We test an assortative mechanism whereby groups are formed endogenously, through the use of voting. Once formed, groups play a public-goods game, where the social value of an incremental contribution to the group account increases with the size of the group. Societies of nine people are...

We test a mechanism whereby groups are formed voluntarily, through the use of voting. These groups play a public-goods game, where efficiency increases with group size (up to a limit, in one treatment). It is feasible to exclude group members, to exit one's group, or to form larger groups...

The ‘ratchet effect’ refers to a situation where a principal uses private information that is revealed by an agent’s early actions to the agent’s later disadvantage, in a context where binding multi-period contracts are not enforceable. In a simple, context-rich environment, we...

The 'ratchet effect' refers to a situation where a principal uses private information that is revealed by an agent's early actions to the agent's later disadvantage, in a context where binding multi-period contracts are not enforceable. In a simple, context-rich environment, we experimentally...

The 'ratchet effect' refers to a situation where a principal uses private information that is revealed by an agent's early actions to the agent's later disadvantage, in a context where binding multi-period contracts are not enforceable. In a simple, context-rich environment, we experimentally...

The 'ratchet effect' refers to a situation where a principal uses private information that is revealed by an agent's early actions to the agent's later disadvantage, in a context where binding multi-period contracts are not enforceable. In a simple, context-rich environment, we experimentally...