Formula To Determine If You Should Leave A Sporting Event Early

As a fairly new dad, this was my immediate reaction to yesterday's NFC Championship game: https://twitter.com/rafaan/status/556994864899182593 EDIT (thanks Joshua): ...and where 'epicness of potential ending' > 0.
Alt-Text: You may leave early in the event of a fire, riot, or Justin Bieber halftime show.