The power of big data—why so many corporations and government agencies and political pollsters and baseball teams are after it—is that it can reveal things we might otherwise not see. But statistics alone can’t do that. We need to transform those statistics into stories. One artist doing that is Brian Foo, aka the Data Driven DJ. He takes large data sets and turns them into music. His first song, “Two Trains,” amplifies a dire but often ignored truth about our country: income inequality.