Decision markets are markets where speculators set prices that estimate the consequences of a decision.

… writes Robin Hanson (who is into prediction markets since the late 80s, and who is the smartest scholar on this topic).

I would call that “decision-aid markets“, then. And I would have the term “decision markets” define the strongest form of this tool, envisioned originally by Robin Hanson (PDF file) —that is, when the execution of the market-generated decision is compulsory.