Papers
565.7K views | +5 today
Follow
 
Scooped by Complexity Digest
onto Papers
Scoop.it!

Cross-checking different sources of mobility information

The pervasive use of new mobile devices has allowed a better characterization in space and time of human concentrations and mobility in general. Besides its theoretical interest, describing mobility is of great importance for a number of practical applications ranging from the forecast of disease spreading to the design of new spaces in urban environments. While classical data sources, such as surveys or census, have a limited level of geographical resolution (e.g., districts, municipalities, counties are typically used) or are restricted to generic workdays or weekends, the data coming from mobile devices can be precisely located both in time and space. Most previous works have used a single data source to study human mobility patterns. Here we perform instead a cross-check analysis by comparing results obtained with data collected from three different sources: Twitter, census and cell phones. The analysis is focused on the urban areas of Barcelona and Madrid, for which data of the three types is available. We assess the correlation between the datasets on different aspects: the spatial distribution of people concentration, the temporal evolution of people density and the mobility patterns of individuals. Our results show that the three data sources are providing comparable information. Even though the representativeness of Twitter geolocated data is lower than that of mobile phone and census data, the correlations between the population density profiles and mobility patterns detected by the three datasets are close to one in a grid with cells of 2x2 and 1x1 square kilometers. This level of correlation supports the feasibility of interchanging the three data sources at the spatio-temporal scales considered.


Cross-checking different sources of mobility information
Maxime Lenormand, Miguel Picornell, Oliva G. Cantu-Ros, Antonia Tugores, Thomas Louail, Ricardo Herranz, Marc Barthelemy, Enrique Frias-Martinez, Jose J. Ramasco

http://arxiv.org/abs/1404.0333

No comment yet.
Papers
Recent publications related to complex systems
Your new post is loading...
Your new post is loading...
Scooped by Complexity Digest
Scoop.it!

[Classics] Principles of the self-organizing system

W. Ross Ashby

The brilliant British psychiatrist, neuroscientist, and mathematician Ross Ashby was one of the pioneers in early and mid-phase cybernetics and thereby one of the leading progenitors of modern complexity theory. Not one to take either commonly used terms or popular notions for granted, Ashby probed deeply into the meaning of supposedly self-organizing systems. At the time of the following article, he had been working on a mathematical formalism of his homeostat, a hypothetical machine established on an axiomatic, set theoretical foundation that was supposed to offer a sufficient description of a living organism’s learning and adaptive intelligence. Ashby’s homeostat had a small number of essential variables serving to maintain its operation over a wide range of environmental conditions so that if the latter changed and thereby shifted the variables beyond the range where the homeostat could safely function, a new ‘higher’ level of the machine was activated in order to randomly reset the lower level’s internal connections or organization (see Dupuy, 2000). Like the role of random mutations during evolution, if the new range set at random proved functional, the homeostat survived, otherwise it expired.

One of Ashby’s goals was to repudiate that interpretation of the notion of self-organization, one commonly held to this day, which would have it that either a machine or a living organism could by itself change its own organization (or, in his phraseology, the functional mappings). For Ashby, self-organization in this sense was a bit of superfluous metaphysics since he believed not only could his formalism by itself completely delineate the homeostat’s lower level organization, the adaptive novelty of his homeostat was purely the result of its upper level randomization that could reorganize the lower level and not some innate propensity for autonomous change. We offer Ashby’s careful reasoning here as an enlightening guide for coming to terms with key ideas in complexity theory whose genuine significance lies less with facile bandying about and more with an intensive and extensive examination of the underlying assumptions.

Read the full article at: journal.emergentpublications.com

Also at http://femto4.chem.elte.hu/entropia/InfoTheoryPapers/Ashby1962.pdf 

No comment yet.
Scooped by Complexity Digest
Scoop.it!

