Complexity & Systems
9.0K views | +5 today

# Complexity & Systems

Complex systems present problems both in mathematical modelling and philosophical foundations. The study of complex systems represents a new approach to science that investigates how relationships between parts give rise to the collective behaviors of a system and how the system interacts and forms relationships with its environment. The equations from which models of complex systems are developed generally derive from statistical physics, information theory and non-linear dynamics, and represent organized but unpredictable behaviors of natural systems that are considered fundamentally complex.  wikipedia (en)
 Scooped by Bernard Ryefield

## Evolution’s Contrarian Capacity for Creativity - Facts So Romantic - Nautilus

One can imagine life evolving again and again, crashing on the rocks of time and circumstance, until finally it hit upon just the right mutation rate—one that eons later would produce organisms and species and ecosystems.

No comment yet.
 Rescooped by Bernard Ryefield from Creativity - Problem Solving

## Studying Collective Human Decision Making and Creativity with Evolutionary Computation

We report a summary of our interdisciplinary research project "Evolutionary Perspective on Collective Decision Making" that was conducted through close collaboration between computational, organizational and social scientists at Binghamton University. We redefined collective human decision making and creativity as evolution of ecologies of ideas, where populations of ideas evolve via continual applications of evolutionary operators such as reproduction, recombination, mutation, selection, and migration of ideas, each conducted by participating humans. Based on this evolutionary perspective, we generated hypotheses about collective human decision making using agent-based computer simulations. The hypotheses were then tested through several experiments with real human subjects. Throughout this project, we utilized evolutionary computation (EC) in non-traditional ways---(1) as a theoretical framework for reinterpreting the dynamics of idea generation and selection, (2) as a computational simulation model of collective human decision making processes, and (3) as a research tool for collecting high-resolution experimental data of actual collaborative design and decision making from human subjects. We believe our work demonstrates untapped potential of EC for interdisciplinary research involving human and social dynamics.

No comment yet.
 Rescooped by Bernard Ryefield from Complex Systems and X-Events

## Are Big, Rich Cities Greener Than Poor Ones?

When it comes to cities, being big and rich is better for the planet than being big and poor, according to a new study of carbon dioxide emissions from cities around the world. But is this correct?

Via Claudia Mihai, Roger D. Jones, PhD
No comment yet.
 Scooped by Bernard Ryefield

## Global Civil Unrest: Contagion, Self-Organization, and Prediction

Civil unrest is a powerful form of collective human dynamics, which has led to major transitions of societies in modern history. The study of collective human dynamics, including collective aggression, has been the focus of much discussion in the context of modeling and identification of universal patterns of behavior. In contrast, the possibility that civil unrest activities, across countries and over long time periods, are governed by universal mechanisms has not been explored. Here, records of civil unrest of 170 countries during the period 1919–2008 are analyzed. It is demonstrated that the distributions of the number of unrest events per year are robustly reproduced by a nonlinear, spatially extended dynamical model, which reflects the spread of civil disorder between geographic regions connected through social and communication networks. The results also expose the similarity between global social instability and the dynamics of natural hazards and epidemics.

No comment yet.
 Rescooped by Bernard Ryefield from Non-Equilibrium Social Science

## The Science of Inequality

In 2011, the wrath of the 99% kindled Occupy movements around the world. The protests petered out, but in their wake an international conversation about inequality has arisen, with tens of thousands of speeches, articles, and blogs engaging everyone from President Barack Obama on down. Ideology and emotion drive much of the debate. But increasingly, the discussion is sustained by a tide of new data on the gulf between rich and poor.

This special issue uses these fresh waves of data to explore the origins, impact, and future of inequality around the world. Archaeological and ethnographic data are revealing how inequality got its start in our ancestors (see pp. 822 and 824). New surveys of emerging economies offer more reliable estimates of people's incomes and how they change as countries develop (see p. 832). And in the past decade in developed capitalist nations, intensive effort and interdisciplinary collaborations have produced large data sets, including the compilation of a century of income data and two centuries of wealth data into the World Top Incomes Database (WTID) (see p. 826 and Piketty and Saez, p. 838).

Science 23 May 2014:
Vol. 344 no. 6186 pp. 818-821
DOI: 10.1126/science.344.6186.818

Via NESS
No comment yet.
 Scooped by Bernard Ryefield

## Nigel Goldenfeld: We Need a Theory of Life

I was intrigued when Carl Woese told me his collaboration with University of Illinois physicist Nigel Goldenfeld was the most productive one of his entire career, and was pleased to finally run into Goldenfeld last September at lunch in the courtyard...
No comment yet.
 Scooped by Bernard Ryefield

## ▶ Large-Scale Structure in Networks - YouTube

Mark Newman May 2, 2014 Annual Science Board Symposium and Meeting Complexity: Theory and Practice
Eli Levine's curator insight,

To know the structure is to know a HUMONGOUS part of the function and, thus, the ability to predict.  It seems to me to be a large fractal pattern of clusters, nodes and connections (but, that is just in my relatively uneducated eye).

