[mikkom]

Unless there are people in the "crowd" who work in machine learning / data mining in totally different sector (let's say genomics/biostatistics as this is the example in the article) but have no access to the hedge fund world.

The "crowd" could very well have a long list of very intelligent people who are "experts" in some other sector and who have fresh insights and want to get some anonymous extra income on top of their salary.

This said, I think their compensation seems really low.