Do competitive markets remove the impact of social norms and customs on market out-comes? Or are these social forces capable of exerting a persistent influence? Many economists seem to believe that social norms and customs have, if at all, only temporary effects in competitive markets. So far...

One of the outstanding results of three decades of laboratory market research is that under rather weak conditions prices and quantities in competitive experimental markets converge to the competitive equilibrium. Yet, the design of these experiments ruled out gift exchange or reciprocity...