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Complexity Digest wrote a new blog post titled Localist plasticity identified by mutual information
The issue of memory is difficult for standard neural network models. Ubiquitous synaptic plasticity introduces the problem of interference, which limits pattern recall and introduces conflation errors. We present a lognormal recurrent neural network, load patterns into it (MNIST), and test the resulting neural representation for information content by an output classifier. We identify neurons, which ‘compress’ the pattern information into their own adjacency network, and by stimulating these achieve recall. Learning is limited to intrinsic plasticity and output synapses of these pattern...
2 days ago
Complexity Digest wrote a new blog post titled Exploration of the chemical space and its three historical regimes
We found that the number of new chemical compounds has grown exponentially with a 4.4% annual production rate from 1800 to 2015 not even affected by World Wars. There are three distinct growth regimes: proto-organic, organic, and organometallic, with decreasing variability in the production of compounds over time. Contrary to the belief that organic synthesis developed only after 1828, synthesis had been a key provider of new compounds already at the beginning of the 19th century. By 1900, it became the established tool to report new compounds. We found that chemists are conservative when...
5 days ago
Complexity Digest wrote a new blog post titled Quantifying the sensing power of vehicle fleets
Attaching sensors to crowd-sourced vehicles could provide a cheap and accurate way to monitor air pollution, road quality, and other aspects of a city’s health. But in order for so-called drive-by sensing to be practically useful, the sensor-equipped vehicle fleet needs to have large “sensing power”—that is, it needs to cover a large fraction of a city’s area during a given reference period. Here, we provide an analytic description of the sensing power of taxi fleets, which agrees with empirical data from nine major cities. Our results show taxis’ sensing power is unexpectedly large—in...
6 days ago
Complexity Digest wrote a new blog post titled Postgraduate School of Thinking, Vrije Universiteit Brussel
At the most fundamental level many of the problems we face are the unfortunate outcome of the malpractice of thinking. Whichever complex problem one may consider –be it ecological, societal, political, economic, organisational etc.– one will likely find that it is caused by the clashing of incompatible or inadequate manners of thinking. Even when these are genuinely well intended and strongly self-justified, they often inadvertently contribute to composite problematics.The inadequacies of our thinking are deeply entrenched in the way that we humans, perceive the world, ourselves in the world,...
6 days ago
Complexity Digest wrote a new blog post titled Advances in Complex Systems and Their Applications to Cybersecurity
Cybersecurity is one of the fastest growing and largest technology sectors and is increasingly being recognized as one of the major issues in many industries, so companies are increasing their security budgets in order to guarantee the security of their processes. Successful menaces to the security of information systems could lead to safety, environmental, production, and quality problems. One of the most harmful issues of attacks and intrusions is the ever-changing nature of attack technologies and strategies, which increases the difficulty of protecting computer systems. As a result,...
7 days ago
Complexity Digest wrote a new blog post titled Call for Applications: Cátedra Germinal Cocho en Ciencias de la Complejidad (Senior posdoc)
The Center for Complexity Sciences (C3) at the Universidad Nacional Autónoma de México is seeking candidates for a one year researcher position (extensible for a second year).   The candidates should have more than ten publications in indexed journals and to have directed at least one thesis (doctorate, masters, or bachelors). Projects can be individual or related to current research at the C3. Source: complexes.blogspot.com
7 days ago
Complexity Digest wrote a new blog post titled Complex Methods Applied to Data Analysis, Processing, and Visualisation
The amount of data available every day is not only enormous but growing at an exponential rate. Over the last ten years there has been an increasing interest in using complex methods to analyse and visualise massive datasets, gathered from very different sources and including many different features: social networks, surveillance systems, smart cities, medical diagnosis systems, business information, cyberphysical systems, and digital media data. Nowadays, there are a large number of researchers working in complex methods to process, analyse, and visualise all this information, which can be...
8 days ago
Complexity Digest wrote a new blog post titled Complexity in Forecasting and Predictive Models
The challenge of this special issue has been to know the state of the problem related to forecasting modeling and the creation of a model to forecast the future behavior that supports decision making by supporting real-world applications. This issue has been highlighted by the quality of its research work on the critical importance of advanced analytical methods, such as neural networks, soft computing, evolutionary algorithms, chaotic models, cellular automata, agent-based models, and finite mixture minimum squares (FIMIX-PLS) Mainly, all the papers are focused on triggering a substantive...
9 days ago
Complexity Digest wrote a new blog post titled On complexity of branching droplets in electrical field
Decanol droplets in a thin layer of sodium decanoate with sodium chloride exhibit bifurcation branching growth due to interplay between osmotic pressure, diffusion and surface tension. We aimed to evaluate if morphology of the branching droplets changes when the droplets are subject to electrical potential difference. We analysed graph-theoretic structure of the droplets and applied several complexity measures. We found that, in overall, the current increases complexity of the branching droplets in terms of number of connected components and nodes in their graph presentations, morphological...
9 days ago
Complexity Digest wrote a new blog post titled Machine Learning and Modeling at CSS’2019
The science of complex systems provides the framework for understanding patterns of behavior, and their emergence, at multiple scales in social and other types of systems. The analytical toolsets provided by AI and Machine Learning are good to recognize and measure such patterns in the data. The combination of pattern recognition and generation mechanisms provides an opportunity to advance our understanding of the complexity of real systems. Ultimately, we could benefit from such complexity, rather than being endangered by it, design better technologies, decisions and strategies. Show new...
