Complexity - Comp...
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# Complexity - Complex Systems Theory

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)
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## You clap, so I clap: Peer pressure drives applause

If you have just seen a play that you privately think is drivel, will you keep silent when everyone around you demands an encore?
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## The nature of collective intelligence

Digital data stem from our own personal and social cognitive processes and thus express them in one way or another. But we still don’t have any scientific tools to make sense of the data flows produced by online creative conversations at the scale of the digital medium as a whole.

Presentation by Pierre Levy

Via Viktor Markowski, Complexity Digest
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Pierre Lévy invented IEML; think semantic web

Viktor Markowski's curator insight,

45 minute video presentation supported by slides on the nature of collective intelligence and the philosophical and technical construct behind the next level of the internet as a global mind.

Luciano Lampi's curator insight,

Pierre Levy, c´est toujours très intéressant!

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## Complex systems: counterintuitive behavior and disproportionate causal effets

Presentation on the counterintuitive behavior and disproportionate causal effects of complex system. Illustration using the the example of restaurant dynamics determined…
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## Is there an invisible tug-of-war behind bad hearts and power outages?

Systems such as a beating heart or a power grid that depend on the synchronized movement of their parts could fall prey to an invisible and chaotic tug-of-war known as a "chimera." Sharing its name with the fire-breathing, zoologically patchy...
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## New England Complex Systems Institute

The New England Complex Systems Institute (NECSI) is an independent academic research and educational institution with students, postdoctoral fellows and faculty. In addition to the in-house research team, NECSI has co-faculty, students and affiliates from MIT, Harvard, Brandeis and other universities nationally and internationally.

NECSI has been instrumental in the development of complex systems science and its applications. We study how interactions within a system lead to its behavioral patterns, and how the system interacts with its environment. Our new tools overcome the limitations of classical approximations for the scientific study of complex systems, such as social organizations, biological organisms and ecological communities. NECSI's unified mathematically-based approach transcends the boundaries of physical, biological and social sciences, as well as engineering, management, and medicine.

NECSI research advances fundamental science and its applications to real world problems, including social policy matters. NECSI researchers study networks, agent-based modeling, multiscale analysis and complexity, chaos and predictability, evolution, ecology, biodiversity, altruism, systems biology, cellular response, health care, systems engineering, negotiation, military conflict, ethnic violence, and international development.

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Among the NECSI faculty and affiliates are Terrence Deacon, Thomas Schelling and Uri Wilensky

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## Keynote - Edgar Morin - Complex thinking for a complex world

Our world is at crisis. Global challenges abound. However, they have a "dark" and a "bright" side. The dark side is the imminent danger of the breakdown of interdependent societies with the perspective of extermination of civilised human life. The bright side marks a possible entrance to a new stage of evolution of humanity, to the self-organisation of a humane world society. Cybernetics, systems research, the sciences of complexity -- all of them have the potential to endow the subjects of history with guidance and a means for mastering the current transformation.

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## Complexity Rising: From Human Beings to Human C...

Since time immemorial humans have complained that life is becoming more complex, but it is only now that we have a hope to analyze formally and verify this lament. This article analyzes the human social environment using the "complexity profile," a mathematical tool for characterizing the collective behavior of a system. The analysis is used to justify the qualitative observation that complexity of existence has increased and is increasing. The increase in complexity is directly related to sweeping changes in the structure and dynamics of human civilization—the increasing interdependence of the global economic and social system and the instabilities of dictatorships, communism and corporate hierarchies. Our complex social environment is consistent with identifying global human civilization as an organism capable of complex behavior that protects its components (us) and which should be capable of responding effectively to complex environmental demands.

Via David G Wilson
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## Mathematical Perspective - A 250-year Argument : Belief, Bahavior, and the Bootstrap

The term "controversial theorem" sounds like an oxymoron, but Bayes' theorem has played this part for two-and-a-half centuries. Twice it has soared to scientific celebrity, twice it has crashed, and it is currently enjoying another boom. The theorem itself is a landmark of logical reasoning and the first serious triumph of statistical inference, yet is still treated with suspicion by most statisticians. There are reasons to believe in the staying power of its current popularity, but also some signs of trouble ahead.

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## Geoffrey West on COMPLEXITY

http://fqxi.org Geoffrey West at the FQXi SETTING TIME ARIGHT conference, an interdisciplinary meeting investigating the nature of time.
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Geoffrey Brian West (born 1940 in Taunton, Somerset) is a British theoretical physicist, former president and distinguished professor of the Santa Fe Institute. He is one of the leading scientists working on a scientific model of cities. Among other things his work states that with the doubling of a city's size, services per capita will generally increase by 15%.

http://en.wikipedia.org/wiki/Geoffrey_West

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## Complexity and Transdisciplinarity by Geoffrey West (Part 2 of 13)

The conference More is Different is about complexity. "The 21st century," physicist Stephen Hawking has said, "will be the century of complexity." Likewise, ...