Never forget, though, that there are important qualitative aspects to networks (think of defacto qualities of the nodes, groups of nodes and the connections amongst them).  Very important for social and/or ecological/causal relation networks (essentially, a network that outlines and maps accurately the function of a system and all of the flows of information and material resources).

Really cool stuff here.

 Scooped by Bernard Ryefield

## Dynamics of Complex Systems - Y. Bar-Yam

Textbook for seminar/course on complex systems.
View full text in PDF format

The study of complex systems in a unified framework has become recognized in recent years as a new scientific discipline, the ultimate of interdisciplinary fields. Breaking down the barriers between physics, chemistry and biology and the so-called soft sciences of psychology, sociology, economics, and anthropology, this text explores the universal physical and mathematical principles that govern the emergence of complex systems from simple components.

No comment yet.
 Scooped by Bernard Ryefield

## Agent Based Modeling of Complex Adaptive Systems - advanced : Course Home

Building on Complex Adaptive Systems theory and basic Agent Based Modeling knowledge presented in SPM4530, the Advanced course will focus on the model development process. The students are expected to conceptualize, develop and verify a model during the course, individually or in a group. The modeling tasks will be, as much as possible, based on real life research problems, formulated by various research groups from within and outside the faculty.

Study Goals
The main goal of the course is to learn how to form a modeling question, perform a system decomposition, conceptualize and formalize the system elements, implement and verify the simulation and validate an Agent Based Model of a socio-technical system.

No comment yet.
 Scooped by Bernard Ryefield

## Dynamics of Complex Systems | NECSI | Libros y ...

Complejidady Economía's insight: Full Online Text (Dynamics of Complex Systems | NECSI | @scoopit http://t.co/sVePaP2sG2)
No comment yet.
 Scooped by Bernard Ryefield

## Insights from the Wikipedia Contest (IEEE Contest for Data Mining 2011)

The Wikimedia Foundation has recently observed that newly joining editors on Wikipedia are increasingly failing to integrate into the Wikipedia editors' community, i.e. the community is becoming increasingly harder to penetrate. To sustain healthy growth of the community, the Wikimedia Foundation aims to quantitatively understand the factors that determine the editing behavior, and explain why most new editors become inactive soon after joining. As a step towards this broader goal, the Wikimedia foundation sponsored the ICDM (IEEE International Conference for Data Mining) contest for the year 2011.
The objective for the participants was to develop models to predict the number of edits that an editor will make in future five months based on the editing history of the editor. Here we describe the approach we followed for developing predictive models towards this goal, the results that we obtained and the modeling insights that we gained from this exercise. In addition, towards the broader goal of Wikimedia Foundation, we also summarize the factors that emerged during our model building exercise as powerful predictors of future editing activity.

No comment yet.
 Scooped by Bernard Ryefield

## Complex contagion process in spreading of online innovation

Diffusion of innovation can be interpreted as a social spreading phenomena governed by the impact of media and social interactions. Although these mechanisms have been identified by quantitative theories, their role and relative importance are not entirely understood, since empirical verification has so far been hindered by the lack of appropriate data. Here we analyse a dataset recording the spreading dynamics of the world's largest Voice over Internet Protocol service to empirically support the assumptions behind models of social contagion. We show that the probability of spontaneous service adoption is constant, the probability of adoption via social influence is linearly proportional to the fraction of adopting neighbours, and the probability of service termination is time-invariant and independent of the behaviour of peers. By implementing the detected diffusion mechanisms into a dynamical agent-based model, we are able to emulate the adoption dynamics of the service in several countries worldwide. This approach enables us to make medium-term predictions of service adoption and disclose dependencies between the dynamics of innovation spreading and the socioeconomic development of a country.

No comment yet.
 Scooped by Bernard Ryefield

## Saving Human Lives: What Complexity Science and Information Systems can Contribute

We discuss models and data of crowd disasters, crime, terrorism, war and disease spreading to show that conventional recipes, such as deterrence strategies, are often not effective and sufficient to contain them. Many common approaches do not provide a good picture of the actual system behavior, because they neglect feedback loops, instabilities and cascade effects. The complex and often counter-intuitive behavior of social systems and their macro-level collective dynamics can be better understood by means of complexity science. We highlight that a suitable system design and management can help to stop undesirable cascade effects and to enable favorable kinds of self-organization in the system. In such a way, complexity science can help to save human lives.

