What is a soft maximum?

What is a soft maximum?

The soft maximum approximates the hard maximum and is a convex function just like the hard maximum. But the soft maximum is smooth. It has no sudden changes in direction and is infinitely differentiable. These properties make it useful in convex optimization algorithms.

What is a smooth approximation?

In mathematics, a smooth maximum of an indexed family x1., xn of numbers is a smooth approximation to the maximum function meaning a parametric family of functions such that for every α, the function is smooth, and the family converges to the maximum function as . The concept of smooth minimum is similarly defined.

Is maximum differentiable?

max is differentiable with respect to the values, not the indices.

What is Nonsmooth optimization?

Nonsmooth optimization (NSO) refers to the general problem of minimizing (or maximizing) functions that are typically not differentiable at their minimizers (maximizers). Note that no differentiability or convexity assumptions are made. The simplest example of nonsmooth function is the absolute-value function on reals.

Why is Max not differentiable?

No, h(x)=max(cosx,sinx) is not differentiable at x=π4+kπ. This is because when you switch from f to g, the slopes have no reason to be equal.

Is Torch Argmax differentiable?

As alvas noted in the comments, argmax is not differentiable. However, once you compute it and assign each datapoint to a cluster, the derivative of loss with respect to the location of these clusters is well-defined.

How is the softmax function different from the maximum function?

Intuitively, the softmax function is a “soft” version of the maximum function. Instead of just selecting one maximal element, softmax breaks the vector up into parts of a whole (1.0) with the maximal input element getting a proportionally larger chunk, but the other elements getting some of it as well [1].

What’s the difference between Softmax and arg max?

In some fields, the base is fixed, corresponding to a fixed scale, while in others the parameter β is varied. The name “softmax” is misleading; the function is not a smooth maximum (a smooth approximation to the maximum function), but is rather a smooth approximation to the arg max function: the function whose value is which index has the maximum.

When was the softmax function first formalized?

The softmax function was used in statistical mechanics as the Boltzmann distribution in the foundational paper Boltzmann (1868), formalized and popularized in the influential textbook Gibbs (1902).

Which is the most general Jacobian matrix for softmax?

Therefore, when we try to find the derivative of the softmax function, we talk about a Jacobian matrix, which is the matrix of all first-order partial derivatives of a vector-valued function. Since softmax is a RK → RK mapping function, the most general Jacobian matrix for it is: