Weakly supervised learning uses inaccurate or partial labels when fully detailed annotation is too slow, expensive, expertise-intensive, or unsupported by available tools. The labeling choice affects model options and ultimately constrains the product. section 6.2.4
Consider weak supervision when:
- Properly labeling each item would take too much time. section 6.2.4
- Too few qualified experts are available to cover enough data. section 6.2.4
- The required labeling toolset or level of detail is not ready. section 6.2.4
Medical-image labeling
A labeling task may ask whether image pixels represent malignancy. If pixel-level annotation is impractical, incomplete or inaccurate labels become a possible alternative, subject to product goals and needs. section 6.2.4
Figure 6.2 Various approaches to data labeling
Compare labeling approaches before choosing the annotation detail, tools, expertise, and model implications. section 6.2.4
