Social interactions and the influence of “extremists”

•We study whether face-to-face group deliberation changes other-regarding preferences, particularly when individuals have to make their decisions alone afterwards.•We use a structural choice-revealed preference approach to measure each individual’s other-regarding preferences in a modified dictator game.•We examine heterogeneity in preferences and changes in these preferences before and after group deliberation.•We find that social interactions do indeed change individual preferences, even after they have left the group. In particularly, preferences of individuals in the same group become more homogenous after interactions.•We also find that students are more susceptible to social influence of individuals with extremely selfish preference (the “extremists” in our title) compared to non-students.