My understand, based only on having watched Yannic Kilcher's video, is that they had in the order of 10k training cases. So not a lot. But they added a ton of

My understand, based only on having watched Yannic Kilcher's video, is that they had in the order of 10k training cases. So not a lot. But they added a ton of highly domain specific features. And since it's essentially a natural phenomenon, I would expect the signal to be relatively strong. I recommend the video, or any video from Yannic: https://youtu.be/B9PL__gVxLI