The TAP equation: evaluating combinatorial innovation

Marina Cortês, Stuart A. Kauffman, Andrew R. Liddle, Lee Smolin
We investigate solutions to the TAP equation, a phenomenological implementation of the Theory of the Adjacent Possible. Several implementations of TAP are studied, with potential applications in a range of topics including economics, social sciences, environmental change, evolutionary biological systems, and the nature of physical laws. The generic behaviour is an extended plateau followed by a sharp explosive divergence. We find accurate analytic approximations for the blow-up time that we validate against numerical simulations, and explore the properties of the equation in the vicinity of equilibrium between innovation and extinction. A particular variant, the two-scale TAP model, replaces the initial plateau with a phase of exponential growth, a widening of the TAP equation phenomenology that may enable it to be applied in a wider range of contexts.

Read the full article at: arxiv.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

How an information perspective helps overcome the challenge of biology to physics

How an information perspective helps overcome the challenge of biology to physics | Papers | Scoop.it

Keith D.Farnsworth

Biosystems
Volume 217, July 2022, 104683

Living systems have long been a puzzle to physics, leading some to claim that new laws of physics are needed to explain them. Separating physical reality into the general (laws) and the particular (location of particles in space and time), it is possible to see that the combination of these amounts to efficient causation, whereby forces are constrained by patterns that constitute embodied information which acts as formal cause. Embodied information can only be produced by correlation with existing patterns, but sets of patterns can be arranged to form reflexive relations in which constraints on force are themselves formed by the pattern that results from action of those same constrained forces. This inevitably produces a higher level of pattern which reflexively reinforces itself. From this, multi-level hierarchies and downward causation by information are seen to be patterns of patterns that constrain forces. Such patterns, when causally cyclical, are closed to efficient causation. But to be autonomous, a system must also have its formative information accumulated by repeated cycles of selection until sufficient is obtained to represent the information content of the whole (which is the essential purpose of information oligomers such as DNA). Living systems are the result of that process and therefore cannot exist unless they are both closed to efficient causation and capable of embodying an independent supply of information sufficient to constitute their causal structure. Understanding this is not beyond the scope of standard physics, but it does recognise the far greater importance of information accumulation in living than in non-living systems and, as a corollary, emphasises the dependence of biological systems on the whole history of life, leading up to the present state of any and all organisms.

Read the full article at: www.sciencedirect.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Sustainability and Goal Fitness Index for the Analysis of Sustainable Development Goals: A Methodological Proposal

Sustainability and Goal Fitness Index for the Analysis of Sustainable Development Goals: A Methodological Proposal | Papers | Scoop.it

Sanny González, Gabriel Pereira, and Arturo González

The Sustainable Development Goals (SDGs) were adopted in September 2015 by the 193 member states of the United Nations (UN), which include 17 goals, 169 targets and 244 indicators, as an attempt to radically change the approach of the Millennium Development Goals (MDGs). Since the adoption of the 2030 Agenda, the scientific community has increased its interest in the evaluation, analysis, and evaluation of the interrelationships between the SDGs, proposing different approaches and using a diversity of methodological tools for the interactions of the SDGs. This research proposes a methodology that takes advantage of the concepts of Economic Fitness for the creation of a Sustainability Fitness Index (SFI) for the countries and a Goal Fitness Index (GFI) for each SDG. These indices are intended to provide a tool to analyze the interrelationships between the Sustainable Development Goals in such a way that they offer a new approach to address the capacities of the countries and the fulfillment of the SDGs. The results of the SFI are a first attempt to identify development priorities aligned with the SDGs in each country, based on their available productive capacities, which could help make more efficient use of their limited resources and increase the achievement of the SDGs.

Read the full article at: www.scitepress.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

The universality in urban commuting across and within cities

Lei Dong, Paolo Santi, Yu Liu, Siqi Zheng, Carlo Ratti
Commuting is a key mechanism that governs the dynamics of cities. Despite its importance, very little is known of the properties and mechanisms underlying this crucial urban process. Here, we capitalize on ∼ 50 million individuals' smartphone data from 234 Chinese cities to show that urban commuting obeys remarkable regularities. These regularities can be generalized as two laws: (i) the scale-invariance of the average commuting distance across cities, which is a long-awaited validation of Marchetti's constant conjecture, and (ii) a universal inverted U-shape of the commuting distance as a function of the distance from the city centre within cities, indicating that the city centre's attraction is bounded. Motivated by such empirical findings, we develop a simple urban growth model that connects individual-level mobility choices with macroscopic urban spatial structure and faithfully explains both commuting laws. Our results further show that the scale-invariants of human mobility will ultimately lead to the polycentric transition in cities, which could be used to better inform urban development strategies.

