How past experiences shape decisions about future behaviors: A large-scale natural field experiment with volunteer crisis counselors

We investigated how the content and order of past experiences shape decisions about future behaviors by volunteer crisis counselors, who were repeatedly and randomly assigned to perform harder prosocial behaviors (suicide conversations) or easier prosocial behaviors (non-suicide conversations). Content of past experiences mattered: Harder behaviors encouraged quitting. Surprisingly, order of past experiences mattered up to 99 times more than content: Harder behaviors caused disproportionately more quitting if they arrived in long “streaks” or at the “end.” These “streak”/“end” effects violate fundamental principles of rational decision making such as time neutrality, revealing for the first time that time-neutrality violations have persistent, disproportionate, and powerful impacts on real-world behavior outside of laboratory/clinical settings. Our results suggest a “reordering intervention” would double prosocial behavior, saving lives.