BTKD++: Beyond Teachers by Critically Distilling Knowledge from Teacher’s Bias
摘要
Existing knowledge distillation methods indiscriminately transfer knowledge from teacher networks, including output-level decisional biases, i.e., incorrect final predictions that can mislead student learning and limit student performance. We challenge this paradigm by proposing BTKD++, a framework that systematically filters and rectifies teacher’s output-level biased knowledge into corrective signals. Our approach partitions training data into Easy Tasks (correct teacher predictions) and Hard Tasks (incorrect predictions), then applies bias elimination and rectification modules orchestrated by dynamic learning curriculum. We provide an interpretive information-theoretic abstraction to explain the observed competence-threshold phenomenon, under which bias rectification becomes more effective when teacher errors contain sufficiently structured corrective information. BTKD++ demonstrates broad applicability across classification, detection, and segmentation tasks when task outputs are equipped with suitable probabilistic interfaces, and shows consistent effectiveness across CNNs, Transformers, and State-Space Models. Extensive experiments show consistent student-teacher transcendence, establishing new state-of-the-art results. This work redefines knowledge distillation from blind mimicry to critical learning, proving that students can surpass teachers through principled bias correction. The source code is available at https://github.com/smartyige/BTKD.