Read the full article at: arxiv.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

[Classics] More Is Different: Broken symmetry and the nature of the hierarchical structure of science.

[Classics] More Is Different: Broken symmetry and the nature of the hierarchical structure of science. | Papers | Scoop.it

P. W. ANDERSON
SCIENCE • 4 Aug 1972 • Vol 177, Issue 4047 • pp. 393-396

Read the full article at: www.science.org

No comment yet.
Suggested by Takaya Arita
Scoop.it!

Evolution of metamemory based on self-reference to own memory in artificial neural network with neuromodulation

Evolution of metamemory based on self-reference to own memory in artificial neural network with neuromodulation | Papers | Scoop.it

Yusuke Yamato, Reiji Suzuki & Takaya Arita
Scientific Reports volume 12, Article number: 6233 (2022)

The ability of humans to self-monitor and control their memory processes is called metamemory and has been widely studied as a component of metacognition in cognitive psychology. Metamemory in non-human animals has also been investigated in recent years, although it had been regarded as a truly unique characteristic of human memory. We attempt to evolve artificial neural networks with neuromodulation, which have a metamemory function. Our constructive approach is expected to contribute, by introducing a novel dimension of evolutionary plausibility, to the discussion of animal experiments to detect metamemory. In this study, we demonstrate the evolution of neural networks that have a metamemory function based on the self-reference of memory, including the analysis of the evolved mechanism of metamemory. In addition, we discuss the similarity between the structure of the evolved neural network and the metamemory model defined by Nelson and Narens.

Read the full article at: www.nature.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Biocosmology: Biology from a cosmological perspective

Marina Cortês, Stuart A. Kauffman, Andrew R. Liddle, Lee Smolin
The Universe contains everything that exists, including life. And all that exists, including life, obeys universal physical laws. Do those laws then give adequate foundations for a complete explanation of biological phenomena? We discuss whether and how cosmology and physics must be modified to be able to address certain questions which arise at their intersection with biology. We show that a universe that contains life, in the form it has on Earth, is in a certain sense radically non-ergodic, in that the vast majority of possible organisms will never be realized. We argue from this that complete explanations in cosmology require a mixture of reductionist and functional explanations.

Read the full article at: arxiv.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

A Short Tutorial on Mean-Field Spin Glass Techniques for Non-Physicists

Andrea Montanari, Subhabrata Sen
This tutorial is based on lecture notes written for a class taught in the Statistics Department at Stanford in the Winter Quarter of 2017. The objective was to provide a working knowledge of some of the techniques developed over the last 40 years by theoretical physicists and mathematicians to study mean field spin glasses and their applications to high-dimenensional statistics and statistical learning.

Read the full article at: arxiv.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

The biosphere computes evolution by autoencoding interacting organisms into species and decoding species into ecosystems

Irun R. Cohen, Assaf Marron
Autoencoding is a machine-learning technique for extracting a compact representation of the essential features of input data; this representation then enables a variety of applications that rely on encoding and subsequent reconstruction based on decoding of the relevant data. Here, we document our discovery that the biosphere evolves by a natural process akin to computer autoencoding. We establish the following points: (1) A species is defined by its species interaction code. The species code consists of the fundamental, core interactions of the species with its external and internal environments; core interactions are encoded by multi-scale networks including molecules-cells-organisms. (2) Evolution expresses sustainable changes in species interaction codes; these changing codes both map and construct the species environment. The survival of species is computed by what we term \textit{natural autoencoding}: arrays of input interactions generate species codes, which survive by decoding into sustained ecosystem interactions. This group process, termed survival-of-the-fitted, supplants the Darwinian struggle of individuals and survival-of-the-fittest only. DNA is only one element in natural autoencoding. (3) Natural autoencoding and artificial autoencoding techniques manifest defined similarities and differences. Biosphere autoencoding and survival-of-the-fitted sheds a new light on the mechanism of evolution. Evolutionary autoencoding renders evolution amenable to new approaches to computer modeling.

Read the full article at: arxiv.org

No comment yet.
Suggested by Klaus jaffe
Scoop.it!