No comment yet.
 Scooped by Bernard Ryefield

## Large-scale Fluctuations of Lyapunov Exponents in Diffusive Systems

We present a general formalism for computing Lyapunov exponents and their fluctuations in spatially extended systems described by diffusive fluctuating hydrodynamics, thus extending the concepts of dynamical system theory to a broad range of non-equilibrium systems. Our analytical results compare favorably with simulations of a lattice model of heat conduction. We further show how the computation of Lyapunov exponents for the Symmetric Simple Exclusion Process relates to damage spreading and to a two-species pair annihilation process, for which our formalism yields new finite size results.

No comment yet.
 Scooped by Bernard Ryefield

## Combining segregation and integration: Schelling model dynamics for heterogeneous population

The Schelling model is a simple agent based model that demonstrates how individuals' relocation decisions generate residential segregation in cities. Agents belong to one of two groups and occupy cells of rectangular space. Agents react to the fraction of agents of their own group within the neighborhood around their cell. Agents stay put when this fraction is above a given tolerance threshold but seek a new location if the fraction is below the threshold. The model is well known for its tipping point behavior: an initial random (integrated) pattern remains integrated when the tolerance threshold is below 1/3 but becomes segregated when the tolerance threshold is above 1/3.
In this paper, we demonstrate that the variety of the Schelling model steady patterns is richer than the segregation-integration dichotomy and contains patterns that consist of segregated patches for each of the two groups alongside patches where both groups are spatially integrated. We obtain such patterns by considering a general version of the model in which the mechanisms of agents' interactions remain the same but the tolerance threshold varies between agents of both groups.
We show that the model produces patterns of mixed integration and segregation when the tolerance threshold of most agents is either below the tipping point or above 2/3. In these cases, the mixed patterns are relatively insensitive to the model's parameters.

No comment yet.
 Rescooped by Bernard Ryefield from Global Brain

## Game Theory Makes New Predictions for Evolution | Simons Foundation

An insight borrowed from computer science suggests that evolution values both fitness and diversity.

Via Spaceweaver
No comment yet.
 Rescooped by Bernard Ryefield from Papers

## The direction of evolution: The rise of cooperative organization

Two great trends are evident in the evolution of life on Earth: towards increasing diversification and towards increasing integration. Diversification has spread living processes across the planet, progressively increasing the range of environments and free energy sources exploited by life. Integration has proceeded through a stepwise process in which living entities at one level are integrated into cooperative groups that become larger-scale entities at the next level, and so on, producing cooperative organizations of increasing scale (for example, cooperative groups of simple cells gave rise to the more complex eukaryote cells, groups of these gave rise to multi-cellular organisms, and cooperative groups of these organisms produced animal societies). The trend towards increasing integration has continued during human evolution with the progressive increase in the scale of human groups and societies. The trends towards increasing diversification and integration are both driven by selection. An understanding of the trajectory and causal drivers of the trends suggests that they are likely to culminate in the emergence of a global entity. This entity would emerge from the integration of the living processes, matter, energy and technology of the planet into a global cooperative organization. Such an integration of the results of previous diversifications would enable the global entity to exploit the widest possible range of resources across the varied circumstances of the planet. This paper demonstrates that it's case for directionality meets the tests and criticisms that have proven fatal to previous claims for directionality in evolution.

The direction of evolution: The rise of cooperative organization
John E. Stewart

Biosystems
Available online 1 June 2014

http://dx.doi.org/10.1016/j.biosystems.2014.05.006

Via Complexity Digest
Eli Levine's curator insight,

Cooperation is the best way to improve, sustain, maintain, and repair.  Competition is what drives everyone and everything towards something different, be it competition for resources or competition against the elements around us.

I don't get what the point of competition amongst the species is for.  Part of cooperation, after all, is knowing what works, learning about what could work better or doesn't work, and then letting the negative or sub-optimal slip back beneath the waves of ignorance, such that the new ways can rise to prominence.

Change is the only constant in this universe of universes.

Yet cooperation, I think, yields the higher and stronger of the universal structures that are out there, even if it means that there are still losers and winners.  The only difference is the level of consent and consensus that's reached within the social, ecological, economical, and/or political landscape.  One way works towards what is best.  The other way simply yields what is best at competing, which is not the same as being the actual best solution to a given problem or condition.

Luciano Lampi's curator insight,

is this the end of stove pipes?

Ra's curator insight,

Have I been reading too much science fiction?

 Scooped by Bernard Ryefield

## NSF Research Helps UNESCO Preserve Subaks in Bali

Immersed in the world of Balinese water temples and cooperative farms, Anthropologist J. Stephen Lansing’s NSF funded research helped win UNESCO World Heritage Site status for Bali’s subaks.
No comment yet.
 Scooped by Bernard Ryefield

## Designing Complex Dynamics in Cellular Automata with Memory

Since their inception at Macy conferences in later 1940s complex systems remain the most controversial topic of inter-disciplinary sciences. The term complex system' is the most vague and liberally used scientific term. Using elementary cellular automata (ECA), and exploiting the CA classification, we demonstrate elusiveness of complexity' by shifting space-time dynamics of the automata from simple to complex by enriching cells with {\it memory}. This way, we can transform any ECA class to another ECA class --- without changing skeleton of cell-state transition function --- and vice versa by just selecting a right kind of memory. A systematic analysis display that memory helps `discover' hidden information and behaviour on trivial --- uniform, periodic, and non-trivial --- chaotic, complex --- dynamical systems.

