Many consumption prices are highly volatile. It would certainly overburden our cognitive system to fully adjust to all these changes. Households therefore often rely on simple heuristics when deciding what to consume, e.g. in the form of a constant budget share for a specific consumption...

Experimental studies have shown that trust and reciprocity are effective in increasing efficiency when complete contracting is infeasible. One example is the study by Berg et al. (1995) of the investment game. In this game the person who receives the investment is the one who may reward the...