties are a familiar part of daily life. They are also fundamental to the evolution of biological systems, human society, and technology. By opening new possibilities, one novelty can pave the way for others in a process that Kauffman has called expanding the adjacent possible . The dynamics of correlated novelties, however, have yet to be quantified empirically or modeled mathematically. Here we propose a simple mathematical model that mimics the process of exploring a physical, biological, or conceptual space that enlarges whenever a novelty occurs. The model, a generalization of Polya's urn, predicts statistical laws for the rate at which novelties happen (Heaps' law) and for the probability distribution on the space explored (Zipf's law), as well as signatures of the process by which one novelty sets the stage for another. We test these predictions on four data sets of human activity: the edit events of Wikipedia pages, the emergence of tags in annotation systems, the sequence of words in texts, and listening to new songs in online music catalogues. By quantifying the dynamics of correlated novelties, our results provide a starting point for a deeper understanding of the adjacent possible and its role in biological, cultural, and technological evolution. |
2013 |
Becker, Martin; Caminiti, Saverio; Fiorella, Donato; Francis, Louise; Gravino, Pietro; Haklay, Mordechai; Hotho, Andreas; Loreto, Vittorio; Mueller, Juergen; Ricchiuti, Ferdinando; Servedio, Vito D P; Sirbu, Alina; Tria, Francesca Awareness and learning in participatory noise sensing Journal Article PLoS ONE, 8 , pp. e81638-1–e81638-12, 2013. Abstract | Links | BibTeX | Tag: citizen_science, loreto, servedio, sirbu, tria @article{b, title = {Awareness and learning in participatory noise sensing}, author = {Martin Becker and Saverio Caminiti and Donato Fiorella and Louise Francis and Pietro Gravino and Mordechai Haklay and Andreas Hotho and Vittorio Loreto and Juergen Mueller and Ferdinando Ricchiuti and Vito D.P. Servedio and Alina Sirbu and Francesca Tria}, url = {http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0081638}, year = {2013}, date = {2013-01-01}, journal = {PLoS ONE}, volume = {8}, pages = {e81638-1--e81638-12}, abstract = {The development of ICT infrastructures has facilitated the emergence of new paradigms for looking at society and the environment over the last few years. Participatory environmental sensing, i.e. directly involving citizens in environmental monitoring, is one example, which is hoped to encourage learning and enhance awareness of environmental issues. In this paper, an analysis of the behaviour of individuals involved in noise sensing is presented. Citizens have been involved in noise measuring activities through the WideNoise smartphone application. This application has been designed to record both objective (noise samples) and subjective (opinions, feelings) data. The application has been open to be used freely by anyone and has been widely employed worldwide. In addition, several test cases have been organised in European countries. Based on the information submitted by users, an analysis of emerging awareness and learning is performed. The data show that changes in the way the environment is perceived after repeated usage of the application do appear. Specifically, users learn how to recognise different noise levels they are exposed to. Additionally, the subjective data collected indicate an increased user involvement in time and a categorisation effect between pleasant and less pleasant environments.}, keywords = {citizen_science, loreto, servedio, sirbu, tria}, pubstate = {published}, tppubtype = {article} } The development of ICT infrastructures has facilitated the emergence of new paradigms for looking at society and the environment over the last few years. Participatory environmental sensing, i.e. directly involving citizens in environmental monitoring, is one example, which is hoped to encourage learning and enhance awareness of environmental issues. In this paper, an analysis of the behaviour of individuals involved in noise sensing is presented. Citizens have been involved in noise measuring activities through the WideNoise smartphone application. This application has been designed to record both objective (noise samples) and subjective (opinions, feelings) data. The application has been open to be used freely by anyone and has been widely employed worldwide. In addition, several test cases have been organised in European countries. Based on the information submitted by users, an analysis of emerging awareness and learning is performed. The data show that changes in the way the environment is perceived after repeated usage of the application do appear. Specifically, users learn how to recognise different noise levels they are exposed to. Additionally, the subjective data collected indicate an increased user involvement in time and a categorisation effect between pleasant and less pleasant environments. |
