Results from an experiment comparing monetary and non-monetary punishment (sanctions) in a voluntary contribution mechanism (VCM) public good game are reported. Monetary punishment (MP) increased contribution rates more for teams than for individuals, with teams targeting three times as much punishment to below average contributors compared to individuals. Non-monetary punishment (NMP) increased contribution rates for individuals but had no significant effect for teams. Absent punishment, teams had significantly greater reductions in end game contributions than individuals.
(joint with John Kagel and Christina Gore)