Enriching structured dataset via reasoning embeddings with few-shot learning for enhancing complaint classification
摘要
Public complaint classification is essential for effective municipal governance, yet remains challenging due to heterogeneous structured data, severe class imbalance, and limited ability of structured features to capture underlying representation. Unlike the existing studies that relied solely on the original features for end-to-end prediction, the contribution of this study lied in transforming large language models (LLMs) generated reasoning under few-shot learning into an explicit feature engineering step, where reasoning outputs are integrated with structured data and embedded to enrich representations. Extensive experiments were conducted on a real-world municipal complaint dataset containing over 48103 instances across 180 complaint subcategories. The best-performing configuration which combined Qwen3-14B, Paraphrase-Multilingual-Mpnet-Base-V2 embeddings, and Logistic Regression, achieved an average score of 44.8%, with an accuracy of 54%, an F1-score of 23.9%, and an Area Under the Curve of 92%. Moreover, error analysis revealed low class-wise error rates alongside reduced false positive and false negative rates, indicating balanced control over both false alarms and missed detections. The Shapiro-Wilk test rejected normality (statistic