23 Jun

Contribution to the theory of dynamic networks in the study of the evolution of a city

by Clara Grácio, CIMA, Universidade de Évora

Mathematics Seminars at ISTAR – 24 Jun 2015, 11:30 Room C104, Building II, ISCTE-IUL

See the poster.

The theory of dynamical networks is concerned with systems of dynamical units coupled according to an underlying graph structure. It therefore investigates the interplay between dynamics and structure, between the temporal processes going on at the individual units and the static spatial structure linking them. It is a combination of graph theory and nonlinear dynamics. A representation through a network is very useful for describing the structure of many different complex systems. However, most real systems are formed by different subsystems that are interconnected. The number of systems and data known, is increasingly overwhelming, so powerful mathematical tools become necessary to achieve a deep knowledge and study of networks. In this talk is considered the theory of multilayer networks. “Viewing urban centres as “Living Labs” is a powerful new concept that is inspiring novel research leading to improved wellbeing and economic growth. We argue here that mathematicians can make an impact at the heart of this emerging interdisciplinary field, where hypotheses about human behavior must be quantified and tested against vast data sets and where decisions and interventions should be based on quantitative, testable predictions.” (say Peter Grindrod, Desmond J. Higham and Robert Mackay, Sep, 2014). Participate and give our contributions in this “laboratory” is our aim, considering as our case study and model calibration, the historical center of Évora, inscribed on UNESCO World Heritage List since 1986.

17 Jun

Who, What, Where, When, Why: Using the 5 Ws to communicate your research

A lay summary can be a useful approach to breaking down barriers and making research accessible. A good summary focuses on the important aspects of the research, but distilling this information is not always easy. A helpful starting point for identifying the key elements of a research story can be the 5 Ws. Andy Tattersall finds this approach might not work for every piece of research, but it has the potential to allow researchers to explore key themes and retain control of what they say and how they say it.

See more at the LSE Impact Blog

05 May

Seminar by Tadeusz Szuba (AGH University, Cracow)

Seminar by Tadeusz Szuba, DI-FCUL, 13 Mai at 14h

“Formal and computational model for A. Smith’s Invisible Hand paradigm as basis for quite new tools for market analysis and prediction”

Abstract:
“A. Smith’s statements provide clear hint on how to transform human as element of the market, into “business thinking and planning virtual processor”. Using this processor under concept of molecular model of computations, we are able to convert market into specific, nondeterministic, parallel computer. It is quite different computer, comparing to digital computer – most probably much more powerful but in different scale. It uses logic, not 0/1 Boolean algebra as basic calculus and processors move around computational space – do not take fixed positions. Computations are driven by abstract “value” – not by operating system. This computational nature is like second side of coin or another dimension of the market. This idea leads to perception and formalization of A. Smith Invisible Hand of Market (ASIHM) as a computer: ASIHM-computer. This computer is self-programming and is performing computations not only for market optimization & stabilization, but also can act as “discoverer” of e.g. new technologies necessary for market (technical optimization). ASIH-computer is specific for every market, since reflects it’ nature and mentality of agents. Most probably also rules of social behavior can be discovered by ASIHM-computer (social optimization). Threads of ASIHM-computer calculations are not visible for single agent, since it participates only in one or just few steps of such calculations. Only economists can identify architecture of this computer and what computations are performed. Perceiving market as “thinking subject” will lead to quite different tools for market analysis and prediction. It can be done in such way, that at first economists with help of specialists from theory of computations will construct simulation model of ASIHM-computer for given market (approximation). Next, this model will be investigated on what it can calculate, how fast and what way it will react to market disturbances, etc. ASIHM-computer concept will imply a lot of theoretical research. To tackle this concept, EU Grant & team is necessary + approx. 5 years of work. In general, ASIHM-computer is similar to swarm-computer (ants, honeybees); however, agents are much more intelligent.”

Tadeusz Szuba has received Ph. D. in AI in 1979. In 1975 – 1991 he was working on theory of intelligent, autonomous machines (intelligent excavator). Machines were simulated in 3D animated computer graphics. In 1991-2001 he was associate professor in Department of Mathematics and Computer Science, Kuwait University. In 1993 he started to work on theory of Computational Collective Intelligence. This theory is published in book (SZUBA 2001). In 2002/2003 he was visiting associate professor at UMSL Univ. St. Louis, MO, USA. Since 2003 he is back at AGH University, Cracow Poland. Since 2009 he works on of Collective Intelligence theory applications, i.e. on formalization and simulation model of A. Smith Invisible Hand of Market. He tries to build formal and computational model of this phenomena. His teaching area is computer graphics, whereas research area is Collective Intelligence. He is head of Computer Graphics laboratory, head of postgraduate program in Computer Graphics and head of M. Sc. Program Modern Computer Graphics.

