I have an imbalanced dataset for a classification task. There are 7 classes for output.
Each proportion is around 10%, 3%, 6%, 39%, 16%, 6%, 20%.
I use cross-entropy loss and I have tired weighted loss as [2, 8.5, 3.5, 4, 1.5, 4, 8], but it does not help.
The loss curve is clearly overfitting. I could achieve around 99% accuracy for training but, get an unchanged 70% for validation.
What else really helpful could I do?