This paper presents data from experiments with a linear voluntary contributions mechanism for public goods conducted in Japan, the Netherlands, Spain and the USA. The same experimental design was used in the four countries. Our 'contribution function' design allows us to obtain a more complete...

Bertrand competition under decreasing returns involves a wide interval of pure strategy equilibrium prices. We first present results of experiments in which two, three and four identical firms repeatedly interact in this environment. Less collusion with more firms leads to lower average prices....