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Kinetics of wealth and the Pareto law

Kinetics of wealth and the Pareto law | Papers | Scoop.it

An important class of economic models involve agents whose wealth changes due to transactions with other agents. Several authors have pointed out an analogy with kinetic theory, which describes molecules whose momentum and energy change due to interactions with other molecules. We pursue this analogy and derive a Boltzmann equation for the time evolution of the wealth distribution of a population of agents for the so-called Yard-Sale Model of wealth exchange. We examine the solutions to this equation by a combination of analytical and numerical methods and investigate its long-time limit. We study an important limit of this equation for small transaction sizes and derive a partial integrodifferential equation governing the evolution of the wealth distribution in a closed economy. We then describe how this model can be extended to include features such as inflation, production, and taxation. In particular, we show that the model with taxation exhibits the basic features of the Pareto law, namely, a lower cutoff to the wealth density at small values of wealth, and approximate power-law behavior at large values of wealth.


Kinetics of wealth and the Pareto law
Phys. Rev. E 89, 042804 – Published 8 April 2014
Bruce M. Boghosian

http://dx.doi.org/10.1103/PhysRevE.89.042804


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One rule of life: Are we poised on the border of order?

WHEN physicists take an interest in the living world, some biologists fear the worst. After all, goes the bad joke, there's only so much you can gain by modelling a cow as a sphere. But one crucial idea from physics may hold valuable insights into complex biological behaviour in everything from birds to gene networks. There is increasing evidence that many systems we observe in living things are close to what's called a critical point – they sit on a knife-edge, precariously poised between order and disorder. Odd as it may sound, this strategy could confer a variety of benefits, in particular the flexibility to deal with a complex and unpredictable environment.


http://www.newscientist.com/article/mg22229660.700-one-rule-of-life-are-we-poised-on-the-border-of-order.html 


Draft at http://philipball.blogspot.mx/2014/04/criticality-and-phase-transitions-in.html


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Eli Levine's curator insight, May 4, 12:14 AM

Indeed, what is biology but a manifestation of physical laws and matter?

 

Makes sense to me, very much like it makes sense to have physicists look at the principles underpinning societies, markets and organizations of people.

Think about it.

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Impossible Cookware and Other Triumphs of the Penrose Tile

Impossible Cookware and Other Triumphs of the Penrose Tile | Papers | Scoop.it

Nobody knows how the story of forbidden symmetry ends. Mathematicians continue to explore the properties of Penrose tiles. Quasicrystals remain the subject of both basic and applied research. But it has been an incredible journey so far. In the past 40 years, five-axis symmetry has gone from impractical to valuable, from unnatural to perfectly natural, from forbidden to mainstream. It’s a transformation for which we can thank two scientists who pushed past conventional wisdom to uncover a remarkable new form of infinite variation in nature.


http://nautil.us/issue/13/symmetry/impossible-cookware-and-other-triumphs-of-the-penrose-tile

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Eli Levine's curator insight, May 2, 10:44 AM

Indeed, what is history, but the near repeating patterns of events, brought on by a complicated set of pre-conditions and pre-dispositions?  History, like Penrose Tiles, never quite entirely repeats and, true to quantum mechanics, it changes with observation, especially by people who wield power, control and influence in our world.  Very interesting that these patterns may also exist in our social worlds as well.

 

Think about it.

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Inferring human mobility using communication patterns

Understanding the patterns of mobility of individuals is crucial for a number of reasons, from city planning to disaster management. There are two common ways of quantifying the amount of travel between locations: by direct observations that often involve privacy issues, e.g., tracking mobile phone locations, or by estimations from models. Typically, such models build on accurate knowledge of the population size at each location. However, when this information is not readily available, their applicability is rather limited. As mobile phones are ubiquitous, our aim is to investigate if mobility patterns can be inferred from aggregated mobile phone call data. Using data released by Orange for Ivory Coast, we show that human mobility is well predicted by a simple model based on the frequency of mobile phone calls between two locations and their geographical distance. We argue that the strength of the model comes from directly incorporating the social dimension of mobility. Furthermore, as only aggregated call data is required, the model helps to avoid potential privacy problems.


Inferring human mobility using communication patterns
Vasyl Palchykov, Marija Mitrović, Hang-Hyun Jo, Jari Saramäki, Raj Kumar Pan

http://arxiv.org/abs/1404.7675

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Decision accuracy in complex environments is often maximized by small group sizes

Individuals in groups, whether composed of humans or other animal species, often make important decisions collectively, including avoiding predators, selecting a direction in which to migrate and electing political leaders. Theoretical and empirical work suggests that collective decisions can be more accurate than individual decisions, a phenomenon known as the ‘wisdom of crowds’.

[...] Our results demonstrate that the conventional view of the wisdom of crowds may not be informative in complex and realistic environments, and that being in small groups can maximize decision accuracy across many contexts.

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AbbVie Scoop.it Home Page's curator insight, May 1, 9:26 AM

The Couzin lab (Princeton) is focused on 'group animal behavior,' and although this paper isn't available directly, the title made me wonder if the observations might apply to the way we make decisions in what is certainly a complex environment...  Perhaps worth a read...

Damien Thouvenin's curator insight, May 3, 5:58 AM

Deux chercheurs de l'université de Princeton démontent la soi-disant "sagesse des foules" et montrent que, si l'intelligence collective d'un petit groupe produit de meilleurs résultats que le travail individuel, ceci est en revanche faut pour de grands groupes. La diversité des points de vue et des sensibilités d'un petit groupe tend à filtrer le "bruit" environnant tandis qu'il est amplifié par une foule.

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Evolution of acquired resistance to anti-cancer therapy

Here we review recent advances towards elucidating the evolutionary dynamics of acquired drug resistance and outline how evolutionary thinking can contribute to outstanding questions in the field.

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RISK OF WAR: WHAT, IF THE "BALANCE OF THREAT" IS UNSTABLE?

(...) The worrisome misconception is that only shifts in relative power can destabilize a “balance of threat”. This falsely assumes that balanced situations, called equilibria, are inherently stable, which is actually often not the case. For illustration, consider the simple experiment of a circular vehicle flow (see http://www.youtube.com/watch?v=Suugn-p5C1M ): although it is apparently not difficult to drive a car at constant speed together with other cars, the equilibrium traffic flow will break down sooner or later. If only the density on the traffic circle is higher than a certain value, a so-called "phantom traffic jam" will form without any particular reason – no accident, no obstacles, nothing. The lesson here is that dynamical systems can easily get out of control even if everyone has good information, the latest technology and best intentions.

What if this is similarly true for the balance of threat? What if this equilibrium is unstable? Then, it could suddenly and unexpectedly break down. (...)


RISK OF WAR: WHAT, IF THE "BALANCE OF THREAT" IS UNSTABLE?

by Dirk Helbing (ETH Zurich)

http://futurict.blogspot.ch/2014/04/risk-of-war-what-if-balance-of-threat.html

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Eli Levine's curator insight, April 28, 8:19 PM

Indeed, I don't understand how Obama and his advisers think that challenging Russia or China is going to lead to positive results for either the US or for the whole of the world that we're apart of.

 

For example, it would have been better for us to have mediated the Ukrainian crisis, rather than throw down as a partisansky of Ukrainian-Ukraine against Russia.  It was a move that failed to grasp the complexity of the situation, and the legitimate concerns of the Russian people living in Ukraine and of the Russian state in Moscow.

 

Over on the other side of Asia, our increased military alliance with the Philippines might also lead to problems for us in the long term.  Our first priority, I think, should be the defense of our homeland, not the protection of our imperial assets.  We should be finding out what the people of the Philippines want and need, along with the people of all countries that are currently in dispute with China over territorial waters and resources.  It is more important that we keep in touch with the societies, rather than the specific governments of these countries, and develop methods to directly arm them in case of Chinese attack.  That way, we can defend the people of these countries from Chinese attack, while maintaining good relations with them, thus, adding to our influence more than through direct military engagement with China.

