Hi guys, my first week here and my first post!

Though initially I thought I understood, I’m been struggling to see the relationship between loss and accuracy for the validation set. Saw a few similar topics in the forums, but no answer has helped me so far.

I would expect the see the loss to go down as the accuracy ramps up, however, I’m seeing scenarios where does is not the case (seeing scenarios where it’s as I expect too [2]). For example:

[1]

*Epoch 1/5*

*23000/23000 [==============================] - 649s - loss: 0.3727 - acc: 0.9763 - val_loss: 0.2350 - val_acc: 0.9845*

*Epoch 2/5*

*23000/23000 [==============================] - 651s - loss: 0.3576 - acc: 0.9774 - val_loss: 0.2279 - val_acc: 0.9850*

*Epoch 3/5*

*23000/23000 [==============================] - 652s - loss: 0.3867 - acc: 0.9754 - val_loss: 0.2260 - val_acc: 0.9855*

*Epoch 4/5*

*23000/23000 [==============================] - 652s - loss: 0.3630 - acc: 0.9770 - val_loss: 0.2225 - val_acc: 0.9860*

*Epoch 5/5*

*23000/23000 [==============================] - 651s - loss: 0.3688 - acc: 0.9766 - val_loss: 0.2177 - val_acc: 0.9860*

[2]

*Epoch 1/1*

*60000/60000 [==============================] - 19s - loss: 0.1123 - acc: 0.9654 - val_loss: 0.0358 - val_acc: 0.9869*

For example, submiting [1] to Kaddle for the Cats and Dogs problem, gave me a 0.10243 score. I did take into account chipping (used 0.5 and .95 and other parameters), so I don’t understand why that score, when the validation accuracy is 0.9766.

At some point, I suspected my validation set was not good, so I picked another random sample, also tried making it bigger. But I ended up with similar results.

I think my model might be being overly confident, and being penalized by the loss function, but I don’t understand why that happens, or how to fix it.

Thanks in advance for any help!