Actual data of what? The Wikipedia article talks about of different things and links to a lot of different things. https://scholar.google.com/scholar?hl=en&as_sdt=0%252C31&q=a... are plenty of papers about the Abbott districts, it's been going on for decades, and that's just about NJ, similar things have been done many places. And not even all by the government. Zuckerberg gave $100 million to Newark, Bill Gates tried a bunch of stuff, but I haven't heard much from them lately, maybe they reached the same conclusion after seeing what their money achieved.