Welcome to the Chair of Systems Design

Our research can be best described as data driven modeling of complex systems, with particular emphasis on social, socio-technical, and socio-economic systems. We are a trully interdisciplinary team of about 20 people from various disciplines (statistical physics, applied mathematics, computer science, social science, engineering). And, yes, we do all the cool stuff, from big data analysis to multilayer network models, from social software engineering to predictions of scientific success - not to forget our research on polarization in political systems, cooperation in animal societies, and life cycles of R&D networks. Just click through our publications, funded projects, teaching or media coverage. 


Mastering the Challenges of our Digital Society

The workshop "Mastering the Challenges of our Digital Society" was held on 4th November 2016. This Risk Center workshop was organized by Prof. Frank Schweitzer and Dr. David Garcia together with Thomas Steiger from Zurich Insurance Company and addressed the challenges and opportunities of digitalization from the perspectives of three different stakeholders: citizens, companies and regulators.

More information on the workshop and the presentations of all speakers are available here.


SG Visualisation Contest

We have an internal contest on scientific visualisation here at the Chair of Systems Design. By participating in it, not only we add to our fun of doing research, but we also develop additional skills in visual communication.

As soon as there are a few submissions, the winner is decided by the group. The entry is then printed in large format, put in a frame and shown in the lounge area of the Chair.

Here we present the latest entry, submitted by Vahan Nanumyan.


Paper on Twitter presented at the IPP conference

The preprint related to our recent presentation at the The Internet, Policy & Politics Conference in Oxford is available at SocArxiv.

Check the online visualization of our results.


Invited Talk at ICSE 2016

We are proud to announce that our article From Aristotle to Ringelmann: a large-scale analysis of team productivity and coordination in Open Source Software projects was invited as Journal-First contribution for a talk at ICSE 2016, the world's premier software engineering venue. In our work, which is part of our research line on social software engineering, we use data science techniques to provide quantitative evidence for Brook's law in Open Source communities. On May 18 2016 Ingo Scholtes will present our results in the main research track of ICSE 2016 in Austin, TX, USA.


Book on Interconnected Networks

We are happy to anounce that the book "Interconnected Networks" which was edited by Antonios Garas and published by Springer is now available. The book contains selected contributions and provides both, an overview and an introduction to the emerging field of interconnected multilayered networks.


What we miss in network analysis

The analysis of relational data from a graph or network perspective has become a cornerstone of data mining. However, for data sets where additiional information like, e.g. the timing or ordering of relations are available, in a number of recent works we have shown that the network perspective can yield wrong results. In our latest work published in the European Physical Journal B we now offer a solution, namely the analysis of higher-order networks. We specifically show that this promising abstraction allows us to (i) generalize common path-based centrality measures to higher-order centralities, and that (ii) these higher-order measures better capture the real importance of nodes in time-evolving network topologies.


How does the productivity of teams scale with size?

We are happy to announce that our article "From Aristotle to Ringelmann: a large-scale analysis of team productivity and coordination in Open Source Software projects" has now been published in the journal Empirical Software Engineering. Using a data set of 58 OSS projects with more than 580,000 commits contributed by more than 30,000 developers, in this article we provide a large-scale analysis of the relation between size and productivity of software development teams.


Temporal Network Analysis in Python

We proudly present an in-depth educational tutorial showing how to analyze non-Markovian temporal networks using the python module pyTempNet which was recently developed at our chair. The tutorial features an interactive and hands-on introduction to our latest theoretical works on the analysis of time-stamped relational data. It demonstrates how our methods can be used to analyze the effect of order correlations in time-stamped network data, specifically showing how to analyze, simulate and visualize the effect of non-Markovian characteristics on dynamical processes.

The tutorial is available here.


Wikipedia research in the news

Our research in colaboration with GESIS Cologne has been featured in the news:

The results of our research are motivating editorial changes in Wikipedia:


Generalized Hypergeometric Ensembles

In our paper we introduce an ab initio class of statistical network ensembles based on a simple generative model of complex networks. We show that this class of ensembles provides a powerful framework for model selection in complex networks and a new approach to test the statistical signicance of community structures. The latest version of our paper"Generalized Hypergeometric Ensembles: Statistical Hypothesis Testing in Complex Networks" is available on ArXiv


How many developers does it take to complete a project?


Research covered by IEEE Software Blog


When Network Science Meets Software Engineering

On April 20, Ingo Scholtes will give an invited guest lecture in the special lecture series of the Elite Graduate Program in Software Engineering at Augsburg University, Germany. The lecture with the title "When Network Science meets Software Engineering" will introduce challenges and opportunities in the application of network-based data mining methods in the quantitative study of collaborative software engineering processes.


The Rise and Fall of R&D Networks

How are R&D networks structured? What are the driving forces behind the formation of inter-firm alliances? What are the reasons of the "rise and fall" trend exhibited by all industrial sectors in the last decades? These and more questions are answered in the latest version of our paper "The Rise and Fall of R&D Networks", now available on SSRN and ArXiv. Check also the nice visual example presented in the following video.