 

It's just a few thoughts on the matters.

 

One small slip from us or any of the other actors, and the whole of civilization as we know it goes up in smoke.

That, or our species dies.

 

Enjoy your night.


Think about it.

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Power from the oceans: Blue energy

Power from the oceans: Blue energy | Papers | Scoop.it

In theory, oceans could power the entire globe without adding any pollution to the atmosphere. And they could provide a more dependable source of electricity than the wind or sun. They are also geographically convenient: roughly 44% of the global population lives within 150 kilometres of the coastline.


http://www.nature.com/news/power-from-the-oceans-blue-energy-1.15045 

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Ants Swarm Like Brains Think

Ants Swarm Like Brains Think | Papers | Scoop.it

Both ants and brains actually rely on two types of feedback, held in a delicate balance: negative (or inhibitory) feedback, and positive (or excitatory) feedback. “Negative feedback tends to cause stability. Positive feedback tends to cause runaway behavior,” said Tomer Czaczkes, an ant biologist at the University of Regensburg in Germany. “These two simple rules make something very powerful.”


http://nautil.us/issue/12/feedback/ants-swarm-like-brains-think 

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Eli Levine's curator insight, May 1, 10:14 AM

Small changes in behavior, thought or action can lead to dramatic changes, in time and with persistence, in the overall quality and function of the brain.

 

Imagine if we worked to heal each other and ourselves of our delusions, illusions, false perceptions, misconceptions, anger, depression, anxiety, etc?  What if we invented machines that could help us correct our brains' function, must like how we use glasses or hearing aids to correct our senses?

 

Consciousness must flow through the biological infrastructure of the brain.  You alter that in a majority of the people of this planet, you technically alter the entirety of the universe (although, I would add, that theoretically that higher level of conscious state had always been present, and that it is we who are arriving at it in our perceptions, while the essential universe itself remains unchanged).  This means that we'd simply be adapting to the universe in a more positive fashion, rather than actually altering it; conforming more to its natural law than shifting the paradigm of our existence on this planet, in this place.

 

Cool cool stuff here.

 

Think about it.

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Uncovering the structure and temporal dynamics of information propagation

Time plays an essential role in the diffusion of information, influence, and disease over networks. In many cases we can only observe when a node is activated by a contagion—when a node learns about a piece of information, makes a decision, adopts a new behavior, or becomes infected with a disease. However, the underlying network connectivity and transmission rates between nodes are unknown. Inferring the underlying diffusion dynamics is important because it leads to new insights and enables forecasting, as well as influencing or containing information propagation. In this paper we model diffusion as a continuous temporal process occurring at different rates over a latent, unobserved network that may change over time. Given information diffusion data, we infer the edges and dynamics of the underlying network. Our model naturally imposes sparse solutions and requires no parameter tuning. We develop an efficient inference algorithm that uses stochastic convex optimization to compute online estimates of the edges and transmission rates. We evaluate our method by tracking information diffusion among 3.3 million mainstream media sites and blogs, and experiment with more than 179 million different instances of information spreading over the network in a one-year period. We apply our network inference algorithm to the top 5,000 media sites and blogs and report several interesting observations. First, information pathways for general recurrent topics are more stable across time than for on-going news events. Second, clusters of news media sites and blogs often emerge and vanish in a matter of days for on-going news events. Finally, major events, for example, large scale civil unrest as in the Libyan civil war or Syrian uprising, increase the number of information pathways among blogs, and also increase the network centrality of blogs and social media sites.


