Active Class Incremental Learning for Imbalanced Datasets

Incremental Learning (IL) allows AI systems to adapt to streamed data. Most existing algorithms make two strong hypotheses which reduce the realism of the incremental scenario: (1) new data are assumed to be readily annotated when streamed and (2) tests are run with balanced datasets while most real-life datasets are actually imbalanced. These hypotheses are discarded and the resulting challenges are tackled with a combination of active and imbalanced learning. We introduce sample acquisition functions which tackle imbalance and are compatible with IL constraints. We also consider IL as an imbalanced learning problem instead of the established usage of knowledge distillation against catastrophic forgetting. Here, imbalance effects are reduced during inference through class prediction scaling. Evaluation is done with four visual datasets and compares existing and proposed sample acquisition functions. Results indicate that the proposed contributions have a positive effect and reduce the gap between active and standard IL performance.Comment: Accepted in IPCV workshop from ECCV202

Mining the Web With Active Hidden Markov Models

Introduction Given the enormous amounts of information available only in unstructured or semi-structured textual documents, tools for information extraction (IE) have become enormously important. IE tools identify the relevant information in such documents and convert it into a structured format such as a database or an XML document. While first IE algorithms were hand-crafted sets of rules, researchers soon turned to learning extraction rules from hand-labeled documents. Unfortunately, rule-based approaches sometimes fail to provide the necessary robustness against the inherent variability of document structure, which has led to the recent interest in the use of hidden Markov models (HMMs) [1] for this purpose. Speech recognition and computational biochemistry are well-known applications of HMMs. Markov model algorithms that are used for part-ofspeech tagging, as well as known hidden Markov models for information extraction [1] require the training documents to b