A Note on the Inception Score

goal: find a generative distribution s.t. p_G(x) ~ p_R(x) according to some metric

• an explicit p_G not availble
• findings
  • common metrics do not correlate with each other
  • no clear evidence that any model is better
    • up to a hyperparameter search

IS

• qualities: image contains clear objects, high diversity of images from all classes in ImageNet
  • note: unbalanced class distribution in ImageNet
  • correlate well with human judgement of quality
• problems
  • suboptimalities: depends on implementation / sensitive to weight change
  • usage: models trained other than ImageNet yields misleading results