Uncovering the structure and temporal dynamics of information propagation
MANUEL GOMEZ RODRIGUEZ, JURE LESKOVEC, DAVID BALDUZZI, BERNHARD SCHÖLKOPF
Network Science , Volume 2 , Issue 01 , April 2014, pp 26 - 65
http://dx.doi.org/10.1017/nws.2014.3 

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The Influence of Spatiotemporal Structure of Noisy Stimuli in Decision Making

The Influence of Spatiotemporal Structure of Noisy Stimuli in Decision Making | Papers | Scoop.it

Decision making is a process of utmost importance in our daily lives, the study of which has been receiving notable attention for decades. Nevertheless, the neural mechanisms underlying decision making are still not fully understood. Computational modeling has revealed itself as a valuable asset to address some of the fundamental questions. Biophysically plausible models, in particular, are useful in bridging the different levels of description that experimental studies provide, from the neural spiking activity recorded at the cellular level to the performance reported at the behavioral level. In this article, we have reviewed some of the recent progress made in the understanding of the neural mechanisms that underlie decision making. We have performed a critical evaluation of the available results and address, from a computational perspective, aspects of both experimentation and modeling that so far have eluded comprehension. To guide the discussion, we have selected a central theme which revolves around the following question: how does the spatiotemporal structure of sensory stimuli affect the perceptual decision-making process? This question is a timely one as several issues that still remain unresolved stem from this central theme. These include: (i) the role of spatiotemporal input fluctuations in perceptual decision making, (ii) how to extend the current results and models derived from two-alternative choice studies to scenarios with multiple competing evidences, and (iii) to establish whether different types of spatiotemporal input fluctuations affect decision-making outcomes in distinctive ways. And although we have restricted our discussion mostly to visual decisions, our main conclusions are arguably generalizable; hence, their possible extension to other sensory modalities is one of the points in our discussion.


Insabato A, Dempere-Marco L, Pannunzi M, Deco G, Romo R (2014) The Influence of Spatiotemporal Structure of Noisy Stimuli in Decision Making. PLoS Comput Biol 10(4): e1003492. http://dx.doi.org/10.1371/journal.pcbi.1003492 

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Social cycling and conditional responses in the Rock-Paper-Scissors game

How humans make decisions in non-cooperative strategic interactions is a challenging question. For the fundamental model system of Rock-Paper-Scissors (RPS) game, classic game theory of infinite rationality predicts the Nash equilibrium (NE) state with every player randomizing her choices to avoid being exploited, while evolutionary game theory of bounded rationality in general predicts persistent cyclic motions, especially for finite populations. However, as empirical studies on human subjects have been relatively sparse, it is still a controversial issue as to which theoretical framework is more appropriate to describe decision making of human subjects. Here we observe population-level cyclic motions in a laboratory experiment of the discrete-time iterated RPS game under the traditional random pairwise-matching protocol. The cycling direction and frequency are not sensitive to the payoff parameter a. This collective behavior contradicts with the NE theory but it is quantitatively explained by a microscopic model of win-lose-tie conditional response without any adjustable parameter. Our theoretical calculations reveal that this new strategy may offer higher payoffs to individual players in comparison with the NE mixed strategy, suggesting that high social efficiency is achievable through optimized conditional response.


Social cycling and conditional responses in the Rock-Paper-Scissors game
Zhijian Wang, Bin Xu, Hai-Jun Zhou

http://arxiv.org/abs/1404.5199

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Synthetic biology: Biocircuits in synchrony

Synthetic biology: Biocircuits in synchrony | Papers | Scoop.it

A major goal of synthetic biology is to build reliable, predictable networks of molecular and cellular components that can work as new biological devices capable of, for example, sensing chemicals, manufacturing drugs or even fighting disease. However, achieving such goals entails the production of complex synthetic biocircuits, which requires synchronization of multiple components. Although synchronization is well established in electronics1, synchronizing living cells is a major challenge, because it demands correlation of different phenomena that may be taking place on different temporal and spatial scales. (...) Prindle et al. report that such coupling has been achieved in cells of the bacterium Escherichia coli.


