Correct me if I'm wrong, but doesn't UBI operate on the premise that it's replacing many of the existing social programs? For example, unconditional money rather than food/housing assistance. If the participants of the study also get access to these things, doesn't that severely limit the usefulness of this study? Also, $1k/mo is pretty small. Are you just hoping to observe some behavioral changes at the margin with…
There seems to be a common bait-and-switch tactic performed by proponents of UBI, in which they mention UBI as a replacement for social programs when talking about affordability, but back away from that assertion when questioned about how to handle (for example) recipients that spend all of their UBI on drugs instead of food.
It's universal INCOME, not universal "take care of all your problems for you".