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Why do we need epochs?

In courses there is nothing about epochs, but in practice they are everywhere used. Why do we need them if the optimizer finds the best weight in one pass. Why does the model improve?

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Slava Mulyukin Avatar asked Mar 10 '17 10:03

Slava Mulyukin


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1 Answers

Generally whenever you want to optimize you use gradient descent. Gradient descent has a parameter called learning rate. In one iteration alone you can not guarantee that the gradient descent algorithm would converge to a local minima with the specified learning rate. That is the reason why you iterate again for the gradient descent to converge better.

Its also a good practice to change learning rates per epoch by observing the learning curves for better convergence.

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Sarthak Avatar answered Sep 21 '22 23:09

Sarthak