@TechReport{iza:izadps:dp5774,
            	author={Gächter, Simon and Kessler, Esther and Königstein, Manfred},
            	title={The Roles of Incentives and Voluntary Cooperation for Contractual Compliance},
            	year={2011},
	month={Jun},
            	institution={Institute of Labor Economics (IZA)},
            	address={Bonn},
            	type={IZA Discussion Paper},
            	number={5774},
            	url={https://www.iza.org/publications/dp5774},
	abstract={Efficiency under contractual incompleteness often requires voluntary cooperation in situations where self-regarding incentives for contractual compliance are present as well. Here we provide a comprehensive experimental analysis based on the gift-exchange game of how explicit and implicit incentives affect cooperation. We first show that there is substantial cooperation under non-incentive compatible contracts. Incentive-compatible contracts induce best-reply effort and crowd out any voluntary cooperation. Further experiments show that this result is robust to two important variables: experiencing Trust contracts without any incentives and implicit incentives coming from repeated interaction. Implicit incentives have a strong positive effect on effort only under non-incentive compatible contracts.},
	keywords={repeated games;implicit incentives;explicit incentives;incomplete contracts;gift-exchange experiments;principal-agent games;separability;experiments},
            }