We use a limited information environment to assess the role of confusion in the repeated voluntary contributions game. A comparison with play in a standard version of the game suggests, that the common claim that decision errors due to confused subjects biases estimates of cooperation upwards,...

The random lottery incentive system is widely used in experimental economics to motivate subjects. This paper investigates its validity. It reports three experiments which compare responses given to decision tasks which are embedded in random lottery designs with responses in 'single choice'...