ULF: Unsupervised Labeling Function Correction using Cross-Validation for Weak Supervision
This work addresses noise reduction for practitioners using weak supervision, though it is incremental as it builds on existing cross-validation techniques.
The paper tackled noise in weak supervision by introducing ULF, an unsupervised algorithm that corrects labeling functions using cross-validation, resulting in enhanced weak supervision learning across multiple datasets without manual labeling.
A cost-effective alternative to manual data labeling is weak supervision (WS), where data samples are automatically annotated using a predefined set of labeling functions (LFs), rule-based mechanisms that generate artificial labels for the associated classes. In this work, we investigate noise reduction techniques for WS based on the principle of k-fold cross-validation. We introduce a new algorithm ULF for Unsupervised Labeling Function correction, which denoises WS data by leveraging models trained on all but some LFs to identify and correct biases specific to the held-out LFs. Specifically, ULF refines the allocation of LFs to classes by re-estimating this assignment on highly reliable cross-validated samples. Evaluation on multiple datasets confirms ULF's effectiveness in enhancing WS learning without the need for manual labeling.