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Class Imbalance strategies
Help · 24 May 2024, 21:03 · 2

Hello,

I am hoping someone can help advise me on handling the class imbalances. I am using DETR, but I am not sure how I can 'weight' the lesser classes to be higher and vice-versa for the Tin class.

Some ideas I am looking into trying -

1. train 3 binary DETR models, one for Tin class, then use transfer learning for the classes with less training examples. At inference, run each model on each image and decide on a way to choose overlapping bounding boxes.

2. train an ensemble of Tin-downsampled datasets and create upsampled augmented undersampled Other and Thatched classes.

3. just train a single Detr and weight the imbalanced classes accordingly.

Currently am stuck on 1. I modified the beginner huggingface notebook to only use Tin classes. Basically switched it to binary object detector, But I can't get it to output any bounding boxes at inference ... it just gives really low scores for them.

Any advice or help with where I should focus woudl be great. At this point, I just want to get something working.

Thanks,

Ian

Discussion 2 answers

I used DETR but did not have much success with it. Personally I found most success with Pytorch FasterRCNN. So if you just want to get a working model I would try and use that. The tutorial they give is pretty good and easy to follow if you havent used it before.

29 May 2024, 23:14
Upvotes 0

I think option 3 and some data augmentation techniques (such as mosaic) would suffice.

4 Jun 2024, 09:24
Upvotes 0