I'm training convolutional neural network on imbalanced dataset, which has 9 classes. Number of classes in order is, 3000-500-500- ..... goes like this. Of course I'm not waiting %100 accuracy, but when I use class weight function from Scikit Learn and use it on Keras' Fit Function, it didn't get better than %60.80, even I change the weights, still same situation.
When I didn't do any class weight operation, I get %68 accuracy.
Also I also used smaller learning rates, still same.
I couldn't edit dataset because of the dimensions, (input: (5000,80,60,3), output: (5000,9)), it is hard to group this mixed dataset. Confused, why?