Synthetic biology: Biocircuits in synchrony
Ricard Solé & Javier Macía

Nature (2014)

http://dx.doi.org/10.1038/nature13224 ;


Rapid and tunable post-translational coupling of genetic circuits
Arthur Prindle, Jangir Selimkhanov, Howard Li, Ivan Razinkov, Lev S. Tsimring & Jeff Hasty
Nature (2014)

http://dx.doi.org/10.1038/nature13238

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Networks in financial markets based on the mutual information rate

Networks in financial markets based on the mutual information rate | Papers | Scoop.it

In the last few years there have been many efforts in econophysics studying how network theory can facilitate understanding of complex financial markets. These efforts consist mainly of the study of correlation-based hierarchical networks. This is somewhat surprising as the underlying assumptions of research looking at financial markets are that they are complex systems and thus behave in a nonlinear manner, which is confirmed by numerous studies, making the use of correlations which are inherently dealing with linear dependencies only baffling. In this paper we introduce a way to incorporate nonlinear dynamics and dependencies into hierarchical networks to study financial markets using mutual information and its dynamical extension: the mutual information rate. We show that this approach leads to different results than the correlation-based approach used in most studies, on the basis of 91 companies listed on the New York Stock Exchange 100 between 2003 and 2013, using minimal spanning trees and planar maximally filtered graphs.


DOI: http://dx.doi.org/10.1103/PhysRevE.89.052801

Networks in financial markets based on the mutual information rate
Phys. Rev. E 89, 052801 – Published 1 May 2014
Paweł Fiedor


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Driving Interconnected Networks to Supercriticality

Driving Interconnected Networks to Supercriticality | Papers | Scoop.it

“Going viral” is a familiar phrase in the world of social media, but fundamental scientific understanding of the mechanism(s) of “viral” spreading in interconnected multilayer networks is very limited. A new statistical-physics study reveals when and how fast spreading results from correlation between lateral (intralayer) and vertical (interlayer) spreading.


Driving Interconnected Networks to Supercriticality
Filippo Radicchi
Phys. Rev. X 4, 021014 (2014)

http://dx.doi.org/10.1103/PhysRevX.4.021014

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Social Evolution: New Horizons

Cooperation is a widespread natural phenomenon yet current evolutionary thinking is dominated by the paradigm of selfish competition. Recent advanced in many fronts of Biology and Non-linear Physics are helping to bring cooperation to its proper place. In this contribution, the most important controversies and open research avenues in the field of social evolution are reviewed. It is argued that a novel theory of social evolution must integrate the concepts of the science of Complex Systems with those of the Darwinian tradition. Current gene-centric approaches should be reviewed and complemented with evidence from multilevel phenomena (group selection), the constrains given by the non-linear nature of biological dynamical systems and the emergent nature of dissipative phenomena.


Social Evolution: New Horizons
Octavio Miramontes, Og DeSouza

http://arxiv.org/abs/1404.6267

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june holley's curator insight, May 3, 7:31 AM

Fascinating article suggesting a new evolutionary theory that recognizes the critical importance of cooperation and mutualism.

Jose Ali Vivas's curator insight, May 3, 9:56 AM

Cooperation is a widespread natural phenomenon... sure!

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A spatial microsimulation approach for the analysis of commuter patterns: from individual to regional levels

A spatial microsimulation approach for the analysis of commuter patterns: from individual to regional levels | Papers | Scoop.it

The daily trip to work is ubiquitous, yet its characteristics differ widely from person to person and place to place. This is manifested in statistics on mode and distance of travel, which vary depending on a range of factors that operate at different scales. This heterogeneity is problematic for decision makers tasked with encouraging more sustainable commuter patterns. Numerical models, based on real commuting data, have great potential to aid the decision making process. However, we contend that new approaches are needed to advance knowledge about the social and geographical factors that relate to the diversity of commuter patterns, if policies targeted to specific individuals or places are to be effective. To this end, the paper presents a spatial microsimulation approach, which combines individual-level survey data with geographically aggregated census results to tackle the problem. This method overcomes the limitations imposed by the lack of available geocoded micro-data. Further, it allows a range of scales of analysis to be pursued in parallel and provides insights into both the types of area and individual that would benefit most from specific interventions.


