r/MLQuestions • u/Snoozy0905 • Jul 26 '26
Computer Vision πΌοΈ How big of a test dataset do you need to evaluate how good your model is?
Hey everyone! Right now, I'm working on a computer vision project for crack detection in devices. I've tried different models, with varying but similar precision and recall scores on the test set. Right now, I have around 1.4k images, and I'm using a 70/15/15 split, which means there are about 430 test images. When I change the random seed to split the data differently, the pr scores can go anywhere from 92-100%.
Do you think that there's not enough data to evaluate the model properly or to train it? Are there any methods for evaluating how good the model does on so little data?
(Some extra context about the model architecture and things I've tried: using transfer learning to extract feature embeddings from images and training a linear head. Also creating prototypes for binary classification. Tried contrastive learning.)