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Just back from the International Communication Assoc. conf. in Washington.
Would have liked to have seen more network analysts there.
Looking forward to seeing you in Montreal.
   Barry Wellman

   Step by step, link by link, putting it together--Streisand/Sondheim
        The earth to be spannd, connected by network--Walt Whitman
              It's Always Something--Roseanne Roseannadanna

              A day like all days, filled with those events
          that alter and illuminate our times--Walter Cronkite
   Director, NetLab Network      			            FRSC
   Distinguished Visiting Scholar   Social Media Lab   Ryerson University
         Founder, International Network for Social Network Analysis
   NETWORKED: The New Social Operating System  Lee Rainie & Barry Wellman  

---------- Forwarded message ----------
Date: Mon, 27 May 2019 11:01:40 +0000
From: "[utf-8] Complexity Digest" <[log in to unmask]>
Reply-To: [log in to unmask]
To: "[utf-8] Barry" <[log in to unmask]>
Subject: [utf-8] Latest Complexity Digest Posts

Is the world small enough? ˙˙ A view from currencies

    Exchange rates are important indicators of the economic power of countries, directly affected by the international trading patterns and relations. Since almost every pair of countries in the globalized world are economically and financially related, exchange rates can be evaluated as nodes of a global financial network to make meaningful inferences.

In this study, a financial network approach is conducted by evaluating the movements of the most traded 35 currencies against gold between years 2005 and 2017. Using graph theory and statistical methods, the analysis of economic relations between currencies is carried out, supported with geographical and cultural inferences. A risk map of currencies is generated through the portfolio optimization. Another approach of applying various threshold levels for correlations to determine connections between currencies is also employed. Results indicate that there exists a saddle point for correlation threshold as 0.9 which results in a robust network topology that is highly modular and clustered, also dominantly displaying small-world and scale-free properties.

Is the world small enough? ˙˙ A view from currencies
Yusuf Yargi Baydilli and ˙˙lker Türker

International Journal of Modern Physics B Vol. 33, No. 12, 1950120 (2019)

Source: (

Functional and transcriptional connectivity of communities in breast cancer co-expression networks

    Transcriptional co-expression networks represent the concerted gene regulation programs by means of statistical inference of co-expression patterns. The rich phenomenology of transcriptional processes behind complex phenotypes such as cancer, is often captured (at least partially) in the connectivity structure of transcriptional co-expression networks. By analyzing the community structure of these networks, we may develop a deeper understanding of that phenomenology. We identified the modular structure of a transcriptional co-expression network obtained from breast cancer gene expression as well as a non-cancer adjacent breast tissue network as a control. We then analyzed the biological functions associated to the resulting communities by means of enrichment analysis. We also generated two projected networks for both, tumor and control networks: The first one is a projection to a network in which nodes are communities and edges represent topologically adjacent communities, indicating
co-expression patterns between them. For the second projection, a bipartite network was generated containing a layer of modules and a layer of biological processes, with links between modules and the functions in which they are enriched; from this bipartite network, a projection to the community layer was obtained. From the analysis of the communities and projections, we were able to discern distinctive patterns of regulation between tumors and controls. Even though the connectivity structure of transcriptional co-expression networks is quite different, the topology of the projected networks is somehow similar, indicating functional compartmentalization, in both tumor and control conditions. However, the biological functions represented in the corresponding modules resulted notably different, with the tumor network comprising functional modules enriched for well-known hallmarks of cancer.

Functional and transcriptional connectivity of communities in breast cancer co-expression networks
Guillermo de Anda-Jáuregui, Sergio Antonio Alcalá-Corona, Jesús Espinal-Enríquez and Enrique Hernández-Lemus
Applied Network Science 2019 4:22

Source: (

Murray Gell-Mann passes away at 89

Though he was best known for his contributions to particle physics, for 
which he won the 1969 Nobel prize in physics, Gell-Mann wanted to 
understand the ˙˙chain of relationships˙˙ that connected the universal 
laws of physics to complex systems like economies and human cultures. 
These two extremes of interest he described in his 1994 book, The Quark 
and the Jaguar, as ˙˙two aspects of nature˙˙on the one hand, the 
underlying physical laws of matter and the universe, and on the other, the 
rich fabric of the world that we perceive directly and of which we are a 

Source: (

Exogenous Rewards for Promoting Cooperation in Scale-Free Networks

    The design of mechanisms that encourage pro-social behaviours in populations of self-regarding agents is recognised as a major theoretical challenge within several areas of social, life and engineering sciences. When interference from external parties is considered, several heuristics have been identified as capable of engineering a desired collective behaviour at a minimal cost. However, these studies neglect the diverse nature of contexts and social structures that characterise real-world populations. Here we analyse the impact of diversity by means of scale-free interaction networks with high and low levels of clustering, and test various interference mechanisms using simulations of agents facing a cooperative dilemma. Our results show that interference on scale-free networks is not trivial and that distinct levels of clustering react differently to each interference mechanism. As such, we argue that no tailored response fits all scale-free networks and present which mechanisms are more
efficient at fostering cooperation in both types of networks. Finally, we discuss the pitfalls of considering reckless interference mechanisms.

Exogenous Rewards for Promoting Cooperation in Scale-Free Networks

Theodor Cimpeanu, The Anh Han, Francisco C. Santos

Source: (

A map is not the territory, or is it?

    ˙˙A map is not the territory˙˙ is a mantra introduced by the 
Polish-American mathematician Alfred Korzybski in an essay on the meaning 
of representation which he published in 1931. In it, he makes the very 
obvious point that an abstraction of something is not the thing itself and 
he uses the concept of the map to enforce this point. We all know what a 
map is. It is picture of the territory but with many details, in fact most 
details omitted. It may be similar to the thing but it can never be same. 
Korzybski˙˙s thesis is a closely argued treatise about how close a 
representation must be to the thing it is associated with and in grappling 
with this problem, he implicitly defines a model, echoing to an extent the 
concept of the ˙˙digital twin˙˙ that is preoccupying us somewhat in 
contemporary discussion of how we should build and use simulation models. 
In a previous editorial last year (Batty, 2018), I introduced the problem 
where I argued that such a digital twin must be an abstraction from the 
thing itself to which it is twinned. It may approach the thing itself but 
it can never be the same for the twin is a model as defined by an 
abstraction. Tomko and Winter (2019) took me to task in a rather gentle 
way for blurring this distinction in my saying that a twin is not the real 
thing but implying the twin needs to get as close as possible to the real 
thing. If we do get close, then the abstraction and the thing itself begin 
to merge. This does not quite reach the point where the twin is absorbed 
with the thing being abstracted but it does suggest that as our world ˙˙ 
whether it be societies, cities, building complexes, etc. ˙˙ evolves, then 
the digital landscape which hitherto we have regarded as something rather 
separate from the actual landscape begin to merge, producing a new 
landscape that is a mixture of both. We will elaborate this point below 
for it is intrinsic to the way in which material and digital societies 
relate to one another.

A map is not the territory, or is it?
Michael Batty
Environment and Planning B: Urban Analytics and City Science

Source: (

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