) and therefore subjects self-selected into the experiment. Because the structure of their training program reduced the …-selected adults and the adult trainees, suggesting that selection into this type of experiment is unlikely to bias inferences with … experiment ; field experiment ; other-regarding behavior ; social preferences ; truckload ; trucker …

and therefore subjects self-selected into the experiment. Because the structure of their training program reduced the …-selected adults and the adult trainees, suggesting that selection into this type of experiment is unlikely to bias inferences with …-selected adults: the students appear considerably less pro-social. -- methodology ; selection bias ; laboratory experiment ; field …