I am a PhD candidate in the Web Information Systems group at Delft University of Technology and a Guest Researcher at IBM. Supervised by Prof. Nava Tintarev (Maastricht University) and Benjamin Timmermans (IBM), my research focuses on understanding how algorithmic and cognitive biases in web search affect user attitudes on debated topics. I received my bachelor’s and master’s degrees in Psychology with a specialization in Behavioral Data Science from the University of Amsterdam and under supervision of Prof. Eric-Jan Wagenmakers. I have previously interned at IBM and worked as a research assistant for JASP. I live in Amsterdam with my dog Sepp.

Current Research Interests

Fueled by my interdisciplinary background, I like to work at the intersection of human behavior, statistics, and computer science. The central problem or starting point of my current research agenda is the search engine manipulation effect (SEME): when web search results on some debated topic (e.g., “Should zoos exist?”) favor one attitude over other attitudes, users tend to adopt this advantaged attitude. Mitigating SEME requires a thorough understanding of how, when, and why it occurs. That is why my PhD project focuses on understanding how algorithmic and cognitive biases affect user attitudes in this context. Specifically, I look at (1) how to accurately represent attitudes that are held by users or expressed in documents, (2) how to measure attitude-related ranking bias in web search results, and (3) what cognitive biases contribute to users’ attitude change in this context. A list of my publications is available here.

Side Projects

Every now and then I try to put my skills to good use outside of the research work that contributes to my dissertation. A few examples of this are my collaboration with researchers all over the world to identify what predicts desirable behavior related to the COVID-19 pandemic, my contribution to a recent large-scale many analysts project studying the effect of religiosity on well-being, and Statistical Test Finder, a comprehensive flowchart I created to help practitioners to find the right statistical test for their data. I also love talking about research methods and statistics in general, so feel free to reach out!


To get in touch, send me an email at drawstim@gmail.com. You can also find me in these places: Twitter, LinkedIn, GitHub, Stackoverflow, Open Science Framework, Google Scholar, Researchgate.

P.S.: This website was built using the amazing Noto Simple theme by Hitomi Seki.