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Relative importance of social synergy, assortation and networks in the evolution of social cooperation

We compare the likelihood of different socially relevant features to allow the evolutionary emergence and maintenance of cooperation in a generalized variant of the iterated Prisoners Dilemma game. Results show that the average costs/benefit balance of cooperation is the primary constraint for its establishment and maintenance. Behavior increasing inclusive fitness such as assortation, homophily, kin-selection and tagging of individuals, is second in importance. Networks characteristics were the least important in favoring the establishment and maintenance of cooperation, despite being the most popular in recent research on the subject. Results suggest that inclusive fitness theory with its expansions to include assortative and economic considerations is more general, powerful and relevant in analyzing social phenomena than kin selection theory with its emphasis on genetic relatedness. Merging economics with evolutionary theory will be necessary to reveal more about the nature of social dynamics.

 

Relative importance of social synergy, assortation and networks in the evolution of social cooperation
Claudia Montoreano, Klaus Jaffe

http://arxiv.org/abs/1311.4407

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Computation, Cognition and Constructivism: Introduction to the Special Issue

Computation, Cognition and Constructivism: Introduction to the Special Issue | Papers | Scoop.it

Context: Most constructivist discourse is situated at the philosophical-conceptual level, where arguments appeal to the intuition of the reader, while formal-computational models have only been taken into account to a very limited degree so far. Problem: Two types of problems need to be addressed: Synthetically, can constructivist concepts be turned into actual computational implementations? Can these be further conceptual developments in constructivist theory as such, or are they just an application thereof? Conceptually, does the notion of computation square with constructivist approaches at all? Method: Paradigmatically, we discuss the meaning of “computational” in cognitive agents that comply with constructivist concepts. Also, we summarize the contributions. Results: From a constructivist point of view, the concept of “computational model” is ambiguous and depends on whether it is used in the sense of the computational(ist) theory of mind or simply as a tool. Implications: The insights presented in the contributions to this special issue point in the direction of a computational extension of constructivist approaches as well as a constructivist extension to computational approaches. However, while many of the questions we posed were discussed in the contributions and open peer commentaries, some of them were largely neglected and thus are subject to further discussion.
Key words: Artificial intelligence, artificial life, cognitive sciences, computation, computational theory of mind, constructivism, models

 

Riegler A., Stewart J. & Ziemke T. (2013) Computation, Cognition and Constructivism: Introduction to the Special Issue. Constructivist Foundations 9(1): 1–6. Available at http://www.univie.ac.at/constructivism/journal/9/1/001.riegler

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Multidisciplinary applications of complex networks modeling, simulation, visualization, and analysis

(...) complex systems are characterized by the interactions between their numerous elements. The word ‘complex’ comes from the Latin plexus which means entwined. In other words, it is difficult to correlate global properties of complex systems with the properties of the individual constituent components. This is primarily because the interactions between these individual elements partly determine the future states of the system (Gershenson 2013). If these interactions are not included in the developed models, the models would not be an accurate reflection of the modelled phenomenon.

 

Gershenson, C. & M. A. Niazi (2013). Multidisciplinary applications of complex networks modeling, simulation, visualization, and analysis. Complex Adaptive Systems Modeling 1:17  http://dx.doi.org/10.1186/2194-3206-1-17

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The Math of Segregation » American Scientist

The Math of Segregation » American Scientist | Papers | Scoop.it

In the 1960s Schelling devised a simple model in which a mixed group of people spontaneously segregates by race even though no one in the population desires that outcome. Initially, black and white families are randomly distributed. At each step in the modeling process the families examine their immediate neighborhood and either stay put or move elsewhere depending on whether the local racial composition suits their preferences. The procedure is repeated until everyone finds a satisfactory home (or until the simulator’s patience is exhausted).


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Country- and age-specific optimal allocation of dengue vaccines

We developed a model of dengue transmission that incorporates the age-specific distributions of dengue burden corresponding to those in Thailand and Brazil ... taking into account limited availability of vaccine doses in the initial phase of production. [...] More specifically, we showed that, during the first years following introduction of a dengue vaccine, it is optimal to target children for dengue mass vaccination in Thailand, whereas young adults should be targeted in Brazil.