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Investment in higher order central processing regions is not constrained by brain size in social insects

The extent to which size constrains the evolution of brain organization and the genesis of complex behaviour is a central, unanswered question in evolutionary neuroscience.

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Markers of criticality in phase synchronisation

The concept of the brain as a critical system is very attractive because systems close to criticality are thought to maximise their dynamic range of information processing and communication. To date, there have been two key experimental observations supporting this hypothesis: i) neuronal avalanches with power law distribution of size and ii) long-range temporal correlations (LRTCs) in the amplitude of neural oscillations. The case for how these maximise dynamic range of information processing and communication is still being made and because a significant substrate for information coding and transmission is neural synchrony it is of interest to link synchronisation measures with those of criticality. We propose a framework for characterising criticality in synchronisation based on a new metric of phase synchronisation (rate of change of phase difference) and a set of methods we have developed for detecting LRTCs. We test this framework against two classical models of criticality (Ising and Kuramoto) and recently described variants of these models aimed to more closely represent human brain dynamics. From these simulations we determine the parameters at which these systems show evidence of LRTCs in phase synchronisation. We demonstrate proof of principle by analysing pairs of human simultaneous EEG and EMG time series, suggesting that LRTCs of corticomuscular phase synchronisation can be detected in the resting state. The existence of LRTCs in fluctuations of phase synchronisation suggests that these fluctuations are governed by non-local behaviour. This has important implications regarding the conditions under which one should expect to see LRTCs in phase synchronisation. Specifically, brain resting states may exhibit LRTCs reflecting a state of readiness facilitating rapid task-dependent shifts towards and away from synchronous states that abolish LRTCs.


Markers of criticality in phase synchronisation
Maria Botcharova, Simon F. Farmer, Luc Berthouze

http://arxiv.org/abs/1404.5774

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Obesity

Obesity | Papers | Scoop.it

The best way to lose weight is to eat less and exercise more. But as a strategy to combat obesity at the population level, this common-sense prescription is proving ineffective over the long term. Tailored treatment programmes that factor in the stresses and temptations of the real world, using insights from behavioural research, are showing some success. Drugs may also form part of the solution. Or perhaps the pharmaceutical option should be a last resort, and society should instead use the power of government regulation to encourage healthier lifestyle options.


Obesity
• Tony Scully
Nature 508, S49 (17 April 2014) http://dx.doi.org/10.1038/508S49a

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Biological hypercomputation: A new research problem in complexity theory

This article discusses the meaning and scope of biological hypercomputation (BH) that is to be considered as new research problem within the sciences of complexity. The framework here is computational, setting out that life is not a standard Turing Machine. Living systems, we claim, hypercompute, and we aim at understanding life not by what it is, but rather by what it does. The distinction is made between classical and nonclassical hypercomputation. We argue that living processes are nonclassical hypercomputation. BH implies then new computational models. Finally, we sketch out the possibilities, stances, and reach of BH. 


Biological hypercomputation: A new research problem in complexity theory
. Carlos E. Maldonado and Nelson A. Gómez Cruz

Complexity

http://dx.doi.org/10.1002/cplx.21535 

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Career on the Move: Geography, Stratification, and Scientific Impact

Changing institutions is an integral part of an academic life. Yet little is known about the mobility patterns of scientists at an institutional level and how these career choices affect scientific outcomes. Here, we examine over 420,000 papers, to track the affiliation information of individual scientists, allowing us to reconstruct their career trajectories over decades. We find that career movements are not only temporally and spatially localized, but also characterized by a high degree of stratification in institutional ranking. When cross-group movement occurs, we find that while going from elite to lower-rank institutions on average associates with modest decrease in scientific performance, transitioning into elite institutions does not result in subsequent performance gain. These results offer empirical evidence on institutional level career choices and movements and have potential implications for science policy.


