TY  - RPRT
        AU  - Abeler, Johannes
AU  - Nosenzo, Daniele
        TI  - Self-Selection into Economics Experiments Is Driven by Monetary Rewards
        PY  - 2013/Apr/
        PB  - Institute of Labor Economics (IZA)
        CY  - Bonn
        T2  - IZA Discussion Paper
        IS  - 7374
        UR  - https://www.iza.org/publications/dp7374
        AB  - Laboratory experiments have become a wide-spread tool in economic research. Yet, there is still doubt about how well the results from lab experiments generalize to other settings. In this paper, we investigate the self-selection process of potential subjects into the subject pool. We alter the recruitment email sent to first-year students, either mentioning the monetary reward associated with participation in experiments; or appealing to the importance of helping research; or both.
We find that the sign-up rate drops by two-thirds if we do not mention monetary rewards. Appealing to subjects' willingness to help research has no effect on sign-up. We then invite the so-recruited subjects to the laboratory to measure a range of preferences in incentivized experiments. We do not find any differences between the three groups. Our results show that student subjects participate in experiments foremost to earn money, and that it is therefore unlikely that this selection leads to an over-estimation of social preferences in the student population.
        KW  - social approval
KW  - other-regarding behavior
KW  - experimenter demand
KW  - laboratory experiment
KW  - social preferences
KW  - field experiment
KW  - selection bias
KW  - methodology
        ER  -