External validity in economic experiments: can students be used to approximate the behavior of farmers?
Final Report Abstract
Experiments enable to study decision-making behavior under controlled conditions. Students are often used for this purpose due to their low opportunity costs (i.e. low costs in conducting the experiment) and easy recruitability. However, for many research questions, students are an untypical population. For example, farmers are on average older, have more work experience, and have more income than students. Against this background, the question arises as to what extent the experimental behavior of farmers can be approximated by students. In practice, inferences from students to other populations are sometimes made hastily. However, there are only a few systematic investigations. This project addresses this question with the help of two experimental studies. In the first study, 150 agricultural students and 150 farmers were compared on 6 personality traits (risk attitude, time preferences, positive and negative reciprocity, altruism, and trust) considering 3 monetary incentive levels. In other words, there are 36 sub-experiments. The heterogeneous results suggest that scientific inference from agricultural students to farmers should be made with caution. In the second study, 200 students and 200 farmers were recruited to investigate the influence of thinking about future consequences of climate change on risk preferences and cooperation behavior. Farmers showed a higher willingness to take risks (in the form of a greater willingness to invest in risky assets) as a result of remembering climate change; the effect cannot be found with students. Cooperative behavior remained largely unaffected in both populations. Emotions were considered as possible drivers of behavior. Moreover, methodological aspects, such as replications, pre-registration, and power analysis were examined in the project. Furthermore, the trend to conduct web-based studies with the “general population” is considered.
Publications
- (2020): Inference in economic experiments. Economics: The Open-Access, Open-Assessment E-Journal 14(2020-7): 1-14
Hirschauer, N., Grüner, S., Mußhoff, O., Becker, C.
(See online at https://doi.org/10.5018/economics-ejournal.ja.2020-7) - (2020): Sample Size Calculation in Economic Experiments. Journal of Economics and Statistics 240(6): 791-823
Grüner, S.
(See online at https://doi.org/10.1515/jbnst-2019-0020) - (2021): Consumers’ willingness to pay for plants protected by beneficial insects—Evidence from two stated-choice experiments with different subject pools. Food Policy 102: 102100
Lehberger, M., Grüner, S.
(See online at https://doi.org/10.1016/j.foodpol.2021.102100) - (2021): Rethinking How Risk Aversion and Impatience Are Linked with Cognitive Ability: Experimental Findings from Agricultural Students and Farmers. Journal of Environmental Economics and Policy
Gruener, S.
(See online at https://doi.org/10.1080/21606544.2021.1966516) - (2022): Experienced survey participants, biased responses? – The example of cognitive reflection. Applied Economics Letters
Grüner, S., Hirschauer, N.
(See online at https://doi.org/10.1080/13504851.2022.2107982) - (2022): How (un-)informative are experiments with students for other social groups? – A study of agricultural students and farmers. Australian Journal of Agricultural and Resource Economics 66(3): 471-504
Grüner, S., Lehberger, M., Mußhoff, O., Hirschauer, N.
(See online at https://doi.org/10.1111/1467-8489.12485) - (2022): The economic psychology of climate change: An experimental study on risk uncertainty and cooperation. OSF Preprints
Grüner, S.
(See online at https://doi.org/10.31219/osf.io/jq57n)