agent-based model



Elective: Complex and Adaptive Systems


Create an Complex and Adaptive Systems which creates value for designers.


Improvement of a simulation of an online community based on the work of Ren and Kraut.



The paper proposes an addition to Ren and Kraut’s model of online communities, to be usable for online community designers. The model holds up to newly introduced social science theory 90-9-1 rule and thus can be seen as a robust model. In this paper I found which parameters decrease the amount of lurkers and increase the amount of posters and thus inform community designer about the design decisions they have to make. Only a limited amount of parameters are explored and the model shows a lot of potential for further research and understanding of online communities.


Key learning points: CAS, Programming, networks

Using Netlogo was quite a challenge since the way of programming isn’t the same as normally. Therefore getting started form scratch was difficult. Luckily I came across a model made in Netlogo made by Ren and Kraut. Most of the heuristics were based on the work of them. When opening the model however, I encountered many problems. Therefore my goal was to make the model usable for community mangers without any programming experience. I broadened my understanding of communities and came to the simple insight that to keep a stable community, you need as much newcomers as you need members becoming non-active. Therefore it always looks a community is growing, however it are the newcomers that make sure the activity level remains the same and the community doesn’t fade away. The model can be used as one of my tools for Acamponie to explain platform designers about network dynamics online.