Via Keith Hamon
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http://en.wikipedia.org/wiki/Geoffrey_West

Geoffrey Brian West (born 1940 in Taunton, Somerset) is a British theoretical physicist, former president and distinguished professor of the Santa Fe Institute. He is one of the leading scientists working on a scientific model of cities. Among other things his work states that with the doubling of a city's size, services per capita will generally increase by 15%

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## Temporal fractals in seabird foraging behaviour: diving through the scales of time

Animal behaviour exhibits fractal structure in space and time. Fractal properties in animal space-use have been explored extensively under the Lévy flight foraging hypothesis, but studies of behaviour change itself through time are rarer, have typically used shorter sequences generated in the laboratory, and generally lack critical assessment of their results. We thus performed an in-depth analysis of fractal time in binary dive sequences collected via bio-logging from free-ranging little penguins (Eudyptula minor) across full-day foraging trips (216 data points; 4 orders of temporal magnitude). Results from 4 fractal methods show that dive sequences are long-range dependent and persistent across ca. 2 orders of magnitude. This fractal structure correlated with trip length and time spent underwater, but individual traits had little effect. Fractal time is a fundamental characteristic of penguin foraging behaviour, and its investigation is thus a promising avenue for research on interactions between animals and their environments.

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## Portal:Systems science - Wikipedia, the free encyclopedia

Systems are sets of entities, physical or abstract, comprising a whole where each component interacts with or is related to at least one other component and they all serve a common objective. The scientific research field which is engaged in the interdisciplinary study of universal system-based properties of the world is general system theory, systems science and recently systemics. This field investigates the abstract properties of matter and mind, and their organization, searching for concepts and principles which are independent of the specific domain, substance, and type of system, and of the spatial and/or temporal scales of its existence.

Systems science can be viewed as ... "a metalanguage of concepts and models for interdisciplinary use, still now evolving and far from being stabilized. This is the result of a slow process of accretion through inclusion and interconnection of many notions, which came and are still coming from very different disciplines. The process started more than a century ago, but has gathered momentum since 1948 through the pioneering work of Norbert Wiener, John von Neumann, Ludwig von Bertalanffy, Heinz von Foerster and W. Ross Ashby, among many others" (Charles François, 1999).

The Manila Metro Rail Transit System is part of the metropolitan rail system in the Metro Manila area of the Philippines, the Strong Republic Transit System. Although it has characteristics of light rail, such as the type of rolling stock used, it is more akin to a rapid transit system. It is not related to the Manila Light Rail Transit System, a separate but linked system.

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visualcomplexity.com

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VisualComplexity.com is a unified resource space for anyone interested in the visualization of complex networks. The project's main goal is to leverage a critical understanding of different visualization methods, across a series of disciplines, as diverse as Biology, Social Networks or the World Wide Web.

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## Characteristic exponents of complex networks

We propose a method to characterize and classify complex networks based on the time series generated by random walks and different node properties. The analysis of the fluctuations of the time series reveals the presence of long-range correlations, and allows to define, for each network, a set of characteristic exponents that capture its essential structural properties. By considering a large data set of real-world networks, we show that the characteristic exponents can be used to classify complex networks according to their function, and are able to discriminate social from biological and technological systems.
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## James B. Glattfelder: Who controls the world?

James Glattfelder studies complexity: how an interconnected system -- say, a swarm of birds -- is more than the sum of its parts. And complexity theory, it t...
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the economic world that is

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## The origin of allometric scaling laws in biology from genomes to ecosystems: towards a quantitative unifying theory of biological structure and organization

Geoffrey B. West, James H. Brown

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allometry, quarter-power scaling, laws of life, circulatory system, ontogenetic growth

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## Didier Sornette: How we can predict the next financial crisis

The 2007-2008 financial crisis, you might think, was an unpredictable one-time crash. But Didier Sornette and his Financial Crisis Observatory have plotted a set of early warning signs for unstable, growing systems, tracking the moment when any bubble is about to pop. (And he's seeing it happen again, right now.)

Via Complexity Digest
Bernard Ryefield's insight:

Didier Sornette theory of Dragon-Kings vs Black Swans is supported by a number of concepts from complexity science and certainly needs close scrutinity.

