Quantifying the Privacy-Utility Trade-off in GPS-based Daily Stress Recognition using Semantic Features

Abstract: Psychological stress is a widespread issue that significantly impacts student well-being and academic performance. Effective remote stress recognition is crucial, yet existing methods often rely on wearable devices or GPS-based clustering techniques that pose privacy risks. In this study, we introduce a novel, end-to-end privacy-enhanced framework for semantic location encoding using a self-hosted OSM engine and an LLM-bootstrapped static map. We rigorously quantify the privacy-utility trade-off and demonstrate (via LOSO validation) that our Privacy-Aware (PA) model achieves performance statistically indistinguishable from a non-private model, proving that utility does not require sacrificing privacy. Feature importance analysis highlights that recreational activity time, working time, and travel time play a significant role in stress recognition.