Sirbu, Alina; Loreto, Vittorio; Servedio, Vito Domenico Pietro; Tria, Francesca Cohesion, consensus and extreme information in opinion dynamics Journal Article ADVANCES IN COMPLEX SYSTEM, 16 , 2013. Abstract | Links | BibTeX | Tag: loreto, opinion_dynamics, servedio, sirbu, tria @article{b, title = {Cohesion, consensus and extreme information in opinion dynamics}, author = {Alina Sirbu and Vittorio Loreto and Vito Domenico Pietro Servedio and Francesca Tria}, url = {http://www.worldscientific.com/doi/abs/10.1142/S0219525913500355}, year = {2013}, date = {2013-01-01}, journal = {ADVANCES IN COMPLEX SYSTEM}, volume = {16}, publisher = {WORLD SCIENTIFIC PUBL CO PTE LTD}, abstract = {Opinion formation is an important element of social dynamics. It has been widely studied in the last years with tools from physics, mathematics and computer science. Here, a continuous model of opinion dynamics for multiple possible choices is analyzed. Its main features are the inclusion of disagreement and possibility of modulating external information/media effects, both from one and multiple sources. The interest is in identifying the effect of the initial cohesion of the population, the interplay between cohesion and media extremism, and the effect of using multiple external sources of information that can influence the system. Final consensus, especially with the external message, depends highly on these factors, as numerical simulations show. When no external input is present, consensus or segregation is determined by the initial cohesion of the population. Interestingly, when only one external source of information is present, consensus can be obtained, in general, only when this is extremely neutral, i.e., there is not a single opinion strongly promoted, or in the special case of a large initial cohesion and low exposure to the external message. On the contrary, when multiple external sources are allowed, consensus can emerge with one of them even when this is not extremely neutral, i.e., it carries a strong message, for a large range of initial conditions.}, keywords = {loreto, opinion_dynamics, servedio, sirbu, tria}, pubstate = {published}, tppubtype = {article} } Opinion formation is an important element of social dynamics. It has been widely studied in the last years with tools from physics, mathematics and computer science. Here, a continuous model of opinion dynamics for multiple possible choices is analyzed. Its main features are the inclusion of disagreement and possibility of modulating external information/media effects, both from one and multiple sources. The interest is in identifying the effect of the initial cohesion of the population, the interplay between cohesion and media extremism, and the effect of using multiple external sources of information that can influence the system. Final consensus, especially with the external message, depends highly on these factors, as numerical simulations show. When no external input is present, consensus or segregation is determined by the initial cohesion of the population. Interestingly, when only one external source of information is present, consensus can be obtained, in general, only when this is extremely neutral, i.e., there is not a single opinion strongly promoted, or in the special case of a large initial cohesion and low exposure to the external message. On the contrary, when multiple external sources are allowed, consensus can emerge with one of them even when this is not extremely neutral, i.e., it carries a strong message, for a large range of initial conditions. |
Sirbu, Alina; Loreto, Vittorio; Servedio, Vito Domenico Pietro; Tria, Francesca Opinion Dynamics with Disagreement and Modulated Information Journal Article JOURNAL OF STATISTICAL PHYSICS, 151 , pp. 218–237, 2013. Abstract | BibTeX | Tag: loreto, opinion_dynamics, servedio, sirbu, tria @article{b, title = {Opinion Dynamics with Disagreement and Modulated Information}, author = {Alina Sirbu and Vittorio Loreto and Vito Domenico Pietro Servedio and Francesca Tria}, year = {2013}, date = {2013-01-01}, journal = {JOURNAL OF STATISTICAL PHYSICS}, volume = {151}, pages = {218--237}, abstract = {Opinion dynamics concerns social processes through which populations or groups of individuals agree or disagree on specific issues. As such, modelling opinion dynamics represents an important research area that has been progressively acquiring relevance in many different domains. Existing approaches have mostly represented opinions through discrete binary or continuous variables by exploring a whole panoply of cases: e.g. independence, noise, external effects, multiple issues. In most of these cases the crucial ingredient is an attractive dynamics through which similar or similar enough agents get closer. Only rarely the possibility of explicit disagreement has been taken into account (i.e., the possibility for a repulsive interaction among individuals' opinions), and mostly for discrete or 1-dimensional opinions, through the introduction of additional model parameters. Here we introduce a new