Rainproof: An Umbrella To Shield Text Generators From Out-Of-Distribution Data
This addresses the need for safe and effective control mechanisms in deployed NLP models like chatbots, though it is incremental as it builds on existing OOD detection approaches.
The paper tackles the problem of out-of-distribution (OOD) detection for text generators by proposing RAINPROOF, a black-box framework using soft probabilities, and finds that it aligns better with task-specific performance metrics than traditional methods.
Implementing effective control mechanisms to ensure the proper functioning and security of deployed NLP models, from translation to chatbots, is essential. A key ingredient to ensure safe system behaviour is Out-Of-Distribution (OOD) detection, which aims to detect whether an input sample is statistically far from the training distribution. Although OOD detection is a widely covered topic in classification tasks, most methods rely on hidden features output by the encoder. In this work, we focus on leveraging soft-probabilities in a black-box framework, i.e. we can access the soft-predictions but not the internal states of the model. Our contributions include: (i) RAINPROOF a Relative informAItioN Projection OOD detection framework; and (ii) a more operational evaluation setting for OOD detection. Surprisingly, we find that OOD detection is not necessarily aligned with task-specific measures. The OOD detector may filter out samples well processed by the model and keep samples that are not, leading to weaker performance. Our results show that RAINPROOF provides OOD detection methods more aligned with task-specific performance metrics than traditional OOD detectors.