Open-Set Living Need Prediction with Large Language Models

Living needs are the needs people generate in their daily lives for survival and well-being. On life service platforms like Meituan, user purchases are driven by living needs, making accurate living need predictions crucial for personalized service recommendations. Traditional approaches treat this prediction as a closed-set classification problem, severely limiting their ability to capture the diversity and complexity of living needs. In this work, we redefine living need prediction as an open-set classification problem and propose PIGEON, a novel system leveraging large language models (LLMs) for unrestricted need prediction. PIGEON first employs a behavior-aware record retriever to help LLMs understand user preferences, then incorporates Maslow's hierarchy of needs to align predictions with human living needs. For evaluation and application, we design a recall module based on a fine-tuned text embedding model that links flexible need descriptions to appropriate life services. Extensive experiments on realworld datasets demonstrate that PIGEON significantly outperforms closed-set approaches on need-based life service recall by an average of 19.37%. Human evaluation validates the reasonableness and specificity of our predictions. Additionally, we employ instruction tuning to enable smaller LLMs to achieve competitive performance, supporting practical deployment. * Corresponding author. 1 meituan.com User Time Location Historical behaviors in similar spatiotemporal contexts Going to cocktail bars, eating BBQ, having hot pot, going to Izakaya, watching movies, playing bowling … 8:00 pm Commercial Street • Physiological Needs -Basic Diet * Home meals * Restaurant dining -Housing Needs * Basic living space * Quality living environment -Daily Living Supplies * Essential supplies * Fresh groceries • Safety Needs -Health Protection * General wellness maintenance * Specialized medical care * Preventive healthcare -Home Security * Property protection * Safety maintenance -Living Environment * Cleaning services * Environmental maintenance • Social Belonging Needs -Group Activities * Dining and social venues * Leisure and entertainment activities -Family and Parent-Child Interaction * Parent-child activities and entertainment * Family celebrations and event organization • Esteem Needs -Knowledge Development * Educational training * Arts and skill development -Career Growth * Academic advancement * Professional skills • Self-Actualization Needs -Cultural and Artistic Pursuits * Cultural experiences and exhibitions * Artistic creation and expression -Travel and Experiential Activities * Travel and sightseeing * Outdoor and experiential activities