We show that extrinsic or non-fundamental uncertainty influences markets in a controlled environment. This work provides the first direct evidence of sunspot equilibria. These equilibria require a common understanding of the semantics of the sunspot variable, and they appear to be sensitive to...

We explore the effect of fixed versus dynamic group membership on public good provision. In a novel experimental design, we modify the traditional voluntary contribution mechanism (VCM) by periodically replacing old members of a group with new members over time. Under this dynamic, overlapping...