The Illusion of the Perpetual Money Machine

D. Sornette, P. Cauwels

http://arxiv.org/abs/1212.2833

Dragon Kings, Black Swans and the Prediction of Crises

Didier Sornette

http://arxiv.org/abs/0907.4290

Predictability and suppression of extreme events in complex systems

Hugo L. D. de Souza Cavalcante, Marcos Oria, Didier Sornette, Edward Ott, Daniel J. Gauthier

http://arxiv.org/abs/1301.0244

Luciano Lampi's curator insight,

si non é vero...é ben trovato!

ComplexInsight's curator insight,

Didier Sornette and team's work .- highlights role of how system feedback can drive a variety of systems through phase transition resulting in dramatic structural and behavioural change in system behaviour.  While many of the underpinning ideas presented have been discussed extensively in the fields of chaos and complex systems - his teams methods of  analysis and publication combined with the variety of systems he and his team study will hopefully help gain a wider acceptance of using these methods to understand, model and steer systems behaviour. A video well worth watching.

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## Collective behavior and evolutionary games - An introduction

This is an introduction to the special issue titled "Collective behavior and evolutionary games" that is in the making at Chaos, Solitons & Fractals. The term collective behavior covers many different phenomena in nature and society. From bird flocks and fish swarms to social movements and herding effects, it is the lack of a central planner that makes the spontaneous emergence of sometimes beautifully ordered and seemingly meticulously designed behavior all the more sensational and intriguing. The goal of the special issue is to attract submissions that identify unifying principles that describe the essential aspects of collective behavior, and which thus allow for a better interpretation and foster the understanding of the complexity arising in such systems. As the title of the special issue suggests, the later may come from the realm of evolutionary games, but this is certainly not a necessity, neither for this special issue, and certainly not in general. Interdisciplinary work on all aspects of collective behavior, regardless of background and motivation, and including synchronization and human cognition, is very welcome.

Collective behavior and evolutionary games - An introduction

Matjaz Perc, Paolo Grigolini

http://arxiv.org/abs/1306.2296

Via Complexity Digest
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to be followed...

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## 22. Emergence and Complexity

Professor Robert Sapolsky gives a lecture on emergence and complexity. He details how a small difference at one place in nature can have a huge effect on a system as time goes on. He calls this idea fractal magnification and applies it to many different systems that exist throughout nature.

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## Competition-induced criticality in a model of meme popularity

Heavy-tailed distributions of meme popularity occur naturally in a model of meme diffusion on social networks. Competition between multiple memes for the limited resource of user attention is identified as the mechanism that poises the system at criticality. The popularity growth of each meme is described by a critical branching process, and asymptotic analysis predicts power-law distributions of popularity with very heavy tails (exponent $\alpha<2$, unlike preferential-attachment models), similar to those seen in empirical data.

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## Pendulum swings back on 350-year-old mathematical mystery

(Phys.org) —A 350-year-old mathematical mystery could lead toward a better understanding of medical conditions like epilepsy or even the behavior of predator-prey systems in the wild, University of Pittsburgh researchers report.The mystery dates back to 1665, when Dutch mathematician, astronomer, and physicist Christiaan Huygens, inventor of the pendulum clock, first observed that two pendulum clocks mounted together could swing in opposite directions. The cause was tiny vibrations in the beam caused by both clocks, affecting their motions.

The effect, now referred to by scientists as "indirect coupling," was not mathematically analyzed until nearly 350 years later, and deriving a formula that explains it remains a challenge to mathematicians still. Now, Pitt professors apply this principle to measure the interaction of "units"—such as neurons, for example—that turn "off" and "on" repeatedly. Their findings are highlighted in the latest issue of Physical Review Letters.

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original publication : http://prl.aps.org/abstract/PRL/v110/i20/e204101

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## Geoffrey West: The surprising math of cities and corporations | Video on TED.com

Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population.
Bernard Ryefield's insight:

Geoffrey Brian West (born 1940 in Taunton, Somerset) is a British theoretical physicist, former president and distinguished professor of the Santa Fe Institute. He is one of the leading scientists working on a scientific model of cities. Among other things his work states that with the doubling of a city's size, services per capita will generally increase by 15%

http://en.wikipedia.org/wiki/Geoffrey_West

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## Steven Strogatz on sync | Video on TED.com

Mathematician Steven Strogatz shows how flocks of creatures (like birds, fireflies and fish) manage to synchronize and act as a unit -- when no one's giving orders. The powerful tendency extends into the realm of objects, too.
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## Center for the Study of Complex Systems | University of Michigan

The Center for the Study of Complex Systems (CSCS) is a broadly interdisciplinary program in the College of Literature, Science and the Arts (LSA) at the University of Michigan in Ann Arbor, Michigan. Our mission is to encourage and facilitate research and education in the general area of nonlinear, dynamical and adaptive systems.

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