Bidding above the risk-neutral Nash Equilibrium in first price sealed bid auctions has traditionally been ascribed to risk aversion. Recent studies, however, offer other explanations and argue that risk aversion plays no or only a minor role. So far, no study has shown a causal relationship...

Although a number of theoretical studies explain empirical puzzles in finance with ambiguity aversion, it is not a given that individual ambiguity attitudes survive in markets. In fact, despite ample evidence of ambiguity aversion in individual decision making, most studies find no or only...