Most likely your model is predicting the majority class only, so I guess it’s predicting the  False class. You can check it by printing the unique predictions for the datasets.

You mean, take the predictions and see their probability distributions?

You could use  nn.BCEWithLogitsLoss , remove the  sigmoid , and set the  pos_weight  as  number_negative_samples / number_positive_samples . If that doesn’t work, try to use  WeightedRandomSampler  as described here 1.

I’ll do it and let you know

Also, note that the accuracy can be misleading for an imbalanced dataset as described in the Accuracy paradox.

I’ll ckeck out both links
Thanks @ptrblck, best regards