model of opinion formation, which focuses on the interplay between the possibility of explicit disagreement, modulated in a self-consistent way by the existing opinions' overlaps between the interacting individuals, and the effect of external information on the system. Opinions are modelled as a vector of continuous variables related to multiple possible choices for an issue. Information can be modulated to account for promoting multiple possible choices. Numerical results show that extreme information results in segregation and has a limited effect on the population, while milder messages have better success and a cohesion effect. Additionally, the initial condition plays an important role, with the population forming one or multiple clusters based on the initial average similarity between individuals, with a transition point depending on the number of opinion choices.}, keywords = {loreto, opinion_dynamics, servedio, sirbu, tria}, pubstate = {published}, tppubtype = {article} } Opinion dynamics concerns social processes through which populations or groups of individuals agree or disagree on specific issues. As such, modelling opinion dynamics represents an important research area that has been progressively acquiring relevance in many different domains. Existing approaches have mostly represented opinions through discrete binary or continuous variables by exploring a whole panoply of cases: e.g. independence, noise, external effects, multiple issues. In most of these cases the crucial ingredient is an attractive dynamics through which similar or similar enough agents get closer. Only rarely the possibility of explicit disagreement has been taken into account (i.e., the possibility for a repulsive interaction among individuals' opinions), and mostly for discrete or 1-dimensional opinions, through the introduction of additional model parameters. Here we introduce a new model of opinion formation, which focuses on the interplay between the possibility of explicit disagreement, modulated in a self-consistent way by the existing opinions' overlaps between the interacting individuals, and the effect of external information on the system. Opinions are modelled as a vector of continuous variables related to multiple possible choices for an issue. Information can be modulated to account for promoting multiple possible choices. Numerical results show that extreme information results in segregation and has a limited effect on the population, while milder messages have better success and a cohesion effect. Additionally, the initial condition plays an important role, with the population forming one or multiple clusters based on the initial average similarity between individuals, with a transition point depending on the number of opinion choices. |
2012 |
Gravino, Pietro; Servedio, Vito D P; Barrat, Alain; Loreto, Vittorio Complex structures and semantics in free word association Journal Article ADVANCES IN COMPLEX SYSTEM, 15 , pp. 1250054–1250075, 2012. Abstract | Links | BibTeX | Tag: barrat, complex_networks, gravino, language_dynamics, loreto, semantic_networks, servedio, wordnet, word_association @article{b, title = {Complex structures and semantics in free word association}, author = {Pietro Gravino and Vito D.P. Servedio and Alain Barrat and Vittorio Loreto}, url = {http://www.worldscinet.com/acs/15/1503n04/S0219525912500543.html http://www.scopus.com/inward/record.url?eid=2-s2.0-84861899272&partnerID=65&md5=4d6ecfe66508c0a3cf8bba8dae67c997 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=000304607400014&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=0c7ff228ccbaaa74236f48834a34396a}, year = {2012}, date = {2012-01-01}, journal = {ADVANCES IN COMPLEX SYSTEM}, volume = {15}, pages = {1250054--1250075}, publisher = {WORLD SCIENTIFIC PUBL CO PTE LTD}, abstract = {We investigate the directed and weighted complex network of free word associations in which players write a word in response to another word given as input. We analyze in details two large datasets resulting from two very different experiments: On the one hand the massive multiplayer web-based Word Association Game known as Human Brain Cloud, and on the other hand the South Florida Free Association Norms experiment. In both cases, the networks of associations exhibit quite robust properties like the small world property, a slight assortativity and a strong asymmetry between in-degree and out-degree distributions. A particularly interesting result concerns the existence of a characteristic scale for the word association process, arguably related to specific conceptual contexts for each word. After mapping, the Human Brain Cloud network onto the WordNet semantics network, we point out the basic cognitive mechanisms underlying word associations when they are represented as paths in an underlying semantic network. We derive in particular an expression describing the growth of the HBC graph and we highlight the existence of a characteristic scale for the word association process.