The question asked which UBI studies you were talking about in order to close my gap in being unable to find any. It is clear now that they don't exist, which is fine, but a bit disappointing as I would have loved to see them. There are GBI studies abound, but it seems nobody is willing to try UBI.
I hadn't gone that deeply into the studies to work out the exact thing they were testing.
The core thing that the studies have proven, I understand, is that if you guarantee people a basic living income, they don't sit around doing drugs and watching TV (or at least not for long). Which is usually the main objection from naysayers - the Theory X hypothesis that people are lazy and must be forced to do anything useful. And this is the thing that is disproved by these studies.
You seem more familiar with them, though, is that your reading too?