Hallucination Detection in LLMs Using Spectral Features of Attention Maps
This work addresses hallucination detection for safety-critical applications, representing an incremental improvement over existing attention-based methods.
The paper tackled the problem of detecting hallucinations in Large Language Models by analyzing spectral features of attention maps, achieving state-of-the-art performance among attention-based methods.
Large Language Models (LLMs) have demonstrated remarkable performance across various tasks but remain prone to hallucinations. Detecting hallucinations is essential for safety-critical applications, and recent methods leverage attention map properties to this end, though their effectiveness remains limited. In this work, we investigate the spectral features of attention maps by interpreting them as adjacency matrices of graph structures. We propose the $\text{LapEigvals}$ method, which utilises the top-$k$ eigenvalues of the Laplacian matrix derived from the attention maps as an input to hallucination detection probes. Empirical evaluations demonstrate that our approach achieves state-of-the-art hallucination detection performance among attention-based methods. Extensive ablation studies further highlight the robustness and generalisation of $\text{LapEigvals}$, paving the way for future advancements in the hallucination detection domain.