Career on the Move: Geography, Stratification, and Scientific Impact
• Pierre Deville, Dashun Wang, Roberta Sinatra, Chaoming Song, Vincent D. Blondel & Albert-László Barabási

Scientific Reports 4, Article number: 4770 http://dx.doi.org/10.1038/srep04770

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Resilience of modular complex networks

Complex networks often have a modular structure, where a number of tightly- connected groups of nodes (modules) have relatively few interconnections. Modularity had been shown to have an important effect on the evolution and stability of biological networks, on the scalability and efficiency of large-scale infrastructure, and the development of economic and social systems. An analytical framework for understanding modularity and its effects on network vulnerability is still missing. Through recent advances in the understanding of multilayer networks, however, it is now possible to develop a theoretical framework to systematically study this critical issue. Here we study, analytically and numerically, the resilience of modular networks under attacks on interconnected nodes, which exhibit high betweenness values and are often more exposed to failure. Our model provides new understandings into the feedback between structure and function in real world systems, and consequently has important implications as diverse as developing efficient immunization strategies, designing robust large-scale infrastructure, and understanding brain function.


Resilience of modular complex networks
Saray Shai, Dror Y. Kenett, Yoed N. Kenett, Miriam Faust, Simon Dobson, Shlomo Havlin

http://arxiv.org/abs/1404.4748

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Power-law distributions in binned empirical data

Many man-made and natural phenomena, including the intensity of earthquakes, population of cities and size of international wars, are believed to follow power-law distributions. The accurate identification of power-law patterns has significant consequences for correctly understanding and modeling complex systems. However, statistical evidence for or against the power-law hypothesis is complicated by large fluctuations in the empirical distribution's tail, and these are worsened when information is lost from binning the data. We adapt the statistically principled framework for testing the power-law hypothesis, developed by Clauset, Shalizi and Newman, to the case of binned data. This approach includes maximum-likelihood fitting, a hypothesis test based on the Kolmogorov--Smirnov goodness-of-fit statistic and likelihood ratio tests for comparing against alternative explanations. We evaluate the effectiveness of these methods on synthetic binned data with known structure, quantify the loss of statistical power due to binning, and apply the methods to twelve real-world binned data sets with heavy-tailed patterns.


Power-law distributions in binned empirical data
Yogesh Virkar, Aaron Clauset

http://arxiv.org/abs/1208.3524

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The infection tree of global epidemics

The spreading of transmissible infectious diseases is inevitably entangled with the dynamics of human population. Humans are the carrier of the pathogen, and the large-scale travel and commuting patterns that govern the mobility of modern societies are defining how epidemics and pandemics travel across the world. For a long time, the development of quantitative spatially explicit models able to shed light on the global dynamics of pandemic has been limited by the lack of detailed data on human mobility. In the last 10 years, however, these limits have been lifted by the increasing availability of data generated by new information technologies, thus triggering the development of computational (microsimulation) models working at a level of single individuals in spatially extended regions of the world. Microsimulations can provide information at very detailed spatial resolutions and down to the level of single individuals. In addition, computational implementations explicitly account for stochasticity, allowing the study of multiple realizations of epidemics with the same parameters' distribution. While on the one hand these capabilities represent the richness of microsimulation methods, on the other hand they face us with a huge amount of information that requires the use of specific data reduction methods and visual analytics.


The infection tree of global epidemics
ANA PASTORE Y PIONTTI, MARCELO FERREIRA DA COSTA GOMES, NICOLE SAMAY, NICOLA PERRA and ALESSANDRO VESPIGNANI

Network Science
http://dx.doi.org/10.1017/nws.2014.5


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