The Economic Origins of Government
利用伊拉克南部河流改道作为自然实验，检验政府起源的合作理论与掠夺理论，发现河流改道促使国家形成、运河修建和贡赋支付，支持合作理论。
We test between cooperative and extractive theories of the origins of government. We use river shifts in southern Iraq as a natural experiment, in a new archeological panel dataset. A shift away creates a local demand for a government to coordinate because private river irrigation needs to be replaced with public canals. It disincentivizes local extraction as land is no longer productive without irrigation. Consistent with a cooperative theory of government, a river shift away led to state formation, canal construction, and the payment of tribute. We argue that the first governments coordinated between extended households which implemented public good provision.