HYDRA: Hypergradient Data Relevance Analysis for Interpreting Deep Neural Networks
Yuanyuan Chen, Boyang Li, Han Yu, Pengcheng Wu, Chunyan Miao
TL;DR
HYDRA (Hypergradient Data Relevance Analysis) reframes DNN predictions as outcomes of training data by unrolling the test-loss hypergradient with respect to per-sample weights along the full optimization trajectory. It introduces a Hessian-free approximation for efficient data-credit computation and provides theoretical bounds on the approximation error, demonstrated to be accurate and more stable than influence functions. Empirically, HyDRA identifies influential or mislabeled data with higher fidelity, delivers substantial speedups (up to ~971×) over Hessian-based approaches, and aids debugging by effectively removing mislabeled examples. The work offers a scalable, data-centric interpretability tool with practical impact on data debugging, bias assessment, and transparency in DNN predictions.
Abstract
The behaviors of deep neural networks (DNNs) are notoriously resistant to human interpretations. In this paper, we propose Hypergradient Data Relevance Analysis, or HYDRA, which interprets the predictions made by DNNs as effects of their training data. Existing approaches generally estimate data contributions around the final model parameters and ignore how the training data shape the optimization trajectory. By unrolling the hypergradient of test loss w.r.t. the weights of training data, HYDRA assesses the contribution of training data toward test data points throughout the training trajectory. In order to accelerate computation, we remove the Hessian from the calculation and prove that, under moderate conditions, the approximation error is bounded. Corroborating this theoretical claim, empirical results indicate the error is indeed small. In addition, we quantitatively demonstrate that HYDRA outperforms influence functions in accurately estimating data contribution and detecting noisy data labels. The source code is available at https://github.com/cyyever/aaai_hydra_8686.
