TY - JOUR T1 - Ecosystem antifragility: beyond integrity and resilience JF - PeerJ Y1 - 2020 A1 - Equihua, Miguel A1 - Espinosa Aldama, Mariana A1 - Gershenson, Carlos A1 - López-Corona, Oliver A1 - Munguía, Mariana A1 - Pérez-Maqueo, Octavio A1 - Ramírez-Carrillo, Elvia KW - Antifragility KW - Complexity KW - Ecosystem integrity KW - Resilience AB - We review the concept of ecosystem resilience in its relation to ecosystem integrity from an information theory approach. We summarize the literature on the subject identifying three main narratives: ecosystem properties that enable them to be more resilient; ecosystem response to perturbations; and complexity. We also include original ideas with theoretical and quantitative developments with application examples. The main contribution is a new way to rethink resilience, that is mathematically formal and easy to evaluate heuristically in real-world applications: ecosystem antifragility. An ecosystem is antifragile if it benefits from environmental variability. Antifragility therefore goes beyond robustness or resilience because while resilient/robust systems are merely perturbation-resistant, antifragile structures not only withstand stress but also benefit from it. VL - 8 UR - https://doi.org/10.7717/peerj.8533 ER - TY - JOUR T1 - Measuring the complexity of adaptive peer-to-peer systems JF - Peer-to-Peer Networking and Applications Y1 - 2015 A1 - Amoretti, Michele A1 - Gershenson, Carlos KW - Adaptive peer-to-peer system KW - Complexity KW - Evolution KW - Information theory AB - To improve the efficiency of peer-to-peer (P2P) systems while adapting to changing environmental conditions, static peer-to-peer protocols can be replaced by adaptive plans. The resulting systems are inherently complex, which makes their development and characterization a challenge for traditional methods. Here we propose the design and analysis of adaptive P2P systems using measures of complexity, emergence, self-organization, and homeostasis based on information theory. These measures allow the evaluation of adaptive P2P systems and thus can be used to guide their design. We evaluate the proposal with a P2P computing system provided with adaptation mechanisms. We show the evolution of the system with static and also changing workload, using different fitness functions. When the adaptive plan forces the system to converge to a predefined performance level, the nodes may result in highly unstable configurations, which correspond to a high variance in time of the measured complexity. Conversely, if the adaptive plan is less ``aggressive'', the system may be more stable, but the optimal performance may not be achieved. SN - 1936-6442 UR - http://dx.doi.org/10.1007/s12083-015-0385-4 ER - TY - JOUR T1 - When slower is faster JF - Complexity Y1 - 2015 A1 - Gershenson, Carlos A1 - Helbing, Dirk KW - cascading effects KW - collective motion KW - Evolution KW - phase transitions AB - The slower is faster (SIF) effect occurs when a system performs worse as its components try to do better. Thus, a moderate individual efficiency actually leads to a better systemic performance. The SIF effect takes place in a variety of phenomena. We review studies and examples of the SIF effect in pedestrian dynamics, vehicle traffic, traffic light control, logistics, public transport, social dynamics, ecological systems, and adaptation. Drawing on these examples, we generalize common features of the SIF effect and suggest possible future lines of research. {\copyright} 2015 Wiley Periodicals, Inc. Complexity 21: 9–15, 2015 VL - 21 UR - http://arxiv.org/abs/1506.06796 ER - TY - JOUR T1 - Living in Living Cities JF - Artificial Life Y1 - 2013 A1 - Carlos Gershenson KW - cities KW - Self-organization KW - traffic KW - transport AB -

This paper presents and overview of current and potential applications of living technology to urban problems. Living technology can be described as technology that exhibits the core features of living systems. These features can be useful to solve dynamic problems. In particular, urban problems concerning mobility, logistics, telecommunications, governance, safety, sustainability, and society and culture are presented, while solutions involving living technology are reviewed. A methodology for developing living technology is mentioned, while self-organizing traffic lights are used as a case study of the benefits of urban living technology. Finally, the usefulness of describing cities as living systems is discussed.

VL - In Press UR - http://arxiv.org/abs/1111.3659 ER - TY - BOOK T1 - Design and Control of Self-organizing Systems Y1 - 2007 A1 - Carlos Gershenson KW - Complexity Theory KW - Physics KW - Self-organization AB - Complex systems are usually difficult to design and control. There are several particular methods for coping with complexity, but there is no general approach to build complex systems. In this book I pro- pose a methodology to aid engineers in the design and control of com- plex systems. This is based on the description of systems as self- organizing. Starting from the agent metaphor, the methodology pro- poses a conceptual framework and a series of steps to follow to find proper mechanisms that will promote elements to find solutions by ac- tively interacting among themselves. The main premise of the method- ology claims that reducing the "friction" of interactions between el- ements of a system will result in a higher "satisfaction" of the system, i.e. better performance. A general introduction to complex thinking is given, since designing self-organizing systems requires a non-classical thought, while prac- tical notions of complexity and self-organization are put forward. To illustrate the methodology, I present three case studies. Self-organizing traffic light controllers are proposed and studied with multi-agent simulations, outperforming traditional methods. Methods for im- proving communication within self-organizing bureaucracies are ad- vanced, introducing a simple computational model to illustrate the benefits of self-organization. In the last case study, requirements for self-organizing artifacts in an ambient intelligence scenario are dis- cussed. Philosophical implications of the conceptual framework are also put forward. PB - CopIt Arxives CY - Mexico SN - 978-0-9831172-3-0 UR - http://tinyurl.com/DCSOS2007 N1 - http://tinyurl.com/DCSOS2007 ER -