Self Selection Does Not Increase Other-Regarding Preferences among Adult Laboratory Subjects, but Student Subjects May Be More Self-Regarding than Adults
by Jon E. Anderson, Stephen V. Burks, Jeffrey P. Carpenter, Lorenz Götte, Karsten Maurer, Daniele Nosenzo, Ruth Potter, Kim Rocha, Aldo Rustichini
(December 2010)
revised version published as 'Self-Selection and Variations in the Laboratory Measurement of Other-Regarding Preferences Across Subject Pools: Evidence From One College Student and Two Adult Samples' in: Experimental Economics, 2013, 16 (2), 170-189; selected as best paper of 2013 by the Editors of the journal

We use a sequential prisoner's dilemma game to measure the other-regarding behavior in samples from three related populations in the upper Midwest of the United States: 100 college students, 94 non-student adults from the community surrounding the college and 1,069 adult trainee truckers in a residential training program. Both of the first two groups were recruited according to procedures commonly used in experimental economics (i.e., via e-mail and bulletin-board advertisements) and therefore subjects self-selected into the experiment. Because the structure of their training program reduced the opportunity cost of participating dramatically, 91% of the solicited trainees participated in the third group, so there was little scope for self-selection in this sample. We find no differences in the elicited other-regarding preferences between the self-selected adults and the adult trainees, suggesting that selection into this type of experiment is unlikely to bias inferences with respect to non-student adult subjects. We also test (and reject) the more specific hypothesis that approval-seeking subjects are the ones most likely to select into experiments. At the same time, we find a large difference between the self-selected students and the self-selected adults from the surrounding community: the students appear considerably less pro-social. Regression results controlling for demographic factors confirm these basic findings.
Text: See Discussion Paper No. 5389