10 days ago
Complexity Digest wrote a new blog post titled A simple contagion process describes spreading of traffic jams in urban networks
The spread of traffic jams in urban networks has long been viewed as a complex spatio-temporal phenomenon that often requires computationally intensive microscopic models for analysis purposes. In this study, we present a framework to describe the dynamics of congestion propagation and dissipation of traffic in cities using a simple contagion process, inspired by those used to model infectious disease spread in a population. We introduce two novel macroscopic characteristics of network traffic, namely congestion propagation rate \b{eta} and congestion dissipation rate {\mu}. We describe the...
10 days ago
Complexity Digest wrote a new blog post titled Gender-specific preference in online dating
In this paper, to reveal the differences of gender-specific preference and the factors affecting potential mate choice in online dating, we analyze the users’ behavioral data of a large online dating site in China. We find that for women, network measures of popularity and activity of the men they contact are significantly positively associated with their messaging behaviors, while for men only the network measures of popularity of the women they contact are significantly positively associated with their messaging behaviors. Secondly, when women send messages to men, they pay attention to not...
10 days ago
Complexity Digest wrote a new blog post titled Human information processing in complex networks
Humans communicate using systems of interconnected stimuli or concepts — from language and music to literature and science — yet it remains unclear how, if at all, the structure of these networks supports the communication of information. Although information theory provides tools to quantify the information produced by a system, traditional metrics do not account for the inefficient and biased ways that humans process this information. Here we develop an analytical framework to study the information generated by a system as perceived by a human observer. We demonstrate...
11 days ago
Complexity Digest wrote a new blog post titled Interacting contagions are indistinguishable from social reinforcement
From fake news to innovative technologies, many contagions spread via a process of social reinforcement, where multiple exposures are distinct from prolonged exposure to a single source. Contrarily, biological agents such as Ebola or measles are typically thought to spread as simple contagions. Here, we demonstrate that interacting simple contagions are indistinguishable from complex contagions. In the social context, our results highlight the challenge of identifying and quantifying mechanisms, such as social reinforcement, in a world where an innumerable amount of ideas, memes and behaviors...
12 days ago
Complexity Digest wrote a new blog post titled Simplicial models of social contagion
Complex networks have been successfully used to describe the spread of diseases in populations of interacting individuals. Conversely, pairwise interactions are often not enough to characterize social contagion processes such as opinion formation or the adoption of novelties, where complex mechanisms of influence and reinforcement are at work. Here we introduce a higher-order model of social contagion in which a social system is represented by a simplicial complex and contagion can occur through interactions in groups of different sizes. Numerical simulations of the model on both empirical...
13 days ago
Complexity Digest wrote a new blog post titled Proceedings A Special Feature: A Generation of Network Science. Call for papers
On the eve of 20th century, three papers launched the modern Network Science by bringing it to the attention of a wider community of physicists, computer scientists and applied mathematicians. The papers – by Watts and Strogatz [1], Barabasi and Albert [2], and Google founders Brin and Page [3] – introduced “small world networks”, “preferential attachment,” and “PageRank” into the vernacular of network scientists. They showed that simple models could reproduce much of the complexity observed in network structure and that the structure of networks was linked to their function. As...
13 days ago
Complexity Digest wrote a new blog post titled An Overview of Open-Ended Evolution: Editorial Introduction to the Open-Ended Evolution II Special Issue
Nature’s spectacular inventiveness, reflected in the enormous diversity of form and function displayed by the biosphere, is a feature of life that distinguishes living most strongly from nonliving. It is, therefore, not surprising that this aspect of life should become a central focus of artificial life. We have known since Darwin that the diversity is produced dynamically, through the process of evolution; this has led life’s creative productivity to be called Open-Ended Evolution (OEE) in the field. This article introduces the second of two special issues on current research in...
16 days ago
Complexity Digest wrote a new blog post titled Worlds Hidden in Plain Sight
Over the last three decades, the Santa Fe Institute and its network of researchers have been pursuing a revolution in science. Ignoring the boundaries of disciplines and schools and searching for novel fundamental ideas, theories, and practices, this international community integrates the full range of scientific inquiries that will help us to understand and survive on a complex planet. This volume collects essays from the past thirty years of research, in which contributors explain in clear and accessible language many of the deepest challenges and insights of complexity science. Explore the...
18 days ago
Complexity Digest wrote a new blog post titled What is the Entropy of a Social Organization?
We quantify a social organization’s potentiality, that is its ability to attain different configurations. The organization is represented as a network in which nodes correspond to individuals and (multi-)edges to their multiple interactions. Attainable configurations are treated as realizations from a network ensemble. To encode interaction preferences between individuals, we choose the generalized hypergeometric ensemble of random graphs, which is described by a closed-form probability distribution. From this distribution we calculate Shannon entropy as a measure of potentiality. This...
19 days ago
Complexity Digest wrote a new blog post titled Ancient DNA Yields Clues to Past Biodiversity
Surviving fragments of genetic material preserved in sediments allow metagenomics researchers to see the full diversity of past life — even microbes. Source: www.quantamagazine.org
20 days ago