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The Trojan female technique: a novel, effective and humane approach for pest population control

Humankind's ongoing battle with pest species spans millennia. [...] One of the most successful such ‘fertility control’ strategies developed to date is the sterile male technique (SMT), in which large numbers of sterile males are released into a population each generation. [...] We use mathematical models to test a new twist on the SMT, using maternally inherited mitochondrial (mtDNA) mutations that affect male, but not female reproductive fitness. ‘Trojan females’ carrying such mutations, and their female descendants, produce ‘sterile-male’-equivalents under natural conditions over multiple generations.

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Geo-located Twitter as the proxy for global mobility patterns

In the advent of a pervasive presence of location sharing services researchers gained an unprecedented access to the direct records of human activity in space and time. This paper analyses geo-located Twitter messages in order to uncover global patterns of human mobility. Based on a dataset of almost a billion tweets recorded in 2012 we estimate volumes of international travelers in respect to their country of residence. We examine mobility profiles of different nations looking at the characteristics such as mobility rate, radius of gyration, diversity of destinations and a balance of the inflows and outflows. The temporal patterns disclose the universal seasons of increased international mobility and the peculiar national nature of overseen travels. Our analysis of the community structure of the Twitter mobility network, obtained with the iterative network partitioning, reveals spatially cohesive regions that follow the regional division of the world. Finally, we validate our result with the global tourism statistics and mobility models provided by other authors, and argue that Twitter is a viable source to understand and quantify global mobility patterns.

 

Geo-located Twitter as the proxy for global mobility patterns
Bartosz Hawelka, Izabela Sitko, Euro Beinat, Stanislav Sobolevsky, Pavlos Kazakopoulos, Carlo Ratti

http://arxiv.org/abs/1311.0680

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Zipf's law unzipped

Introduction and background. The outcome of a random process is often well described by a bell-shaped curve, the normal distribution. Some hundred years ago, it was noticed that things like the richness among people, town sizes, surnames, and the frequency of words have different, broader distributions. The figure shows the probability of finding a word which occurs k times in a novel. If the words were distributed according to normal expectations, they would fall on the full curve in the figure. Many, more or less system-specific, proposals for the deviation from normal have been suggested under names such as 'rich gets richer', 'principle of least effort', 'preferential attachment' and 'independent proportional growth'. Here, it is argued that the phenomenon is connected to a more ubiquitous random group formation. A group is like a soccer team with positions to fill. You want the right player in the right position. Thus, unlike the normal distribution where you pick a player for the team, one now tries to pick a player for a position in the team.
Main results. Information theory is used to find the most likely distribution of group sizes given the number of objects, groups and the number of objects in the largest group. The result is the dashed curve in the figure. The same striking agreement is found for all data sets investigated.
Wider implications. This paper gives a new starting point for the understanding of Zipf-type phenomena.

 

Zipf's law unzipped

Seung Ki Baek et al 2011 New J. Phys. 13 043004 http://dx.doi.org/10.1088/1367-2630/13/4/043004

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Romantic Partnerships and the Dispersion of Social Ties: A Network Analysis of Relationship Status on Facebook

A crucial task in the analysis of on-line social-networking systems is to identify important people --- those linked by strong social ties --- within an individual's network neighborhood. Here we investigate this question for a particular category of strong ties, those involving spouses or romantic partners. We organize our analysis around a basic question: given all the connections among a person's friends, can you recognize his or her romantic partner from the network structure alone? Using data from a large sample of Facebook users, we find that this task can be accomplished with high accuracy, but doing so requires the development of a new measure of tie strength that we term `dispersion' --- the extent to which two people's mutual friends are not themselves well-connected. The results offer methods for identifying types of structurally significant people in on-line applications, and suggest a potential expansion of existing theories of tie strength.

 

Romantic Partnerships and the Dispersion of Social Ties: A Network Analysis of Relationship Status on Facebook
Lars Backstrom, Jon Kleinberg

http://arxiv.org/abs/1310.6753

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A Big Data Approach to Computational Creativity

Computational creativity is an emerging branch of artificial intelligence that places computers in the center of the creative process. Broadly, creativity involves a generative step to produce many ideas and a selective step to determine the ones that are the best. Many previous attempts at computational creativity, however, have not been able to achieve a valid selective step. This work shows how bringing data sources from the creative domain and from hedonic psychophysics together with big data analytics techniques can overcome this shortcoming to yield a system that can produce novel and high-quality creative artifacts. Our data-driven approach is demonstrated through a computational creativity system for culinary recipes and menus we developed and deployed, which can operate either autonomously or semi-autonomously with human interaction. We also comment on the volume, velocity, variety, and veracity of data in computational creativity.

