Keras loss weights

Question

I've model with two output layers, age and gender prediction layers. I want to assign different weight values for each output layer's loss. I've the following line of code to do so.

model.compile(loss=[losses.mean_squared_error,losses.categorical_crossentropy], optimizer='sgd',loss_weights=[1,10])

My question is what is the effect of loss weights on performance of a model? How can I configure the loss weights so that the model can perform better on age prediction?

Answer 1

As stated in the book Deep Learning with Python by François Chollet:

The mean squared error (MSE) loss used for the age-regression task typically takes a value around 3–5, whereas the crossentropy loss used for the gender-classification task can be as low as 0.1. In such a situation, to balance the contribution of the different losses, you can assign a weight of 10 to the crossentropy loss and a weight of 0.25 to the MSE loss.

Answer 2

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