# What is decay in RMSprop?

## What is decay in RMSprop?

Learning rate decay is a mechanism generally applied independently of the chosen optimizer. Keras simply builds this mechanism into the RMSProp optimizer for convenience (as does it with other optimizers like SGD and Adam which all have the same “decay” parameter).

### What is RMSprop in keras?

Optimizer that implements the RMSprop algorithm. The gist of RMSprop is to: Maintain a moving (discounted) average of the square of gradients. Divide the gradient by the root of this average.

#### How is RMSprop defined?

What is RMSprop? RMSprop is a gradient based optimization technique used in training neural networks. It was proposed by the father of back-propagation, Geoffrey Hinton.

Does Adam need learning rate decay?

Yes, absolutely. From my own experience, it’s very useful to Adam with learning rate decay. Without decay, you have to set a very small learning rate so the loss won’t begin to diverge after decrease to a point.

Adam is a replacement optimization algorithm for stochastic gradient descent for training deep learning models. Adam combines the best properties of the AdaGrad and RMSProp algorithms to provide an optimization algorithm that can handle sparse gradients on noisy problems.

## What does Adam Optimizer do?

### What is RMSprop used for?

RMSProp is a very effective extension of gradient descent and is one of the preferred approaches generally used to fit deep learning neural networks. Empirically, RMSProp has been shown to be an effective and practical optimization algorithm for deep neural networks.

#### What is weight decay Adam?

Optimal weight decay is a function (among other things) of the total number of batch passes/weight updates. Our empirical analysis of Adam suggests that the longer the runtime/number of batch passes to be performed, the smaller the optimal weight decay.

What is decay rate in Adam?

Further, learning rate decay can also be used with Adam. The paper uses a decay rate alpha = alpha/sqrt(t) updted each epoch (t) for the logistic regression demonstration. Keras: lr=0.001, beta_1=0.9, beta_2=0.999, epsilon=1e-08, decay=0.0.