 

A Big Data Approach to Computational Creativity
Lav R. Varshney, Florian Pinel, Kush R. Varshney, Debarun Bhattacharjya, Angela Schoergendorfer, Yi-Min Chee

http://arxiv.org/abs/1311.1213

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Can you spot a WIMP?

So with the Higgs particle sighted and the gongs distributed, physics seems finally ready to move on. Unless the Higgs had remained elusive, or had turned out to have much more mass than theories predicted, it was always going to be the end of a story: the final piece of a puzzle assembled over the past several decades. But now the hope is that the Large Hadron Collider, and several other big machines and experiments worldwide, will be able to open a new book, containing physics that we don’t yet understand at all. And the first chapter seems likely to be all about dark matter.

 

http://www.prospectmagazine.co.uk/ball/can-you-spot-a-wimp

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Connection, Connection, Connection…

There are approximately 86 billion neurons in the human brain. Over the past decades, we have made enormous progress in understanding their molecular, genetic, and structural makeup as well as their function. However, the real power of the central nervous system lies in the smooth coordination of large numbers of neurons. Neurons are thus organized on many different scales, from small microcircuits and assemblies all the way to regional brain networks. To interact effectively on all these levels, neurons, nuclei, cortical columns, and larger areas need to be connected. The study of neuronal connectivity has expanded rapidly in past years. Large research groups have recently joined forces and formed consortia to tackle the difficult problems of how to experimentally investigate connections in the brain and how to analyze and make sense of the enormous amount of data that arises in the process.
This year's neuroscience special issue is devoted to general and also several more specific aspects of research on connectivity in the brain. We invited researchers to review the most recent progress in their fields and to provide us with an outlook on what the future may hold in store.

 

Connection, Connection, Connection…
Peter Stern

Science 1 November 2013:
Vol. 342 no. 6158 p. 577
http://dx.doi.org/10.1126/science.342.6158.577

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PLOS Biology: Collection Overview: Ten Years of Wonderful Open Access Science

PLOS Biology: Collection Overview: Ten Years of Wonderful Open Access Science | Papers | Scoop.it

To mark our tenth Anniversary at PLOS Biology, we are launching a special, celebratory Tenth Anniversary PLOS Biology Collection which showcases 10 specially selected PLOS Biology research articles drawn from a decade of publishing excellent science. It also features newly commissioned articles, including thought-provoking pieces on the Open Access movement (past and present), on article-level metrics, and on the history of the Public Library of Science. Each research article highlighted in the collection is also accompanied by a PLOS Biologue blog post to extend the impact of these remarkable studies to the widest possible audience.

 

Roberts RG, Alfred J (2013) Collection Overview: Ten Years of Wonderful Open Access Science. PLoS Biol 11(10): e1001688. http://dx.doi.org/10.1371/journal.pbio.1001688

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A Comparison of Tram Priority at Signalized Intersections

We study tram priority at signalized intersections using a stochastic cellular automaton model for multimodal traffic flow. We simulate realistic traffic signal systems, which include signal linking and adaptive cycle lengths and split plans, with different levels of tram priority. We find that tram priority can improve service performance in terms of both average travel time and travel time variability. We consider two main types of tram priority, which we refer to as full and partial priority. Full tram priority is able to guarantee service quality even when traffic is saturated, however, it results in significant costs to other road users. Partial tram priority significantly reduces tram delays while having limited impact on other traffic, and therefore achieves a better result in terms of the overall network performance. We also study variations in which the tram priority is only enforced when trams are running behind schedule, and we find that those variations retain almost all of the benefit for tram operations but with reduced negative impact on the network.

 

A Comparison of Tram Priority at Signalized Intersections
Lele Zhang, Timothy Garoni

http://arxiv.org/abs/1311.3590

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Evolution in a Finite World

Evolution in a Finite World | Papers | Scoop.it

Sex is ubiquitous. The vast majority of animals and plants reproduce sexually at least some of the time. Some, such as humans, can reproduce no other way. Figuring out why sex is so common, though, has been a longstanding challenge for evolutionary biologists.
The problem is that, as a reproductive strategy, sex seems wasteful. The mere fact that you have survived to adulthood means that you are reasonably well adapted to your environment, and it is not at all clear that reshuffling your genes with those of someone else will lead to anything as good, let alone better. Furthermore, a female who reproduces asexually by making diploid eggs passes roughly twice as much of her genetic material on to the next generation as does one who reproduces sexually. Overall, cloning yourself would seem to be the way to go.

