Attention-Driven Dual-Level Cost-Sensitive Stacking for Financial Statement Fraud Detection

Detecting fraud in financial statements is essential for maintaining transparency and accountability. In this study, we propose a novel dual-level cost-sensitive stacking ensemble framework for financial fraud detection, integrating a range of traditional classifiers with a state-of-the-art attention-based neural model. Our approach applies cost weighting at both the base and meta levels to amplify minority-class detection and pairs it with SMOTE-based oversampling. Additionally, we combine heterogeneous financial ratios and raw accounting variables in a single pipeline, enabling the model to derive new ratio-like features that capture real-world financial complexity.Comprehensive experiments demonstrate that this dual-layer cost weighting, together with SMOTE, significantly enhances fraud detection. Notably, incorporating TabTransformer within the ensemble achieves an AUC of 89.10% on a benchmark dataset, surpassing single-stage cost-sensitive methods and prior studies. These findings underscore how multi-level cost sensitivity, attention-driven modeling, and domain-specific feature integration can effectively tackle skewed data in financial statement fraud. Our framework offers an adaptable and robust solution for class-imbalanced financial contexts and may extend to related anomaly detection scenarios across various domains.