## What will be the KL divergence between P and Q?

It uses the KL divergence to calculate a normalized score that is symmetrical. This means that the divergence of P from Q is the same as Q from P, or stated formally: JS(P || Q) == JS(Q || P)

## What is KL divergence loss?

So, KL divergence in simple term is a measure of how two probability distributions (say ‘p’ and ‘q’) are different from each other. So this is exactly what we care about while calculating the loss function.

Where can I use KL divergence?

The Kullback-Leibler divergence is widely used in variational inference, where an optimization problem is constructed that aims at minimizing the KL-divergence between the intractable target distribution P and a sought element Q from a class of tractable distributions.

### Why do we use KL divergence?

As we’ve seen, we can use KL divergence to minimize how much information loss we have when approximating a distribution. Combining KL divergence with neural networks allows us to learn very complex approximating distribution for our data.

### Is KL divergence differentiable?

Smaller KL Divergence values indicate more similar distributions and, since this loss function is differentiable, we can use gradient descent to minimize the KL divergence between network outputs and some target distribution.

What does large KL divergence mean?

“…the K-L divergence represents the number of extra bits necessary to code a source whose symbols were drawn from the distribution P, given that the coder was designed for a source whose symbols were drawn from Q.” Quora. and. “…it is the amount of information lost when Q is used to approximate P.” Wikipedia.

#### Is the KL divergence symmetric?

Although the KL divergence measures the “distance” between two distri- butions, it is not a distance measure. This is because that the KL divergence is not a metric measure. It is not symmetric: the KL from p(x) to q(x) is generally not the same as the KL from q(x) to p(x).

#### Is KL divergence negative?

The KL divergence is non-negative.