Print

Print


***** To join INSNA, visit http://www.insna.org *****

If you missed Sunbelt XXXII, you missed a great learning opportunity that was also a great time. Three cheers for Tom Valenti and the rest of the team that put this together for us.

Still a bit jet-lagged here in Japan. The following recommendations are simply what caught my blurry eyes this morning. 


Complexity Digest 2012.06 2012/03/16



Predictable. Scary. Bears repeating.

01. Navigating the Anthropocene: Improving Earth System Governance , Science

Excerpt: Science assessments indicate that human activities are moving several
of Earth's sub-systems outside the range of natural variability typical for the
previous 500,000 years. Human societies must now change course and steer away
from critical tipping points in the Earth system that might lead to rapid and
irreversible change. This requires fundamental reorientation and restructuring
of national and international institutions toward more effective Earth system
governance and planetary stewardship.

* [1] Navigating the Anthropocene: Improving Earth System Governance, F.
Biermann, et al., 2012/03/16, DOI: 10.1126/science.1217255, Science Vol. 335 no.
6074 pp. 1306-1307

[1] http://dx.doi.org/10.1126/science.1217255

_________________________________________________________________

"global, population-wide behavior that one observes often bears no relation to the individual processes it stems from."
What does this signify for agent-based modeling?

02. From Local to Global Dilemmas in Social Networks , PLoS ONE

Excerpt: Social networks affect in such a fundamental way the dynamics of the
population they support that the global, population-wide behavior that one
observes often bears no relation to the individual processes it stems from. Up
to now, linking the global networked dynamics to such individual mechanisms has
remained elusive.

* [2] From Local to Global Dilemmas in Social Networks, Pinheiro FL , Pacheco JM
, Santos FC, March 2012, DOI: 10.1371/journal.pone.0032114, PLoS ONE 7(2):
e32114
* Contributed by [3] Segismundo

[2] http://dx.doi.org/10.1371/journal.pone.0032114
[3] http://segis.name

_________________________________________________________________

Humpback whales and quantum mechanics. Is this the Dao of Physics or something
really cool? Looks like the "reduction phenomenon" is something worth learning about.

03. Universal Theory on Growth and Mixing , PNAS

Summary: What do humpback whales returning to calve in the waters of Maui have
to do with the ground state energy of a quantum system?
Both exhibit a mathematical property called the "reduction phenomenon", which
can be described very simply:
mixing reduces growth, and differential growth selects for reduced mixing.
The phenomenon underlies the Reduction Principle for the evolution of
recombination, mutation, and dispersal rates, as well as recent results in
reaction-diffusion models of dispersal.
Animals returning to their birth places to give birth exemplify operation of the
Reduction Principle through philopatry.
In molecular genetics it is manifest as error-free DNA repair.
In cultural evolution models it is manifest as traditionalism.
Yet, departures from reduction are abundant, such as recombination and
dispersal.
How can sense be made of the complexity of outcomes?
Two new papers describes mathematical results that extend the reduction
phenomenon to infinite dimensional operators, and investigate departures from
reduction which follow the "Principle of Partial Control".
A new population statistic, the "fitness-abundance covariance", links ecological
properties to the reduction phenomenon.
See Also: The Evolution of Dispersal in Random Environments and The Principle of
Partial Control, Lee Altenberg DOI: 10.1890/11-1136.1

* [4] Resolvent positive linear operators exhibit the reduction phenomenon, Lee
Altenberg, 2012/02/22, DOI: 10.1073/pnas.1113833109, PNAS

[4] http://dx.doi.org/10.1073/pnas.1113833109


_________________________________________________________________

OWS 2.0?

05. Jennifer Pahlka: Coding a better government , TED.com

About this talk: Can government be run like the Internet, permissionless and
open? Coder and activist Jennifer Pahlka believes it can -- and that apps, built
quickly and cheaply, are a powerful new way to connect citizens to their
governments -- and their neighbors.

* [7] Jennifer Pahlka: Coding a better government, 2012/03, TED.com
* VIDEO - [8] Watch this talk

[7] http://www.ted.com/talks/jennifer_pahlka_coding_a_better_government.html
[8] http://www.ted.com/talks/jennifer_pahlka_coding_a_better_government.html

_________________________________________________________________

* [15] The Future of Complexity Engineering, Frei, R. and Di Marzo Serugendo, G,
2012/03, Central European Journal of Engineering

[15] http://www.reginafrei.ch/pdf/future-of-CE-v11.pdf

_________________________________________________________________

Fundamental insight or Luddite obfuscation? You be the judge.

07. Learning, Social Intelligence and the Turing Test - why an "out-of-the-box"
Turing Machine will not pass the Turing Test , arXiv

Excerpt: The Turing Test (TT) checks for human intelligence, rather than any
putative general intelligence. It involves repeated interaction requiring
learning in the form of adaption to the human conversation partner. It is a
macro-level post-hoc test in contrast to the definition of a Turing Machine
(TM), which is a prior micro-level definition. This raises the question of
whether learning is just another computational process, i.e. can be implemented
as a TM. Here we argue that learning or adaption is fundamentally different from
computation, though it does involve processes that can be seen as computations.
(…) We conclude three things, namely that: a purely "designed" TM will never
pass the TT; that there is no such thing as a general intelligence since it
necessary involves learning; and that learning/adaption and computation should
be clearly distinguished.

