The importance of intrinsic and extrinsic motivation for measuring IQ
We disentangle these two elements empirically using data from a laboratory experiment. The main findings is that both intrinsic (questions that people like to work on) and extrinsic motivation (incentive payments) increase time investments and as a result performance. The presence of incentive payments seems to be more important than the size of the reward. Intrinsic and extrinsic motivation turn out to be complements.