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Introduction to QuantLib Development - Intensive 3-day Training Course - September 10-12th, 2018 - Download Registration Form Here


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Complexity Digest wrote a new blog post titled Cognitive mechanisms for human flocking dynamics
Low-level “adaptive” and higher-level “sophisticated” human reasoning processes have been proposed to play opposing roles in the emergence of unpredictable collective behaviors such as crowd panics, traffic jams, and market bubbles. While adaptive processes are widely recognized drivers of emergent social complexity, complementary theories of sophistication predict that incentives, education, and other inducements to rationality will suppress it. We show in a series of multiplayer laboratory experiments that, rather than suppressing complex social dynamics, sophisticated reasoning processes...
21 hours ago
Complexity Digest wrote a new blog post titled Zipf’s and Taylor’s laws
Zipf’s law states that the frequency of an observation with a given value is inversely proportional to the square of that value; Taylor’s law, instead, describes the scaling between fluctuations in the size of a population and its mean. Empirical evidence of the validity of these laws has been found in many and diverse domains. Despite the numerous models proposed to explain the presence of Zipf’s law, there is no consensus on how it originates from a microscopic process of individual dynamics without fine-tuning. Here we show that Zipf’s law and Taylor’s law can...
3 days ago
Complexity Digest wrote a new blog post titled Two postdoctoral positions in computational social science at the Network Science Institute
Two postdoctoral positions in computational social science are available at the Network Science Institute, to work with David Lazer and Christoph Riedl. Candidates will be expected to work on a combination of their own research and collaborative projects within the institute. Source: christophriedl.net
3 days ago
Complexity Digest wrote a new blog post titled Measuring accessibility using gravity and radiation models
Since the presentation of the radiation model, much work has been done to compare its findings with those obtained from gravitational models. These comparisons always aim at measuring the accuracy with which the models reproduce the mobility described by origin–destination matrices. This has been done at different spatial scales using different datasets, and several versions of the models have been proposed to adjust to various spatial systems. However, the models, to our knowledge, have never been compared with respect to policy testing scenarios. For this reason, here we use the models to...
5 days ago
Complexity Digest wrote a new blog post titled Criticality distinguishes the ensemble of biological regulatory networks
The hypothesis many living systems should exhibit near-critical behavior is well-motivated theoretically, and an increasing number of cases have been demonstrated empirically. However, a systematic analysis across biological networks, which would enable identification of the network properties that drive criticality, has not yet been realized. Here, we provide a first comprehensive survey of criticality across a diverse sample of biological networks, leveraging a publicly available database of 67 Boolean models of regulatory circuits. We find all 67 networks to be near-critical. By comparing...
6 days ago
Complexity Digest wrote a new blog post titled Physical foundations of biological complexity
Living organisms are characterized by a degree of hierarchical complexity that appears to be inaccessible to even the most complex inanimate objects. Routes and patterns of the evolution of complexity are poorly understood. We propose a general conceptual framework for emergence of complexity through competing interactions and frustrated states similar to those that yield patterns in striped glasses and cause self-organized criticality. We show that biological evolution is replete with competing interactions and frustration that, in particular, drive major transitions in evolution. The key...
6 days ago
Complexity Digest wrote a new blog post titled Gaia 2.0
According to Lovelock and Margulis’s Gaia hypothesis, living things are part of a planetary-scale self-regulating system that has maintained habitable conditions for the past 3.5 billion years (1, 2). Gaia has operated without foresight or planning on the part of organisms, but the evolution of humans and their technology are changing that. Earth has now entered a new epoch called the Anthropocene (3), and humans are beginning to become aware of the global consequences of their actions. As a result, deliberate self-regulation—from personal action to global geoengineering schemes—is...
8 days ago
Complexity Digest wrote a new blog post titled Closed Loophole Confirms the Unreality of the Quantum World
After researchers found a loophole in a famous experiment designed to prove that quantum objects don’t have intrinsic properties, three experimental groups quickly sewed the loophole shut. The episode closes the door on many “hidden variable” theories. Source: www.quantamagazine.org
9 days ago
Complexity Digest wrote a new blog post titled What has and hasn’t changed since the global financial crisis?
The world economy has returned to robust growth after the 2008 global financial crisis. But some familiar risks are creeping back, and new ones have emerged. Source: www.mckinsey.com
10 days ago
Complexity Digest wrote a new blog post titled Physics of humans, physics for society
Today, the massive use of information and communication technologies (ICT) has made it possible to attach a traceable set of data to almost any person. We argue that these data provide the opportunity to build a ‘physics of society’: describing a society — composed of many interacting heterogeneous entities (people, businesses, institutions) — as a physical system. While important ethical implications have to be taken into account, the benefits in developing such physics of society would be tremendous. Indeed, it could help understanding, anticipating and forecasting future societal trends...
10 days ago
Complexity Digest wrote a new blog post titled Comparing two classes of biological distribution systems using network analysis
Distribution networks such as vasculature systems or urban transportation pathways are prevalent in our world. Understanding how different kinds of transport systems are organized to allow for efficient function in their environments and in the presence of constraints on material costs is currently an open area of investigation. In this study, we use methods from network science to compare and contrast the structure of two different classes of biological distribution networks: mycelial fungi and rodent brain vasculature. While each of these systems have been studied separately, less work has...
