With Reto Jegen

Survey paper on the crowding out of intrinsic motivation From the conclusion of the Annals of Economics and Statistics 2001 paper: "Many scholars have accepted the theoretical possibility of crowding effects, i. e. that an external intervention via monetary incentives or punishments may undermine (and under different indentifiable conditions strengthen) intrinsic motivation. But many of them have een critical about the empirical relevance of the crowding effects. This paper shows that this skepticism is unwarranted and that there exists indeed compelling empirical evidence for the existence of crowding out and crowding in. This conclusion is based on circumstantial evidence, laboratory evidence by both psychologists and economists as well as field evidence by econometric studies."

From the abstract of the 2001 Journal of Economic Surveys paper: "As of today, the theoretical possibility of motivation crowding has been the main subject of discussion among economists. This study demonstrates that the effect is also of empirical relevance. There exist a large number of studies, offering empirical evidence in support of the existence of crowding–out and crowding–in. The study is based on circumstantial evidence, laboratory studies by both psychologists and economists, as well as field research by econometric studies. "