Instead of searching through every hyperparameterizations in a pre-defined set, as is the case with a grid search, in a random search we sample from a distribution of possibilities by assuming each hyperparameter to be a random variable. Before we go through the process in depth, it will be helpful to briefly review what random variables are and what we mean by a distribution.
Random Variables and Their Distributions
A random variable is non-constant (its value can change) and its variability can be described in terms of distribution. There are many different types of distributions, but each falls into one of two broad categories: discrete and continuous. We use discrete distributions to describe random variables whose values can take only whole numbers, such as counts.
An example is the count of visitors to a theme park in a day, or the number of attempted shots it takes a golfer to get a hole-in-one.
We use continuous distributions to describe...