After defending his dissertation last October, Sebastian is now being honored by KU Eichstätt-Ingolstadt for his doctoral thesis “Modeling the complex relationship between task difficulty, accuracy, response time, and confidence.”
Click here for the full (German) article by KU Eichstätt
The research addresses a common everyday phenomenon: Why do we feel absolutely certain about some decisions while strongly doubting others? Using innovative experiments and mathematical models, the study demonstrates that this sense of certainty—scientifically known as “confidence”—arises from three key factors: the available evidence, information about the difficulty of the decision, and the time taken to decide.
In his dissertation, Sebastian Hellmann develops a novel theoretical model of confidence formation that can simultaneously explain decisions, confidence judgments, and response times. The work also includes empirical evidence from psychophysical experiments showing how people use both decision-relevant and decision-irrelevant information to calibrate their confidence. One particularly striking finding is that longer decision times can paradoxically lead to lower confidence—an effect with significant implications for real-world decision-making. These insights have important practical relevance in fields such as law (e.g., eyewitness testimony), medicine (e.g., diagnostics), and politics (e.g., dealing with uncertainty and misinformation). The study uniquely combines psychological experimentation with mathematical modeling, building a bridge between fundamental research and real-world application.