05 May

Postdoc position on Complex Socio-economic Systems, experiments and models

A postdoctoral researcher is expected to open to start on September 1st, 2015 as part of the EU Horizon 2020 project ‘Bridging the gap: from Individual Behaviour to the Socio-tEchnical MaN (IBSEN)’. The postdoctoral researcher will work at the Interdisciplinary Group of Complex Systems (Grupo Interdisciplinar de Sistemas Complejos, GISC) in the Department of Mathematics of UC3M, physically located in the Engineering Campus in the town of Leganés, 15 km south of the center of Madrid.

Full details here.

08 Apr

António Fonseca: new PhD thesis explaining the mechanisms of popularity

António Fonseca presented his PhD thesis on the 6th of April 2015, at ISCTE-IUL, entitled “Mecanismos de Popularidade e Difusão de Informação em Redes Sociais” (in Portuguese). The jury was composed by Ricardo Fonseca, Helder Coelho, Ernesto Costa, António Firmino da Costa, Luis Antunes, Pedro Lind, and Jorge Louçã (supervisor).

Abstract:
This research investigates the mechanisms of formation of popularity in society, assuming that popularity is generated though processes of information diffusion.
A static model of the distribution of popularity by various entities is here proposed and validated. It is demonstrated that it ts a probabilistic distribution of exponential growth of popularity. Complementarily, two dynamic models are proposed, representing the evolution of popularity. The first model, named Rami cation Model, is an exogenous impact model tracing the pro le of the typical evolution of popularity triggered by a single external event. The second one, called Epidemic Model, represents the process of popularity formation when arising from internal dissemination of messages within a community. All models are validated with experimental data.
A case study, concerning communication data collected during the
2011 elections in Portugal, allowed measuring the influence of popularity, generated through Social Communication, on opinion dynamics. Two sociophysics opinion dynamics models, based on the Brownian Model of Influence, and on the Social Impact Theory, were used to represent theoretically and quantitatively the dynamics of public debate in this period.
One of the most relevant results of the research concerns the understanding that the long term increasing of some entity’s popularity, as a result of communication processes between individuals, is independent from the entity subjective qualities, and it depends mainly from the communication processes being used.

07 Apr

Cooperation with the Indian Institute of Technology in Gandhinagar (IITGN)

Association between the Master Degrees of

Cognitive Sciences – Indian Institute of Technology Gandhinagar (IIT-GN)

and

Complexity Sciences – Lisbon University Institute (ISCTE-IUL)

The Indian Institute of Technology Gandhinagar (IITGN) and the Lisbon University Institute (ISCTE-IUL) signed in February 2015 an agreement of cooperation for the association of the two master degrees, regulating the exchange of students and visiting professors, and the development of joint teaching and research initiatives.

21 Mar

Joana Canelas: new master dissertation on Land-Use Intensity and Stability of Ecosystems

Joana Canelas presented her Master Dissertation entitled “Land-Use Intensity and Stability of Ecosystems”, on the 21th of March, 2014. The master dissertation was approved by the jury composed by Tiago Domingos (IST), Henrique Pereira (FCUL, supervisor), and Jorge Louçã (ISCTE-IUL).

Abstract:
Many organisms modify the surrounding environment in order to enhance the availability of resources, although the scale by which human societies do so is unprecedented. Through an ecological network model, we address the relation between ecosystem’s complexity, stability and productivity and how it is affected by land-use intensity, measured as the removal of biomass through harvest. We test different harvest intensities and distributions among species in order to assess the impact of land-use intensity in the ecosystem’s local stability, total biomass remaining and number of species extinctions. We found that land-use intensity triggers a decrease in the frequency of local stable communities. In this regard, our results support the hypothesis that a biomimetic harvest configuration could meet a rising food demand while halting biodiversity loss.

After concluding our Master in Complexity Sciences, Joana got a position of Research Associate at the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig. More recently, she obtained a grant from the University of Kent for developing PhD research on Biodiversity Management, at the School of Anthropology and Conservation (University of Kent).