Does Anonymity Affect the Willingness To Accept and Willingness To Pay Gap?*

Conventional value-elicitation experiments often find subjects provide higher valuations for items they posses than for identical items they may acquire. Plott and Zeiler (2005) find no difference in elicited valuations after implementing procedures that provide for anonymity and experience with the second-price mechanism. This paper investigates whether anonymity is a necessary for their result. Employing a similar design to theirs, we find their general result holds in conditions both with and without anonymity. Contrary to predictions of one theory—which suggest social pressures may cause differences in subject valuations—anonymous and non-anonymous subjects have nearly identical valuations. As a robustness check, we note the subjects across conditions give significantly different amounts in a dictator game, suggesting they were aware of the conditions of anonymity and sensitive to the accompanying social pressures. Together, these findings strongly suggest subject familiarity with elicitation mechanisms, not anonymity, is responsible for the variability in results across value-elicitation experiments. As an application to experimental design methodology, there appears to be little need to impose anonymity in the laboratory when using second-price mechanisms as we see negligible differences in elicited values with and without anonymity