Ambiguity, asset illiquidity, and price variability

Abstract

I develop a sequential trading model with ambiguity-averse market makers and provide a theoretical explanation to the historical coincidence of ambiguous events, asset illiquidity, and price variability. My model implies that the bid-ask spread of an asset contains an additive component of ambiguity premium. As a result, higher ambiguity generally leads to lower asset liquidity. More interestingly, asset prices are variable under particular conditions: specifically, only mixed-strategy equilibria exist, such that market makers probabilistically set multiple prices. Further analysis confirms that, compared with risk, ambiguity plays a unique role in explaining price variability.