 

http://nautil.us/issue/7/waste/evolution-in-a-finite-world

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Designing complex dynamics in cellular automata with memory

Since their inception at Macy conferences in later 1940s, complex systems have remained the most controversial topic of interdisciplinary sciences. The term "complex system" is the most vague and liberally used scientific term. Using elementary cellular automata (ECA), and exploiting the CA classification, we demonstrate elusiveness of "complexity" by shifting space-time dynamics of the automata from simple to complex by enriching cells with memory. This way, we can transform any ECA class to another ECA class — without changing skeleton of cell-state transition function — and vice versa by just selecting a right kind of memory. A systematic analysis displays that memory helps "discover" hidden information and behavior on trivial — uniform, periodic, and nontrivial — chaotic, complex — dynamical systems.

 

Martinez, G. J., Adamatzky, A. and Alonso-Sanz, R. (2013) Designing complex dynamics in cellular automata with memory. International Journal of Bifurcation and Chaos, 23 (10). p. 1330035. ISSN 0218-1274

http://eprints.uwe.ac.uk/21980/

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Generating a Synthetic Population of Individuals in Households

This paper focuses on the problem of generating a virtual population with the best use of (aggregated and sample-population individual) data, especially when the goal is generating both individuals and their organisation in households.

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Cooperation promotes the evolution of separate sexes from hermaphrodites with unitary growth

Most animals have specialized into separate sexes but most plants remain hermaphroditic. The underlining cause for this is still unclear. Here we address this question by evolutionary stable strategy analysis and exact calculation of frequency-dependent selection and genetic drift in geographically structured populations.

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Quantum information and the problem of mechanisms of biological evolution

Here, a model of partially directed evolution, based on the learning automata theory, which includes a priori information about the fitness space, is proposed.

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Using Chaos Theory to Predict and Prevent Catastrophic 'Dragon King' Events

Using Chaos Theory to Predict and Prevent Catastrophic 'Dragon King' Events | Papers | Scoop.it

Stop a stock trade and avoid a catastrophic global financial crash. Seal a microscopic crack and prevent a rocket explosion. Push a button to avert a citywide blackout.

Though such situations are mostly fantasies, a new analysis suggests that certain types of extreme events occurring in complex systems – known as dragon king events – can be predicted and prevented.


Via Claudia Mihai
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Ali Anani's curator insight, November 9, 2013 3:54 AM

Can we control  the uncontrollable? 

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Matchmaker, matchmaker, make me a match: migration of populations via marriages in the past

The study of human mobility is both of fundamental importance and of great potential value. For example, it can be leveraged to facilitate efficient city planning and improve prevention strategies when faced with epidemics. The newfound wealth of rich sources of data---including banknote flows, mobile phone records, and transportation data---have led to an explosion of attempts to characterize modern human mobility. Unfortunately, the dearth of comparable historical data makes it much more difficult to study human mobility patterns from the past. In this paper, we present such an analysis: we demonstrate that the data record from Korean family books (called "jokbo") can be used to estimate migration patterns via marriages from the past 750 years. We apply two generative models of long-term human mobility to quantify the relevance of geographical information to human marriage records in the data. Using the different geographic distributions of clans, we quantify the "ergodicity" of clans in terms of how widely and uniformly they have spread across Korea, and we compare these results to those obtained using surname data from the Czech Republic. Based on the correlation between ergodicity and migration patterns in Korea, we identify two different types of migration patterns: diffusive and convective.

 

Matchmaker, matchmaker, make me a match: migration of populations via marriages in the past
Sang Hoon Lee, Robyn Ffrancon, Daniel M. Abrams, Beom Jun Kim, Mason A. Porter

http://arxiv.org/abs/1310.7532

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Is modern science evolving in the wrong direction?

