Tensorflow 1.x backend: add dropout to DeepONet

[vl-dud]

Now DeepONet supports dropout technique.

[lululxvi]

Do you use dropbox to prevent overfitting?

[vl-dud]

Do you use dropbox to prevent overfitting?

Yes, I'm using dropout_rate right now during hyperparameter tuning. I'll write how useful it is in my case.

[lululxvi]

I am curious how useful it is. In general, I found dropout is not that useful, and L1/L2 regularization seems good enough.

[vl-dud]

I am curious how useful it is. In general, I found dropout is not that useful, and L1/L2 regularization seems good enough.

Hyperparameter tuning showed that in my case neither dropout nor regularization is required. However I will use dropout anyway for UQ.

[lululxvi]

Yes, dropout is useful for UQ. How do you implement DeepONet UQ?

[vl-dud]

I just run model.predict many times to get the final prediction with CI:

def predict_with_uncertainty(model, x, trial_num=100):
    predictions = []
    for _ in range(trial_num):
        predictions.append(model.predict(x))
    return np.mean(predictions, axis=0), np.std(predictions, axis=0)

[lululxvi]

In fact, we have this callback https://deepxde.readthedocs.io/en/latest/modules/deepxde.html#deepxde.callbacks.DropoutUncertainty . Does this work for your case?

[vl-dud]

Yes, I used DropoutUncertainty. The above code snippet is more convenient in my case, since I use it with already trained models.
In addition, it allows you to set trial_num, which is a constant in DropoutUncertainty.