}, keywords = {barrat, complex_networks, gravino, language_dynamics, loreto, semantic_networks, servedio, wordnet, word_association}, pubstate = {published}, tppubtype = {article} } We investigate the directed and weighted complex network of free word associations in which players write a word in response to another word given as input. We analyze in details two large datasets resulting from two very different experiments: On the one hand the massive multiplayer web-based Word Association Game known as Human Brain Cloud, and on the other hand the South Florida Free Association Norms experiment. In both cases, the networks of associations exhibit quite robust properties like the small world property, a slight assortativity and a strong asymmetry between in-degree and out-degree distributions. A particularly interesting result concerns the existence of a characteristic scale for the word association process, arguably related to specific conceptual contexts for each word. After mapping, the Human Brain Cloud network onto the WordNet semantics network, we point out the basic cognitive mechanisms underlying word associations when they are represented as paths in an underlying semantic network. We derive in particular an expression describing the growth of the HBC graph and we highlight the existence of a characteristic scale for the word association process. |
2008 |
Cattuto, Ciro; Baldassarri, Andrea; Servedio, Vito D P; Loreto, Vittorio Emergent Community Structure in Social Tagging Systems Journal Article ADVANCES IN COMPLEX SYSTEM, 11 , pp. 597–608, 2008. Links | BibTeX | Tag: baldassarri, cattuto, loreto, servedio, techno_social_systems @article{b, title = {Emergent Community Structure in Social Tagging Systems}, author = {Ciro Cattuto and Andrea Baldassarri and Vito D.P. Servedio and Vittorio Loreto}, url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=000261389600008&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=0c7ff228ccbaaa74236f48834a34396a}, year = {2008}, date = {2008-01-01}, journal = {ADVANCES IN COMPLEX SYSTEM}, volume = {11}, pages = {597--608}, publisher = {WORLD SCIENTIFIC PUBL CO PTE LTD, JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE, SINGAPORE, 912805}, keywords = {baldassarri, cattuto, loreto, servedio, techno_social_systems}, pubstate = {published}, tppubtype = {article} } |
2007 |
Cattuto, Ciro; Schmitz, Christoph; Baldassarri, Andrea; Servedio, Vito D P; Loreto, Vittorio; Hotho, Andreas; Grahl, Martin; Stumme, Gerd Network properties of folksonomies Journal Article AI COMMUNICATIONS, 20 , pp. 245–262, 2007. BibTeX | Tag: baldassarri, cattuto, hotho, loreto, schmitz, servedio, stumme, techno_social_systems @article{b, title = {Network properties of folksonomies}, author = {Ciro Cattuto and Christoph Schmitz and Andrea Baldassarri and Vito D.P. Servedio and Vittorio Loreto and Andreas Hotho and Martin Grahl and Gerd Stumme}, year = {2007}, date = {2007-01-01}, journal = {AI COMMUNICATIONS}, volume = {20}, pages = {245--262}, publisher = {IOS Press:Nieuwe Hemweg 6B, 1013 BG Amsterdam Netherlands:011 31 20 6883355, EMAIL: r.tosendjojo@iospress.nl, INTERNET: http://www.iospress.nl, Fax: 011 31 20 6203419}, keywords = {baldassarri, cattuto, hotho, loreto, schmitz, servedio, stumme, techno_social_systems}, pubstate = {published}, tppubtype = {article} } |
Cattuto, Ciro; Baldassarri, Andrea; Servedio, Vito D P; Loreto, Vittorio Vocabulary growth in collaborative tagging systems Journal Article 2007. BibTeX | Tag: baldassarri, cattuto, loreto, servedio, techno_social_systems @article{b, title = {Vocabulary growth in collaborative tagging systems}, author = {Ciro Cattuto and Andrea Baldassarri and Vito D.P. Servedio and Vittorio Loreto}, year = {2007}, date = {2007-01-01}, publisher = {arXiv.org > cs > arXiv:0704.3316}, keywords = {baldassarri, cattuto, loreto, servedio, techno_social_systems}, pubstate = {published}, tppubtype = {article} } |
2006 |
Cattuto, Ciro; Loreto, Vittorio; Servedio, Vito D P A Yule-Simon process with long-term memory Journal Article EUROPHYSICS LETTERS, 76 , pp. 208–214, 2006. Links | BibTeX | Tag: cattuto, language_dynamics, loreto, servedio, techno_social_systems @article{b, title = {A Yule-Simon process with long-term memory}, author = {Ciro Cattuto and Vittorio Loreto and Vito D.P. Servedio}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-33750355454&partnerID=65&md5=97945c5a7352e4354fd77989abe1b901 http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=000241076600006&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=0c7ff228ccbaaa74236f48834a34396a}, year = {2006}, date = {2006-01-01}, journal = {EUROPHYSICS LETTERS}, volume = {76}, pages = {208--214}, publisher = {EDP Sciences:17 Ave Du Hoggar, BP112, 91944 Les Ulis Cedex A France:011 33 1 69187575, EMAIL: subscribers@edpsciences.com, INTERNET: http://www.edpsciences.com, Fax: 011 33 1 69860678}, keywords = {cattuto, language_dynamics, loreto, servedio, techno_social_systems}, pubstate = {published}, tppubtype = {article} } |
Other subjects
