See on Scoop.it – real utopias
One of the nation’s leading economists is calling for a comprehensive overhaul of the US economy.
See on Scoop.it – real utopias
One of the nation’s leading economists is calling for a comprehensive overhaul of the US economy.
An important challenge in several disciplines is to understand how sudden changes can propagate among coupled systems. Examples include the synchronization of business cycles, population collapse in patchy ecosystems, markets shifting to a new technology platform, collapses in prices and in confidence in financial markets, and protests erupting in multiple countries. A number of mathematical models of these phenomena have multiple equilibria separated by saddle-node bifurcations. We study this behaviour in its normal form as fast–slow ordinary differential equations. In our model, a system consists of multiple subsystems, such as countries in the global economy or patches of an ecosystem. Each subsystem is described by a scalar quantity, such as economic output or population, that undergoes sudden changes via saddle-node bifurcations. The subsystems are coupled via their scalar quantity (e.g. trade couples economic output; diffusion couples populations); that coupling moves the locations of their bifurcations. The model demonstrates two ways in which sudden changes can propagate: they can cascade (one causing the next), or they can hop over subsystems. The latter is absent from classic models of cascades. For an application, we study the Arab Spring protests. After connecting the model to sociological theories that have bistability, we use socioeconomic data to estimate relative proximities to tipping points and Facebook data to estimate couplings among countries. We find that although protests tend to spread locally, they also seem to ‘hop’ over countries, like in the stylized model; this result highlights a new class of temporal motifs in longitudinal network datasets.
Coupled catastrophes: sudden shifts cascade and hop among interdependent systems
Charles D. Brummitt, George Barnett, Raissa M. D’Souza
See on Scoop.it – Brain Tricks: Belief, Bias, and Blindspots
Storytelling is an ancient art form, a means of human expression, a way to tell others about events through words and actions.
Large-scale protests occur frequently and sometimes overthrow entire political systems. Meanwhile, online social networks have become an increasingly common component of people’s lives. We present a large-scale longitudinal study that connects online social media behaviors to offline protest. Using almost 14 million geolocated tweets and data on protests from 16 countries during the Arab Spring, we show that increased coordination of messages on Twitter using specific hashtags is associated with increased protests the following day. The results also show that traditional actors like the media and elites are not driving the results. These results indicate social media activity correlates with subsequent large-scale decentralized coordination of protests, with important implications for the future balance of power between citizens and their states.
Online social networks and offline protest
Zachary C Steinert-Threlkeld, Delia Mocanu, Alessandro Vespignani and James Fowler
EPJ Data Science 2015, 4:19 http://dx.doi.org/10.1140/epjds/s13688-015-0056-y
See on Scoop.it – Fiscal Policy & Regulation
The UK Government must take note of the malaise at the heart of the business community
Psychologist Daniel Kahneman was the first to bring the notion that we have two distinct parts to our brain – System 1 and System 2 – into the mainstream, writes Jennie Sallows, head of insight at Kinetic.
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