Constitutions, rule of law, socioeconomics… and populism

Canova, Antonio and Martinez, Edrey and Soares, Ana Cecilia and Scolaro, Mariana and Jaffe, Klaus

Is it possible to know how institutionally stable a country is, how corrupt its rulers are, what is the expectation and standard of living of its inhabitants, how dynamic and complex is its economy, all this, just by identifying and counting certain words in its constitution? We tried to empirically measure the effect of constitutions –if any– on the institutionality and socioeconomics of a country. This study of the history of 88 countries confirms a relationship between quantitative aspects of the constitution and the institutional and socioeconomic well-being of the country; and that new constitutions, over time, tend to be more extensive, with more articles and words. We now know, from a qualitative analysis, that the number of populist words in new constitutions is also greater. We knew that there is a moderate correlation between extensive constitutions, weak rule of law, and low socioeconomic variables. And now we find a strong correlation between countries with even lower rule of law and socioeconomic indexes and constitutions with a higher percentage of populist words. In this correlational study we use 84 international indicators. We did not find a direct cause-effect relationship between a new constitution and subsequent changes in the country's socioeconomic variables, nor in institutional aspects. We do observe that the institutional and socioeconomic conditions of a country predict certain characteristics of a new constitution. There are objective differences between the constitutions of countries with the prosperity syndrome and the dysfunctional ones. For example, the evidence shows that countries with few populist words in their constitutions enjoy a prosperity syndrome, while countries with many populist words in their constitutions suffer from a dysfunctional syndrome. These results suggest that such syndromes reflect a synergistic relationship between various factors that define the success of countries. Many things are needed for a prosperous society and only a few for it to be dysfunctional. We have seen that constitutions are a factor in this entanglement of synergies and – yes – they must be taken into consideration. Deciphering the role of constitutions in this process needs further exploration and is beyond our current rational capacities. We introduce the Pop-Con Index, an objective indicator of constitutional populism in 88 countries.

Read the full article at: papers.ssrn.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Contrasting social and non-social sources of predictability in human mobility

Contrasting social and non-social sources of predictability in human mobility | Papers | Scoop.it

Zexun Chen, Sean Kelty, Alexandre G. Evsukoff, Brooke Foucault Welles, James Bagrow, Ronaldo Menezes & Gourab Ghoshal 
Nature Communications volume 13, Article number: 1922 (2022)

Social structures influence human behavior, including their movement patterns. Indeed, latent information about an individual’s movement can be present in the mobility patterns of both acquaintances and strangers. We develop a “colocation” network to distinguish the mobility patterns of an ego’s social ties from those not socially connected to the ego but who arrive at a location at a similar time as the ego. Using entropic measures, we analyze and bound the predictive information of an individual’s mobility pattern and its flow to both types of ties. While the former generically provide more information, replacing up to 94% of an ego’s predictability, significant information is also present in the aggregation of unknown colocators, that contain up to 85% of an ego’s predictive information. Such information flow raises privacy concerns: individuals sharing data via mobile applications may be providing actionable information on themselves as well as others whose data are absent.

Read the full article at: www.nature.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Complexity Research

Complexity Research | Papers | Scoop.it

Where do we come from? Where are we going? New research from the Santa Fe Institute explores key questions related to humanity, society, and the existence of life in our world.

Part 1: The Principles of Complexity: Understanding the Hidden Sources of Order by Dr. Stefani Crabtree

Part 2: Autocatalytic Sets: Complexity at the Interface of Chemistry and Biology by Dr. Wim Hordijk

Part 3: Beyond Pairwise: Higher-Order Interactions in Complex Systems

Read the full article at: www.templeton.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

‘Machine Scientists’ Distill the Laws of Physics From Raw Data

‘Machine Scientists’ Distill the Laws of Physics From Raw Data | Papers | Scoop.it

Researchers say we’re on the cusp of “GoPro physics,” where a camera can point at an event and an algorithm can identify the underlying physics equation.

