How do Graph Neural Networks Work?

Graph neural networks (GNNs) have emerged as an interesting application to a variety of problems. The most pronounced is in the field of chemistry and molecular biology. An example of the impact in this field is DeepChem, a pythonic library that makes use of GNNs. But how exactly do they work?

What are GNNs?

Typical machine learning applications will pre-process graphical representations into a vector of real values which in turn loses information regarding graph structure. GNNs are a combination of an information diffusion mechanism…