[Imagenette] The effect of resizing twice

Jeremy created the Imagenette/Imagewoof datasets [1] so we could try out our models without wasting too much time and money. For both datasets, we have access to full size images, as well as 320px and 160px versions.

@LessW2020 stumbled upon an interesting effect: if we train with 128px images resized from the full sized images, we get better results than when resized from the 160px version.

I ran some tests on Imagewoof, it’s quite significant. I wonder if it’s a common occurrence in DL projects.

Epochs Imagewoof-160 (a) Imagewoof-full_size (b) # of runs p-value
5 61.25% 63.89% 20 0.0001
20 80.87% 82.40% 3 0.043

[1] https://github.com/fastai/imagenette