Learn Before
Case Study

Plan the next review step after repeated image-classifier mistakes.

Case context: A team is developing a model that recognizes road signs from dashcam images. During manual review of dev set errors, they find that many mistakes come from images that are heavily blurred by motion. The team does not yet know a practical method for fixing blur-related failures. Some people want to stop discussing those examples and focus only on error types they already know how to address.

Question: According to sound error-analysis practice, what should the team do about the blurred images, and why?

Sample answer: They should keep the blurred images in the analysis. The team should count how often blur appears among the errors and examine those examples carefully, even if there is no immediate fix. The purpose of reviewing mistakes is to discover where the system is weak and to uncover promising directions for improvement, not only to track problems that are already easy to solve. Looking closely at the blurred cases may suggest new ideas, and measuring their frequency helps the team decide whether a dedicated effort to reduce blur-related errors is worth pursuing.

Key points:

  • Do not exclude errors just because they are hard to fix right away.
  • Error analysis is meant to reveal promising improvement opportunities.
  • Reviewing the blurred examples may lead to new ideas.
  • Counting how common blur is helps with prioritization.

Rubric: The response should advise keeping the blurred images in the error analysis, explain that the review is meant to identify promising directions rather than only easy fixes, and note that the frequency of blur-related errors helps the team decide whether to invest in a targeted solution.

0

1

Updated 2026-08-12

Contributors are:

Who are from:

Tags

Machine Learning

Deep Learning

Supervised Learning

Dive into Deep Learning @ D2L

Data Science

Machine Learning Strategy

Machine Learning Yearning @ DeepLearning.AI

Related