Semantic Feature Engineering: Predicting Used Car Prices by Modeling Multi-criteria Human Decisions with LLMs
摘要
The market price of a used vehicle is the aggregate result of complex multi-criteria decision-making (MCDM) by prospective buyers. This paper posits that machine learning models can achieve superior predictive accuracy by directly modeling this underlying cognitive process. We contrast two methodologies on a dataset of over 100,000 Moroccan used cars. The classical approach uses state-of-the-art ensemble models on a feature set engineered with traditional encoding. Our novel approach, grounded in Information Integration Theory, replaces four key decision criteria—brand, model, year, and equipment—with a single, LLM-generated “Vehicle Desirability Score.” This score is explicitly designed to emulate an expert’s holistic evaluation, representing a proxy for a consumer’s cognitive utility assessment. Our findings show that models trained with this single, semantically aware feature significantly outperform their counterparts. For the top-performing XGBoost model, using the single “Vehicle Desirability Score” reduced the MAE by 18.4% and the RMSE by 17.6%, while increasing the