Read the full article at: www.quantamagazine.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

[Classics] The Architecture of Complexity (1962)

Herbert A. Simon
Proceedings of the American Philosophical Society
Vol. 106, No. 6 (Dec. 12, 1962), pp. 467-482

A number of proposals have been advanced in recent years for the development of "general systems theory" which, abstracting from properties peculiar to physical, biological, or social systems, would be applicable to all of them. We might well feel that, while the goal is laudable, systems of such diverse kinds could hardly be expected to have any nontrivial properties in common. Metaphor and analogy can be helpful, or they can be misleading. All depends on whether the similarities the metaphor captures are significant or superficial.

Read the full article at: www.jstor.org

Also at https://www2.econ.iastate.edu/tesfatsi/ArchitectureOfComplexity.HSimon1962.pdf 

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Disentangling material, social, and cognitive determinants of human behavior and beliefs

Denis TverskoiAndrea GuidoGiulia AndrighettoAngel SánchezSergey Gavrilets

In social interactions, human decision-making, attitudes, and beliefs about others coevolve. Their dynamics are affected by cost-benefit considerations, cognitive processes (such as cognitive dissonance, social projecting, and logic constraints), and social influences by peers (via descriptive and injunctive social norms) and by authorities (e.g., educational, cultural, religious, political, administrative, individual or group, real or fictitious). Here we attempt to disentangle some of this complexity by using an integrative mathematical modeling and a 35-day online behavioral experiment. We utilize data from a Common Pool Resources experiment with or without messaging promoting a group-beneficial level of resource extraction. We first show that our model provides a better fit than a wide variety of alternative models. Then we directly estimate the weights of different factors in decision-making and beliefs dynamics. We show that material payoffs accounted only for about 20\% of decision-making. The remaining 80\% was due to different cognitive and social forces which we evaluated quantitatively. Without messaging, personal norms (and cognitive dissonance) have the largest weight in decision-making. Messaging greatly influences personal norms and normative expectations. Between-individual variation is present in all measured characteristics and notably impacts observed group behavior. At the same time, gender differences are not significant. We argue that one can hardly understand social behavior without understanding the dynamics of personal beliefs and beliefs about others and that cognitive, social, and material factors all play important roles in these processes. Our results have implications for understanding and predicting social processes triggered by certain shocks (e.g., social unrest, a pandemic, or a natural disaster) and for designing policy interventions aiming to change behavior (e.g. actions aimed at environment protection or climate change mitigation).

Read the full article at: osf.io

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Universality out of order

Universality out of order | Papers | Scoop.it

Petter Holme 

Nature Communications volume 13, Article number: 2355 (2022)

Orders, rankings, and hierarchies on one side, universal statistical laws on the other—it is rare that these core concepts of complex systems science meet. This Comment sets the scene for some recent discoveries in this too seldomly visited border zone.

Read the full article at: www.nature.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Instability of networks: effects of sampling frequency and extreme fluctuations in financial data

Instability of networks: effects of sampling frequency and extreme fluctuations in financial data | Papers | Scoop.it

Jalshayin Bhachech, Arnab Chakrabarti, Taisei Kaizoji & Anindya S. Chakrabarti 

The European Physical Journal B volume 95, Article number: 71 (2022)

What determines the stability of networks inferred from dynamical behavior of a system? Internal and external shocks in a system can destabilize the topological properties of comovement networks. In real-world data, this creates a trade-off between identification of turbulent periods and the problem of high dimensionality. Longer time-series reduces the problem of high dimensionality, but suffers from mixing turbulent and non-turbulent periods. Shorter time-series can identify periods of turbulence more accurately, but introduces the problem of high dimensionality, so that the underlying linkages cannot be estimated precisely. In this paper, we exploit high-frequency multivariate financial data to analyze the origin of instability in the inferred networks during periods free from external disturbances. We show that the topological properties captured via centrality ordering is highly unstable even during such non-turbulent periods. Simulation results with multivariate Gaussian and fat-tailed stochastic process calibrated to financial data show that both sampling frequencies and the presence of outliers cause instability in the inferred network. We conclude that instability of network properties do not necessarily indicate systemic instability.

Read the full article at: link.springer.com

No comment yet.
Suggested by Fil Menczer
Scoop.it!

