DAVID GREENE, HOST:
Nearly every worker has been in this situation. You're about to go home for the day, and the boss says, I need you to stay a little bit longer, could you just finish this extra work? Now, if you're lucky, you get paid overtime for that. But sometimes, you just have to work longer, and you get nothing. NPR's social science correspondent Shankar Vedantam brings us an account of how this plays out in a pretty unusual work setting. Hi there, Shankar.
SHANKAR VEDANTAM, BYLINE: Hi, David.