This paper demonstrates theoretically and experimentally that in first-price auctions overbidding with respect to the risk neutral Nash equilibrium might be driven from anticipated loser regret (felt when bidders lose at an affordable price). Different information structures are created to elicit regret: bidders know they will learn the winning bid if they lose (loser regret condition); or the second-highest bid if they win (winner regret condition); or they will receive no feedback regarding the other bids. Bidders in loser regret condition anticipated regret and significantly overbid. However, bidders in the winner regret condition did not anticipate regret.

The standard revealed preference argument relies on an implicit assumption that a decision maker considers all feasible alternatives. The marketing and psychology literatures, however, provide well-established evidence that consumers do not consider all brands in a given market before making a purchase (Limited Attention). In this paper, we illustrate how one can deduce both the decision maker's preference and the alternatives to which she pays attention and inattention from the observed behavior. We illustrate how seemingly compelling welfare judgments without specifying the underlying choice procedure are misleading. Further, we provide a choice theoretical foundation for maximizing a single preference relation under limited attention.

In Brock, Lange, and Ozbay (2013), we experimentally investigate social preferences under risk. One of our conclusions is that a social preference model incorporating both ex ante and ex post fairness concerns may best describe behavior. Krawczyk and Le Lec (2016 ) argue that ex ante comparisons alone may account for our data. We address their points in this reply.

We study if and how social preferences extend to risky environments. We provide experimental evidence from different versions of dictator games with risky outcomes and establish that preferences that are exclusively based on ex post or on ex ante comparisons cannot generate the observed behavioral patterns. The more money decision-makers transfer in the standard dictator game, the more likely they are to equalize payoff chances under risk. Risk to the recipient does, however, generally decrease the transferred amount. Ultimately, a utility function with a combination of ex post and ex ante fairness concerns may best describe behavior.