* [16] Learning, Social Intelligence and the Turing Test - why an
"out-of-the-box" Turing Machine will not pass the Turing Test, Bruce Edmonds and
Carlos Gershenson, 2012/03/15, arXiv:1203.3376

[16] http://arXiv.org/abs/1203.3376

________________________________________________________________


OK, I work in advertising, have long been fascinated with classic ideas about skirt heights and stock markets, and the Social Networks and Art session at Sunbelt XXXII was intriguing.
09. The Logic of Fashion Cycles , PLoS ONE

Excerpt: Many cultural traits exhibit volatile dynamics, commonly dubbed
fashions or fads. Here we show that realistic fashion-like dynamics emerge
spontaneously if individuals can copy others' preferences for cultural traits as
well as traits themselves.

* [18] The Logic of Fashion Cycles, Acerbi A , Ghirlanda S , Enquist M, March
2012, DOI: 10.1371/journal.pone.0032541, PLoS ONE 7(3): e32541
* Contributed by [19] Segismundo

[18] http://dx.doi.org/10.1371/journal.pone.0032541
[19] http://segis.name

_________________________________________________________________

Reports of non-human species engaged in cultural learning have been appearing in growing numbers. 
Let's see what this adds...

09.01. Adaptive strategies for cumulative cultural learning , Journal of
Theoretical Biology

Excerpt: Here we explore how cumulative culture influences the relative merits
of various pure and conditional learning strategies, including pure asocial and
social learning, critical social learning, conditional social learning and
individual refiner strategies.

* [20] Adaptive strategies for cumulative cultural learning, Ehn M , Laland K,
February 2012, DOI: 10.1016/j.jtbi.2012.02.004, Journal of Theoretical Biology,
in Press
* Contributed by [21] Segismundo

[20] http://dx.doi.org/10.1016/j.jtbi.2012.02.004
[21] http://segis.name



_________________________________________________________________

Market fundamentalists are going to hate this one.

12. Entropy and equilibrium state of free market models , Eur. Phys. J. B

Abstract: Many recent models of trade dynamics use the simple idea of wealth
exchanges among economic agents in order to obtain a stable or equilibrium
distribution of wealth among the agents. In particular, a plain analogy compares
the wealth in a society with the energy in a physical system, and the trade
between agents to the energy exchange between molecules during collisions. In
physical systems, the energy exchange among molecules leads to a state of
equipartition of the energy and to an equilibrium situation where the entropy is
a maximum. On the other hand, in a large class of exchange models, the system
converges to a very unequal condensed state, where one or a few agents
concentrate all the wealth of the society while the wide majority of agents
shares zero or almost zero fraction of the wealth. So, in those economic systems
a minimum entropy state is attained. We propose here an analytical model where
we investigate the effects of a particular class of economic exchanges that
minimize the entropy. By solving the model we discuss the conditions that can
drive the system to a state of minimum entropy, as well as the mechanisms to
recover a kind of equipartition of wealth.

* [24] Entropy and equilibrium state of free market models, J.R. Iglesias and
R.M.C. de Almeida, 2012/03/5, DOI: 10.1140/epjb/e2012-21036-1, Eur. Phys. J. B
85: 85

[24] http://dx.doi.org/10.1140/epjb/e2012-21036-1

_________________________________________________________________

For all us serious methods geeks.

13. Removing spurious interactions in complex networks , Phys. Rev. E

Abstract: Identifying and removing spurious links in complex networks is
meaningful for many real applications and is crucial for improving the
reliability of network data, which, in turn, can lead to a better understanding
of the highly interconnected nature of various social, biological, and
communication systems. In this paper, we study the features of different simple
spurious link elimination methods, revealing that they may lead to the
distortion of networks’ structural and dynamical properties. Accordingly, we
propose a hybrid method that combines similarity-based index and
edge-betweenness centrality. We show that our method can effectively eliminate
the spurious interactions while leaving the network connected and preserving the
network's functionalities.

* [25] Removing spurious interactions in complex networks, An Zeng and Giulio
Cimini, 2012/03/5, DOI: 10.1103/PhysRevE.85.036101, Phys. Rev. E 85, 036101

[25] http://dx.doi.org/10.1103/PhysRevE.85.036101


_________________________________________________________________

I'd like to hear what Tom Valenti has to say about this one.

15. Identifying influential spreaders and efficiently estimating the number of
infections in epidemic models: a path counting approach , arXiv

Abstract: We introduce a new method to efficiently approximate the number of
infections resulting from a given initially-infected node in a network of
susceptible individuals, based on counting the number of possible infection
paths of various lengths to each other node in the network. We analytically
study the properties of our method systematically, in particular demonstrating
different forms for SIS and SIR disease spreading (e.g. under the SIR model our
method counts self-avoiding walks). In comparison to existing methods to infer
the spreading efficiency of different nodes in the network (based on degree,
k-shell decomposition analysis and different centrality measures), our method
directly considers the spreading process, and as such is unique in providing
estimation of actual numbers of infections. Crucially, in simulating infections
on various real-world networks with the SIR model, we show that our walks-based
method improves the inference of effectiveness of nodes over a wide range of
infection rates compared to existing methods. We also analyse the trade-off
between estimate accuracy and computational cost of our method, showing that the
better accuracy here can still be obtained at a comparable computational cost to
other methods.

* [27] Identifying influential spreaders and efficiently estimating the number
of infections in epidemic models: a path counting approach, Frank Bauer, Joseph
T. Lizier, 2012/03/02, arXiv:1203.0502

[27] http://arXiv.org/abs/1203.0502

_________________________________________________________________
-- 
John McCreery
The Word Works, Ltd., Yokohama, JAPAN
Tel. +81-45-314-9324
[log in to unmask]
http://www.wordworks.jp/
_____________________________________________________________________ SOCNET is a service of INSNA, the professional association for social network researchers (http://www.insna.org). To unsubscribe, send an email message to [log in to unmask] containing the line UNSUBSCRIBE SOCNET in the body of the message.