This paper provides a unified theory of the economic and demographic transition. Individuals make optimal decisions about fertility, education of their children and the type and intensity of the investments in their own education. These decisions are affected by different dimensions of mortality...

Empirical studies of the principal-agent relationship find that extrinsic incentives work in many instances, linking rewards to performance increases effort, but that they can also backfire, reducing effort. Intrinsic motivation, the internal drive to work to master a skill or to improve one's...