The standard state-spaces of asymmetric information preclude non-trivial forms of unawareness (Modica and Rustichini, 1994, Dekel, Lipman and Rustichini, 1998). We introduce a generalized state-space model that allows for non-trivial unawareness among several individuals, and which satisfies...

We present a non-technical account of ambiguity in strategic games and show how it may be applied to economics and social sciences. Optimistic and pessimistic responses to ambiguity are formally modelled. We show that pessimism has the effect of increasing (decreasing) equilibrium prices under...

It is known that there are uncoupled learning heuristics leading to Nash equilibrium in all finite games. Why should players use such learning heuristics and where could they come from? We show that there is no uncoupled learning heuristic leading to Nash equilibrium in all finite games that a...

One fundamental assumption often made in the literature on unawareness is that risk preferences are invariant to changes of awareness. We study how exposure to unawareness affects choices under risk. Participants in our experiment choose repeatedly between varying sure outcomes and a lottery in...

It is known that there are uncoupled learning heuristics leading to Nash equilibrium in all finite games. Why should players use such learning heuristics and where could they come from? We show that there is no uncoupled learning heuristic leading to Nash equilibrium in all finite games that a...

We study the informational effectiveness of electoral campaigns. Voters may not think about all political issues and have incomplete information with regard to political positions of candidates. Nevertheless, we show that if candidates are allowed to microtarget voters with messages then...

We present a new solution concept for strategic games called comprehensive rationalizability that embodies "common cautious belief in rationality" based on a sound epistemic characterization in a universal type space. It refines rationalizability, but it neither refines nor is refined by...

We extend Kuhn's Theorem to extensive games with unawareness. This extension is not entirely obvious: First, extensive games with non-trivial unawareness involve a forest of partially ordered game trees rather than just one game tree. An information set at a history in one tree may consist of...

We study experimentally persuasion games in which a sender (e.g., a seller) with private information provides verifiable but potentially vague information (e.g., about the quality of a product) to a receiver (e.g., a buyer). Various theoretical solution concepts such as sequential equilibrium or...

The standard state-spaces of asymmetric information preclude non- trivial forms of unawareness (Dekel, Lipman and Rustichini, 1998). We introduce a generalized state-space model that allows for non-trivial unawareness among several individuals, and which satisfies strong properties of knowledge...