The present politically correct consensus is that increased exchange of scientific insight, knowledge, practitioners and skills at the global level brings significant benefits to all. The quantifiable scientometric changes during the last decade, however, suggest that many areas of knowledge are evolving in the opposite direction. Despite an increase during the last decade of the numbers of journals and academic articles published, increases in the number of citations the published articles receive, and increases in the number of countries participating; important parts of the academic activity are becoming more nationalistic. In addition, international collaboration is decreasing in several subject areas, and in several geographic regions. For example, countries in Asia are becoming scientifically more isolated; and academics working in the humanities in all the regions of the world are very nationalistic and are becoming more so. The precise consequences of this dynamics are difficult to predict, but it certainly will have reverberations beyond academia. The tendency of the humanities to become more provincial will certainly not help in reducing international conflicts arising from poor understanding of cultural differences and of diverging sociopolitical world views. More and better data on these trends should give us a better understanding for eventually improving academic policies worldwide. 

 

Is modern science evolving in the wrong direction?
Klaus Jaffe

http://arxiv.org/abs/1311.1426

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Game theory in models of pedestrian room evacuation

We analyze the pedestrian evacuation of a rectangular room with a single door considering a Lattice Gas scheme with the addition of behavioral aspects of the pedestrians. The movement of the individuals is based on random and rational choices and is affected by conflicts between two or more agents that want to advance to the same position. Such conflicts are solved according to certain rules closely related to the concept of strategies in Game Theory, cooperation and defection. We consider game rules analogous to those from the Prisoner's Dilemma and Stag Hunt games, with payoffs associated to the probabilities of the individuals to advance to the selected site. We find that, even when defecting is the rational choice for any agent, under certain conditions, cooperators can take advantage from mutual cooperation and leave the room more rapidly than defectors.

 

Game theory in models of pedestrian room evacuation
S. Bouzat, M. N. Kuperman

http://arxiv.org/abs/1311.1708

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Motility at the Origin of Life: Its Characterization and a Model

Due to recent advances in synthetic biology and artificial life, the origin of life is currently a hot topic of research. We review the literature and argue that the two traditionally competing replicator-first and metabolism-first approaches are merging into one integrated theory of individuation and evolution. We contribute to the maturation of this more inclusive approach by highlighting some problematic assumptions that still lead to an impoverished conception of the phenomenon of life. In particular, we argue that the new consensus has so far failed to consider the relevance of intermediate time scales. We propose that an adequate theory of life must account for the fact that all living beings are situated in at least four distinct time scales, which are typically associated with metabolism, motility, development, and evolution. In this view, self-movement, adaptive behavior, and morphological changes could have already been present at the origin of life. In order to illustrate this possibility, we analyze a minimal model of lifelike phenomena, namely, of precarious, individuated, dissipative structures that can be found in simple reaction-diffusion systems. Based on our analysis, we suggest that processes on intermediate time scales could have already been operative in prebiotic systems. They may have facilitated and constrained changes occurring in the faster- and slower-paced time scales of chemical self-individuation and evolution by natural selection, respectively.

 

Motility at the Origin of Life: Its Characterization and a Model
Tom Froese, Nathaniel Virgo, Takashi Ikegami

Artificial Life

http://dx.doi.org/10.1162/ARTL_a_00096

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An exploration of social identity: The geography and politics of news-sharing communities in twitter

The importance of collective social action in current events is manifest in the Arab Spring and Occupy movements. Electronic social media have become a pervasive channel for social interactions, and a basis of collective social response to information. The study of social media can reveal how individual actions combine to become the collective dynamics of society. Characterizing the groups that form spontaneously may reveal both how individuals self-identify and how they will act together. Here we map the social, political, and geographical properties of news-sharing communities on Twitter, a popular microblogging platform. We track user-generated messages that contain links to New York Times online articles and we label users according to the topic of the links they share, their geographic location, and their self-descriptive keywords. When users are clustered based on who follows whom in Twitter, we find social groups separate by whether they are interested in local (NY), national (US) or global (cosmopolitan) issues. The national group subdivides into liberal, conservative and other, the latter being a diverse but mostly business oriented group with sports, arts, and other splinters. The national political groups are based across the US but are distinct from the national group that is broadly interested in a variety of topics. A person who is cosmopolitan associates with others who are cosmopolitan, and a US liberal/conservative associates with others who are US liberal/conservative, creating separated social groups with those identities. The existence of “citizens” of local, national, and cosmopolitan communities is a basis for dialog and action at each of these levels of societal organization.

 

An exploration of social identity: The geography and politics of news-sharing communities in twitter
AmaÇ HerdaĞdelen, Wenyun Zuo, Alexander Gard-Murray, Yaneer Bar-Yam

Complexity
Volume 19, Issue 2, pages 10–20, November/December 2013

http://dx.doi.org/10.1002/cplx.21457

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