Online misinformation is linked to early COVID-19 vaccination hesitancy and refusal

Online misinformation is linked to early COVID-19 vaccination hesitancy and refusal | Papers | Scoop.it

Francesco Pierri, Brea L. Perry, Matthew R. DeVerna, Kai-Cheng Yang, Alessandro Flammini, Filippo Menczer & John Bryden
Scientific Reports volume 12, Article number: 5966 (2022)

Widespread uptake of vaccines is necessary to achieve herd immunity. However, uptake rates have varied across U.S. states during the first six months of the COVID-19 vaccination program. Misbeliefs may play an important role in vaccine hesitancy, and there is a need to understand relationships between misinformation, beliefs, behaviors, and health outcomes. Here we investigate the extent to which COVID-19 vaccination rates and vaccine hesitancy are associated with levels of online misinformation about vaccines. We also look for evidence of directionality from online misinformation to vaccine hesitancy. We find a negative relationship between misinformation and vaccination uptake rates. Online misinformation is also correlated with vaccine hesitancy rates taken from survey data. Associations between vaccine outcomes and misinformation remain significant when accounting for political as well as demographic and socioeconomic factors. While vaccine hesitancy is strongly associated with Republican vote share, we observe that the effect of online misinformation on hesitancy is strongest across Democratic rather than Republican counties. Granger causality analysis shows evidence for a directional relationship from online misinformation to vaccine hesitancy. Our results support a need for interventions that address misbeliefs, allowing individuals to make better-informed health decisions.

Read the full article at: www.nature.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

The probabilistic pool punishment proportional to the difference of payoff outperforms previous pool and peer punishment

The probabilistic pool punishment proportional to the difference of payoff outperforms previous pool and peer punishment | Papers | Scoop.it

Tetsushi Ohdaira 
Scientific Reports volume 12, Article number: 6604 (2022

The public goods game is a multiplayer version of the prisoner’s dilemma game. In the public goods game, punishment on defectors is necessary to encourage cooperation. There are two types of punishment: peer punishment and pool punishment. Comparing pool punishment with peer punishment, pool punishment is disadvantageous in comparison with peer punishment because pool punishment incurs fixed costs especially if second-order free riders (those who invest in public goods but do not punish defectors) are not punished. In order to eliminate such a flaw of pool punishment, this study proposes the probabilistic pool punishment proportional to the difference of payoff. In the proposed pool punishment, each punisher pays the cost to the punishment pool with the probability proportional to the difference of payoff between his/her payoff and the average payoff of his/her opponents. Comparing the proposed pool punishment with previous pool and peer punishment, in pool punishment of previous studies, cooperators who do not punish defectors become dominant instead of pool punishers with fixed costs. However, in the proposed pool punishment, more punishers and less cooperators coexist, and such state is more robust against the invasion of defectors due to mutation than those of previous pool and peer punishment. The average payoff is also comparable to peer punishment of previous studies.

Read the full article at: www.nature.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Quantifying changes in societal optimism from online sentiment

Quantifying changes in societal optimism from online sentiment | Papers | Scoop.it

Calvin Isch, Marijn ten Thij, Peter M. Todd & Johan Bollen
Behavior Research Methods (2022)

Individuals can hold contrasting views about distinct times: for example, dread over tomorrow’s appointment and excitement about next summer’s vacation. Yet, psychological measures of optimism often assess only one time point or ask participants to generalize about their future. Here, we address these limitations by developing the optimism curve, a measure of societal optimism that compares positivity toward different future times that was inspired by the Treasury bond yield curve. By performing sentiment analysis on over 3.5 million tweets that reference 23 future time points (2 days to 30 years), we measured how positivity differs across short-, medium-, and longer-term future references. We found a consistent negative association between positivity and the distance into the future referenced: From August 2017 to February 2020, the long-term future was discussed less positively than the short-term future. During the COVID-19 pandemic, this relationship inverted, indicating declining near-future- but stable distant-future-optimism. Our results demonstrate that individuals hold differentiated attitudes toward the near and distant future that shift in aggregate over time in response to external events. The optimism curve uniquely captures these shifting attitudes and may serve as a useful tool that can expand existing psychometric measures of optimism.

Read the full article at: link.springer.com

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Scaling Beyond Cities

Scaling Beyond Cities | Papers | Scoop.it

Rafael Prieto Curiel, Carmen Cabrera-Arnau, Steven Richard Bishop

Front. Phys.

