Short Answer

Why does a dev/test distribution mismatch weaken confidence in a dev-set improvement?

Question: Answer in one to three sentences using the relationship between the dev and test distributions.

Sample answer: A dev-set improvement is measured on the dev distribution, which differs from the test distribution. Therefore, the team has additional uncertainty about whether the improvement will also raise test-set performance.

Key points:

  • The dev and test distributions are mismatched.
  • Improvement on the dev distribution may not transfer to test performance.

Rubric: The answer should state that the distributions differ and that this creates uncertainty about transferring dev-set gains to the test set.

0

1

Updated 2026-07-19

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