We elicit human conditional punishment types by conducting experiments. We find that their punishment decisions to an individual are on average significantly positively proportional to other members’ punishment decisions to that individual.

I study a single-agent dynamic purchase problem by using a Gul and Pesendorfer’s [Gul, F., Pesendorfer, W., 2007. Harmful addiction. Review of Economic Studies 74 (1), 147–172] dynamic preference: extreme self-control cannot be sustained and leads to addiction. This type of agent exhibits...