Choosing Optimal Reservoir Computers

A reservoir computer is a high dimensional dynamical system used for computation. Typically a reservoir computer is created by connecting a large number of nonlinear nodes in a network. There can be hundreds to thousands of nodes, so optimizing the structure of the reservoir computer is difficult. There are a number of conventional rules for optimizing a reservoir computer based on experience with simulations, but these rules are based on observations of a limited number of node nonlinearities. One feature of reservoir computers is that they may be built from connecting together analog nodes such as lasers, quantum dots, memristors, or other devices. There is a great range of possible nonlinear functions describing these nodes, so design rules beyond the conventional wisdom are required.

 

One conventional design rule that I show is not always true is that reservoir computers function best at the edge of stability, or the “edge of chaos”. There are dynamical reasons why this rule is not always true. I will also show some other statistics that are useful for improving reservoir computer performance, such as symmetry and the strength of connections between nodes.