No comment yet.
 Suggested by Samir

## ECCS 2014 Satellite

Workshop on Robustness, Adaptability and Critical Transitions in Living Systems. Submit your Abstract at http://seis.bristol.ac.uk/~fs13378/eccs_2014_livingsys.html

No comment yet.
 Scooped by Bernard Ryefield

## Networks as a Privileged Way to Develop Mesoscopic Level Approaches in Systems Biology

The methodologies advocated in computational biology are in many cases proper system-level approaches. These methodologies are variously connected to the notion of “mesosystem” and thus on the focus on relational structures that are at the basis of biological regulation. Here, I describe how the formalization of biological systems by means of graph theory constitutes an extremely fruitful approach to biology. I suggest the epistemological relevance of the notion of graph resides in its multilevel character allowing for a natural “middle-out” causation making largely obsolete the traditional opposition between “top-down” and “bottom-up” styles of reasoning, so fulfilling the foundation dream of systems science of a direct link between systems analysis and the underlying physical reality.

No comment yet.
 Scooped by Bernard Ryefield

## COLLECTIVE ADAPTATIVE SYSTEMS SYNTHESIS WITH NON-ZERO-SUM GAMES

The objective of CASSTING is to develop a novel approach for analysing and designing collective adaptive systems in their totality, by setting up a game theoretic framework. Here components are viewed as players, their behaviour is captured by strategies, system runs are plays, and specifications are winning conditions. We will develop formalisms for modelling collective adaptive systems as games, and algorithms for synthesising optimal strategies (and components).

No comment yet.
 Scooped by Bernard Ryefield

## 3rd International Conference on Complex Dynamical Systems and Their Applications: New Mathematical Concepts and Applications | The European Mathematical Society

3rd International Conference on Complex Dynamical Systems and Their Applications: New Mathematical Concepts and... http://t.co/Wd83nLP9Ik
No comment yet.
 Scooped by Bernard Ryefield

## The influence of persuasion in opinion formation and polarization

We present a model that explores the influence of persuasion in a population of agents with positive and negative opinion orientations. The opinion of each agent is represented by an integer number k that expresses its level of agreement on a given issue, from totally against k=-M to totally in favor k=M. Same-orientation agents persuade each other with probability p, becoming more extreme, while opposite-orientation agents become more moderate as they reach a compromise with probability q. The population initially evolves to (a) a polarized state for r=p/q>1, where opinions' distribution is peaked at the extreme values k=±M, or (b) a centralized state for r<1, with most opinions around k=±1. When r»1, polarization lasts for a time that diverges as rMlnN, where N is the population's size. Finally, an extremist consensus (k=M or -M) is reached in a time that scales as r-1 for r«1.

No comment yet.
 Rescooped by Bernard Ryefield from Talks

## Nonlinear Dynamics and Chaos - Steven Strogatz, Cornell University - YouTube

This course of 25 lectures, filmed at Cornell University in Spring 2014, is intended for newcomers to nonlinear dynamics and chaos. It closely follows Prof. Strogatz's book, "Nonlinear Dynamics and Chaos: With Applications to Physics, Biology, Chemistry, and Engineering." The mathematical treatment is friendly and informal, but still careful. Analytical methods, concrete examples, and geometric intuition are stressed. The theory is developed systematically, starting with first-order differential equations and their bifurcations, followed by phase plane analysis, limit cycles and their bifurcations, and culminating with the Lorenz equations, chaos, iterated maps, period doubling, renormalization, fractals, and strange attractors. A unique feature of the course is its emphasis on applications. These include airplane wing vibrations, biological rhythms, insect outbreaks, chemical oscillators, chaotic waterwheels, and even a technique for using chaos to send secret messages. In each case, the scientific background is explained at an elementary level and closely integrated with the mathematical theory. The theoretical work is enlivened by frequent use of computer graphics, simulations, and videotaped demonstrations of nonlinear phenomena. The essential prerequisite is single-variable calculus, including curve sketching, Taylor series, and separable differential equations. In a few places, multivariable calculus (partial derivatives, Jacobian matrix, divergence theorem) and linear algebra (eigenvalues and eigenvectors) are used. Fourier analysis is not assumed, and is developed where needed. Introductory physics is used throughout. Other scientific prerequisites would depend on the applications considered, but in all cases, a first course should be adequate preparation

Nonlinear Dynamics and Chaos - Steven Strogatz, Cornell University