Category Archives: Publications

ICT for Cities

Here is a chapter I wrote for a book on “Rapid Urbanization and the Future of Transforming Cities in Asia”.  It is edited by Professor Genie Birch of the University of Pennsylvania.   The book will be published early in 2014 so please do not distribute widely.  The chapter deals mainly with the problem that municipal governments have been slow to adopt ICT as an agent of transformation.  It does not deal specifically with smart cities.

Out-of-equilibrium actor-based system-dynamic modeling of the economics of climate change

A paper “Out-of-equilibrium actor-based system-dynamic modeling of the economics of climate change” by Dmitry V. Kovalevsky and Klaus Hasselmann is a contribution to GSS Preparatory Workshop for the 3rd Open Global Systems Science Conference (2014), 29-30 October 2013, Beijing, China.

The actor-based system-dynamic approach to integrated assessment modeling is illustrated for a simple model hierarchy consisting of a basic out-of-equilibrium model of economic growth and several alternative extensions demonstrating both stable and unstable dynamics. The evolution of the economy is governed by the strategies of key economic actors (aggregate producer and aggregate consumer) demonstrating that very different evolution paths can result from alternative hypotheses regarding actor behaviour. The paper serves as illustration of more realistic models designed within the MADIAMS (Multi-Actor Dynamic Integrated Assessment Model System) hierarchy to assess the long-term impacts of climate mitigation.

Research that lead to results presented in the paper has been performed in the framework of on-going EU FP7 COMPLEX project (“Knowledge based climate mitigation systems for a low carbon economy”) and projects solicited by the Russian Foundation for Basic Research.

Download: Kovalevsky D.V., Hasselmann K., 2013. Out-of-equilibrium actor-based system-dynamic modeling of the economics of climate change

GSS: Towards a Research Program for Global Systems Science


Carlo Jaeger, Patrik Jansson, Sander van der Leeuw, Michael Resch and J. David Tàbara

Conference Version, prepared for the Second Open Global Systems Science Conference
June 10-12, 2013, Brussels



Written on the basis of:

–       the first open global systems science – GSS – conference (Brussels, November 2012)
–       seven subsequent workshops on GSS
–       insights from the EU – FET consultation process on GSS
–       contributions to the GSS blog:


With thanks for contributions and comments by:

Alex Serret, Amit Kapoor, Andrés Gómez-Lievano, Angela Wilkinson, Anna Mengolini, Anna Mutule, Antoine Mandel, Antonio Fernandez, Antonio Lucio, Armin Haas, Ben Ruddell, Brad Allenby, Brandon Fuller, Carlo C. Jaeger, Catalina Spataru, Catalina Spataru, Cezar Ionescu, Chris B. Davis, Chris Kennedy, Christian Heimgartner, Christian Svansfeldt, Christian Svansfeldt, Christopher L. Barrett, Chuck Redman, Ciro Cattuto, Colin Harrison, David Pearce, David Simmonds, David Tuckett, Deborah Strumsky, Denise Pumain, Devdatt Dubhashi, Diana Mangalagiu, Doyne Farmer, Emile Chappin, Eric Boix, Eric Miller, Ettore Bompard, Filippo Addarii, Folke Snickars, Fonz Dekkers, Franziska Schuetze, Frédéric Sgard, Geoffrey Cape, Geoffrey West, Gerard P.J. Dijkema, Gianluca Fulli, Greg Lindsay, Guido Caldarelli, Henry Wynn, Herman De Meer, Hugh Kelly, Igor Nikolic, Ilan Chabay, Ilona Heldal, J. David Tàbara, Jan Bialek, Jeff Johnson, José Lobo, José Ramasco, José S. Sanchez Torres, Joseph Tainter, Karen Seto, Kevin Stolarick, Leo Camiciotti, Linda Steg, Lisa Amini, Lisa Flatley, Loreto, Luis Bettencourt, Luis Willumsen, Madhav V. Marathe, Manfred Laubichler, Marc Barthélemy, Marcelo Masera, Marco Aiello, Marco Ajmone, Maria Rosa Casals, Mario Rasetti, Martin Elsman, Maxi San Miguel, Melanie Fasche, Merijn Terheggen, Michael Batty, Michael Resch, Michael Smith, Michail Fragkias, Michel Morvan, Mihnea Costantinescu, Mikhail Chester, Nil Gilbert, Oliva García-Cantú, Patricia Reiter, Patrik Jansson, Paul Hearn, Paulien Herder, Pedro Ballesteros, Peter Nijkamp, Ralph Dum, Ricardo Baeza-Yates, Ricardo Herranz, Rudiger Ahrend, Sandeep Goyal, Sander van der Leeuw, Sibylle Schupp, Silvano Cincotti, Stanislav Sobolevsky, Stefano Battiston, Steven Bishop, Sylvain Haon, Temis Taylor, Vittorio Loretto, William J. Nuttall, William Nuttall, Zofia Lukszo

Testing versus proving in climate impact research

Another recent paper by Cezar Ionescu and Patrik Jansson is also freely available: Full text + abstract.


Higher-order properties arise naturally in some areas of climate impact research. For example, “vulnerability measures”, crucial in assessing the vulnerability to climate change of various regions and entities, must fulfill certain conditions which are best expressed by quantification over all increasing functions of an appropriate type. This kind of property is notoriously difficult to test. However, for the measures used in practice, it is quite easy to encode the property as a dependent type and prove it correct. Moreover, in scientific programming, one is often interested in correctness “up to implication”: the program would work as expected, say, if one would use real numbers instead of floating-point values. Such counterfactuals are impossible to test, but again, they can be easily encoded as types and proven. We show examples of such situations (encoded in Agda), encountered in actual vulnerability assessments.

Dependently-typed programming in scientific computing: Examples from economic modelling

Cezar Ionescu (at PIK) and Patrik Jansson (me, at Chalmers) have just got a paper accepted which fits in well in the GSS activity.

Pre-print + abstract


Computer simulations are essential in virtually every scientific discipline, even more so in those such as economics or climate change where the ability to make laboratory experiments is limited. Therefore, it is important to ensure that the models are implemented correctly, that they can be re-implemented and that the results can be reproduced. Typically, though, the models are described by a mixture of prose and mathematics which is insufficient for these purposes. We argue that using dependent types allows us to gradually reduce the gap between the mathematical description and the implementation, and we give examples from economic modelling. We discuss the consequences that our incremental approach has on programming style and the requirements it imposes on the dependently-typed programming languages used.

Out now: COMPLEXITY ECONOMICS – Complexity, Choices & Crises

The aim of this new journal is to enhance the knowledge and the know-how required for responsible action in the global economy of the 21st century. The global economy is likely to induce and experience transformations that we currently can hardly imagine. It will be characterized by complex networks combining local, national and global linkages, and by surprising interactions between the economy and its political, social and biophysical environments. In view of these new possibilities, the journal wants to preserve the insights developed since the days of Adam Smith in modes of analysis based on the conceptual device of representative agents. It will emphasize the opportunities provided by newer approaches to dynamic social networks, where actions are attributed to heterogeneous agents ranging from physical persons to multinational organizations, and where rationality has more aspects than the classical logical coherence. In view of this perspective, multi-agent modeling of complex economic networks will be an important focus of the journal.

Articles of the first issue can be accessed free of charge on:

Contents and ordering details: