Back in like 2001 I tried to build a psych instrument that had better than random chance of predicting whether someone would one-box or two-box in a specific, grounded and controlled Newcombe's Paradox situation - and that retained its calibration even when the the situation was modified into its probabilistic form and the actual measured calibration was honestly reported to the participants.

This sounds very interesting, so I second Blueberry's questions.

(Edit - beaten by Eliezer - I guess I third them.)