Your Chair emails the entire Department.  She is desperate because no-one has signed up to attend a boring but important weekend event.  If you decide you can suffer the complaints of your spouse and children for bailing on them on a Saturday, should you hit “reply” or “reply all” on your response to the Chair?

A preliminary analysis indicates that “reply all” is the best option.  First, you signal to the Department what a great public good provider you are, embellishing your image (and self-image?) as the Mahatma Gandhi-esque figure in the Department.  People will look up to you and treat you with respect.  Second, maybe you can guilt others into attending the event.  You have made a sacrifice after all and maybe they will feel compelled to as well.  So, all in all, “reply all” is looking pretty good as an optimal strategy.

But wait – you are signaling on multiple dimensions using one signal.  “Reply all” signals you have gone through the rather than vulgar and manipulative analysis in the previous paragraph.  A truly altruistic person would have signed up already without all the hot air you are blowing out of your email account.  So, you’re probably not altruistic.  In fact, you might be devious b’stard hoping to get out of serious public good provision in the future by investing one afternoon of work now.  If people make this inference, hitting “reply all” is a mistake.

With all this agonizing, research is not getting done and the web is not getting surfed.  Just randomize your choice whatever email arrives.  Sometimes you’ll look good, sometimes not so good but people will be confused – maybe you are an altruistic after all as altruists do not email strategically.  Then, you can cash in your reputation on a serious decision when it really matters not waste it on a trivial one.

(Hat Tip:  Loosely based on Stephen Morris’s paper on Political Correctness)