Terminology for games with incomplete information and no prior beliefs Can anyone please tell me what is the term used for games with incomplete information and there are no prior beliefs about other players' private information. 

For example, let $ v_i(a_i,\theta_i) $ be the utility function of the player $ i $ and $ a_i $ be decided for each player some how. $ \theta_i $ be the private information for player $ i $. Player $ i $ has no belief (no knowledge of probability distribution) about others' private information except that it is a real number. Few authors call such games to be pre-Bayesian games. But there seems to be no standard. It would be great if any one can let me know this. Thanks!
Uncertainty in the absence of a prior distribution is sometimes called Knightian Uncertainty in economics. There are a couple of recent papers studying how to deal with knightian uncertainty in mechanism design. See for example:

The Knightian Truthfulness of Classical Mechanisms

Knightian Auctions