Projects

This is a selection of projects I’ve worked on in the past years.

Social Protocols Link to heading

The social protocols organization has the goal of creating algorithms to enhance collective intelligence. We consider a social protocol to be a set of rules and mechanisms that govern the interaction of users on social computing platforms. We started out by analyzing and reverse engineering the Hacker News algorithm since it is very simple by design and has been working pretty well for many years. We scraped the frontpage every minute for several months to obtain a time series data set (available here) where we could exactly recreate a story’s entire lifecycle. We then developed a new metric to measure attention for stories and estimated how much a story over- or underperformed and built a hacker news client where we display this metric for users to play around with it. Currently, we are applying our learnings from these projects on a new social networking site that we hope will enable large-scale constructive discussion and collective intelligence. All our work is open source and available on GitHub.

Social Dynamics Hub Link to heading

Researching social dynamics, opinion dynamics, and agent-based modeling in my time at RWTH Aachen University, I wrote a lot of introductory material on those topic, which we turned into online learning resources. I built an educational R library (gridabm) to build and animate grid agent-based models in a few lines of code and wrote lots of explanations on cellular automata, agent-based modeling, emergent phenomena in complex social systems, and other related topics. The site is open source and contribution is encouraged (see the publication). All code for this project is available on GitHub.

ProcessMining.jl Link to heading

I got pretty interested in process mining a while ago at university. Most people use the pm4py Python library to do process mining. However, since Python is a little slow and process mining algorithms can be quite expensive, I thought that the Julia programming language would be a better fit for the task. I built a process mining library for Julia and although it turned out to be more of a toy project, the library provides a complete process mining workflow with a working implementation of the alpha algorithm, a basic XES parser, several process models, and plotting functionality. Implementing the alpha algorithm was particularly difficult and taught me a lot. I may continue working on this project in the future. The repository is on GitHub.

Citation Networks Link to heading

The popular R library bibliometrix has a lot of useful tools to analyze large datasets of scientific publications as provided by databases such as Scopus. Surprisingly to me at the time, these do not include a tool to visualize or even analyze the citation relation, i.e., a directed graph where an edge (a, b) represents the relation “publication A cites publication B”. I suspect that this is because this relation is not reliably provided by the major scientific publication databases. To me, the citation relation was the most interesting graph to analyze, so I built a tool where it could be extracted from database outputs from Scopus, as well as some analysis tooling as described here.

SEMinR Link to heading

I co-wrote a plotting module for the popular R library seminr which implements structural equation modeling (SEM). Representing SEMs as directed graphs make them more accessible for explanation and easier to reason about. The tool we built provides quick access to a graphical representation of a SEM and it is able to produce publication-ready visualizations as well.

BCACrypt Link to heading

This was really just a toy project since I was (and still am) fascinated by cellular automata and cryptography. Reversible block cellular automata can be used for symmetric encryption which to me was a really unexpected connection. So I implemented an encryption scheme in Julia using the block cellular automata rules Critters and Tron. Encryption and decryption do work, although I certainly doubt that my library constitutes a secure encryption algorithm. If you find it interesting though, trying to break this encryption and decrypt a message encrypted with this scheme could be a fun learning project. The library provides a hacky tool to animate the BCAs as well, so playing around with that could also be fun. The code is on GitHub.

My Dotfiles Link to heading

Perhaps a bit strange to include my dotfiles in my project list, but I’ a passionate Linux user and I’ve put considerable effort in them. I’ve learned tons from studying other peoples’ dotfiles, so why not include mine here too?

Currently, I run NixOS and I’m pretty happy with it. If you’re interested in how I setup my computer, you can check out my dotfiles here.