Here is a frequency histogram of the difference in points between the home team and visiting team at the end of regulation play. These are data from all NBA games 1997-2009. A positive number means that the home team won, a zero means that the game was tied and therefore went into overtime. Notice the massive spike at zero.
Visit the link above for a very cool video showing how this histogram changes in the waning seconds of a game.
It's not surprising that there is a spike at zero given end-of-game strategy -- a team with the opportunity to tie or lead will likely elect to take the high-percentage option -- but what surprises me is the size of the spike. I would guess that this spike would be lower in high school basketball, for example, since players are less likely to convert on end-of-game opportunities, but it would be interesting to see the two histograms side by side.
