May 2019
Intermediate to advanced
456 pages
11h 38m
English
Recently, a decades-old optimization algorithm for reinforcement learning algorithms has come back into fashion. Evolutionary strategies (ES) are much simpler than Q-learning or A2C.
Instead of training one model through backpropagation, in ES we create a population of models by adding random noise to the weights of the original model. We then let each model run in the environment and evaluate its performance. The new model is the performance-weighted average of all the models.
In the following diagram, you can see a visualization of how evolution strategies work:

Evolutionary strategy
To get a better grip ...