City population size is a crucial measure when trying to understand urban life. Many socio-economic indicators scale superlinearly with city size, whilst some infrastructure indicators scale sublinearly with city size. However, the impact of size also extends beyond the city’s limits. Here, we analyse the scaling behaviour of cities beyond their boundaries by considering the emergence and growth of nearby cities. Based on an urban network from African continental cities, we construct an algorithm to create the region of influence of cities. The number of cities and the population within a region of influence are then analysed in the context of urban scaling. Our results are compared against a random permutation of the network, showing that the observed scaling power of cities to enhance the emergence and growth of cities is not the result of randomness. By altering the radius of influence of cities, we observe three regimes. Large cities tend to be surrounded by many small towns for small distances. For medium distances (above 114 km), large cities are surrounded by many other cities containing large populations. Large cities boost urban emergence and growth (even more than 190 km away), but their scaling power decays with distance.

Read the full article at: www.frontiersin.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Funding CRISPR: Understanding the role of government and philanthropic institutions in supporting academic research within the CRISPR innovation system

David Fajardo-Ortiz, Stefan Hornbostel, Maywa Montenegro de Wit, Annie Shattuck
Quantitative Science Studies 1–21.

CRISPR/Cas has the potential to revolutionize medicine, agriculture, and biology. Understanding the trajectory of CRISPR research, how it is influenced and who pays for it, is an essential research policy question. We use a combination of methods to map, via quantitative content analysis of CRISPR papers, the research funding profile of major government agencies and organizations philanthropic, and the networks involved in supporting key stages of high-influence research, namely basic biological research and technological development. The results of the content analysis show how the research supported by the main US government agencies focus both on the study of CRISPR as a biological phenomenon and on its technological development and use as a biomedical research tool. US philanthropic organizations with the exception of HHMI, tend, by contrast, to specialize in funding CRISPR as a genome editing technology. We present a model of co-funding networks at the two most prominent institutions for CRISPR/Cas research, the University of California and the Harvard/MIT/Broad Institute, to illuminate how philanthropic organizations have articulated with government agencies to co-finance the discovery and development of CRISPR/Cas. Our results raise fundamental questions about the role of the state and the influence of philanthropy over the trajectory of transformative technologies.

Read the full article at: direct.mit.edu

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Emergence of Autocatalytic Sets in a Simple Model of Technological Evolution

Wim Hordijk, Stuart Kauffman
Two alternative views of an economy are combined and studied. The first view is that of technological evolution as a process of combinatorial innovation. Recently a simple mathematical model (TAP) was introduced to study such a combinatorial process. The second view is that of a network of production functions forming an autocatalytic set. Autocatalytic (RAF) sets have been studied extensively in the context of chemical reaction networks.
Here, we combine the two models (TAP and RAF) and show that they are compatible. In particular, it is shown that production function networks resulting from the combinatorial TAP model have a high probability of containing autocatalytic (RAF) sets. We also study the size distribution and robustness of such "economic autocatalytic sets", and compare our results with those from the chemical context. These initial results strongly support earlier claims that the economy can indeed be seen as an autocatalytic set.

Read the full article at: arxiv.org

No comment yet.
Scooped by Complexity Digest
Scoop.it!

Self-Organization in Network Sociotechnical Systems

Self-Organization in Network Sociotechnical Systems | Papers | Scoop.it

Svetlana Maltseva, Vasily Kornilov, Vladimir Barakhnin, and Alexander Gorbunov

Complexity Volume 2022 |Article ID 5714395

We can observe self-organization properties in various systems. However, modern networked dynamical sociotechnical systems have some features that allow for realizing the benefits of self-organization in a wide range of systems in economic and social areas. The review examines the general principles of self-organized systems, as well as the features of the implementation of self-organization in sociotechnical systems. We also delve into the production systems, in which the technical component is decisive, and social networks, in which the social component dominates; we analyze models used for modeling self-organizing networked dynamical systems. It is shown that discrete models prevail at the micro level. Furthermore, the review deals with the features of using continuous models for modeling at the macro level.

Read the full article at: www.hindawi.com

No comment yet.