11 days ago
Complexity Digest wrote a new blog post titled Attack Tolerance of Link Prediction Algorithms: How to Hide Your Relations in a Social Network
Link prediction is one of the fundamental research problems in network analysis. Intuitively, it involves identifying the edges that are most likely to be added to a given network, or the edges that appear to be missing from the network when in fact they are present. Various algorithms have been proposed to solve this problem over the past decades. For all their benefits, such algorithms raise serious privacy concerns, as they could be used to expose a connection between two individuals who wish to keep their relationship private. With this in mind, we investigate the ability of such...
12 days ago
Complexity Digest wrote a new blog post titled Emergent rules of computation in the Universe lead to life and consciousness: a computational framework for consciousness
We introduce a computational framework for consciousness. We hypothesize that emergent rules of computation in the Universe lead to life and consciousness. We live in a Universe that has a substrate capable of computing or information processing. We suggest that in principle, any Universe that is capable of supporting information processing and has energy can evolve life and consciousness. We hypothesize that the Universe encodes rules in the form of physical laws that allow for the emergence of both life and conscious organisms. A key insight is that there are different levels of...
12 days ago
Complexity Digest wrote a new blog post titled Assistant Professor (Tenure Track), Communication Theory employing Computational Methods, UC Davis
We seek a colleague whose primary research interests are concerned with explicating, understanding, and evaluating fundamental processes of communication. The candidate must satisfy two criteria. First, candidates must have a track record of communication research that is theoretically innovative. Specifically, the successful candidate is expected to have a research program that advances at least one key area of communication, such as neuroscience, virtual reality, serious games, persuasion, media processes and effects, computer-mediated communication, political communication, social...
13 days ago
Complexity Digest wrote a new blog post titled Freedom: The Holberg Lecture, 2018 by Cass R. Sunstein
If people have freedom of choice, do their lives go better? Under what conditions? By what criteria? Consider three distinct problems. (1) In countless situations, human beings face a serious problem of “navigability”; they do not know how to get to their preferred destination, whether the issue involves health, education, employment, or well-being in general. This problem is especially challenging for people who live under conditions of severe deprivation, but it can be significant for all of us. (2) Many of us face problems of self-control, and our decisions today endanger our own future....
13 days ago
Complexity Digest wrote a new blog post titled Centrality-Friendship Paradoxes: When Our Friends Are More Important Than Us
The friendship paradox states that, on average, our friends have more friends than we do. In network terms, the average degree over the nodes can never exceed the average degree over the neighbours of nodes. This effect, which is a classic example of sampling bias, has attracted much attention in the social science and network science literature, with variations and extensions of the paradox being defined, tested and interpreted. Here, we show that a version of the paradox holds rigorously for eigenvector centrality: on average, our friends are more important than us. We then consider general...
15 days ago
Complexity Digest wrote a new blog post titled Optimization of privacy-utility trade-offs under informational self-determination
•A generic and novel computational framework is introduced for measuring and optimizing privacy-utility trade-offs. •The framework applicability is validated analytically and empirically using real-world data from a Smart Grid pilot project. •Privacy-utility trade-offs are optimized under informational self determination.   Optimization of privacy-utility trade-offs under informational self-determinationThomas Asikis, Evangelos Pournaras Future Generation Computer Systems Source: www.sciencedirect.com
16 days ago
Complexity Digest wrote a new blog post titled Social interactions shape individual and collective personality in social spiders
The behavioural composition of a group and the dynamics of social interactions can both influence how social animals work collectively. For example, individuals exhibiting certain behavioural tendencies may have a disproportionately large impact on the group, and so are referred to as keystone individuals, while interactions between individuals can facilitate information transmission about resources. Despite the potential impact of both behavioural composition and interactions on collective behaviour, the relationship between consistent behaviours (also known as personalities) and social...
18 days ago
Complexity Digest wrote a new blog post titled Swarm Robotics – Pushing the state of the art
Swarm robotics is the domain of robotics that deals with large groups of robots that coordinately and cooperatively accomplish a task. Inspired by natural self-organising systems like ant colonies, fish schools or bird flocks, the goal of swarm robotics research is to deploy complex robotics systems that present robustness to faults, scalability to different group sizes, flexibility of the displayed behaviour and adaptivity to environmental changes.The problems faced by swarm robotics concerns mainly the analysis of complex systems formed by a multitude of interacting units, the design of...
19 days ago
Complexity Digest wrote a new blog post titled Entropy | Special Issue : Information Theory in Complex Systems
Complex systems are ubiquitous in the natural and engineered worlds. Examples are self-assembling materials, the Earth’s climate, single- and multi-cellular organisms, the brain, and coupled socio-economic and socio-technical systems, to mention a few canonical examples. The use of Shannon information theory to study the behavior of such systems, and to explain and predict their dynamics, has gained significant attention, both from a theoretical and from an experimental viewpoint. There have been many advances in applying Shannon theory to complex systems, including correlation analyses...
20 days ago