If you don’t see it in the upcoming FIBA World Championship, you’ll no doubt see it countless times during the NBA and college basketball season: Your team is up by three points in the final seconds, the bad guys have the ball, and going into that last possession, the question is whether or not your team should foul.
It comes down to this: Do you foul and put your opponent on the line for two shots (where they can’t possibly tie the game), or let them take a lower-percentage triple and bank on a miss?
Each coach has their own philosophy. Phil Jackson, for example, almost never chooses to foul, whereas some coaches always tell their players to foul. Often it’s circumstantial: Does the other team have a hot three-point shooter? Do they have a notorious closer like Kobe? Are your defenders good enough to put up resistance but also poised enough to not foul while somebody is taking a three?
A recent study by John Ezekowitz posted on the Harvard Sports Analysis site tried to answer the big question, with a focus on college basketball. Citing 443 examples of instances where teams had a chance to tie with a three in the final seconds, Ezekowitz writes:
Of the 52 teams that committed a foul, six lost the game for a winning percentage of 88.46%. Of the 391 teams that did not foul, 33 lost the game for a winning percentage of 91.56%. Both a two sample t-test of proportion and a Chi-squared test fail to reject the null hypothesis that there is a difference in winning percentage between the two strategies. In this sample, teams that did not foul won slightly more often. For the less statistically inclined, this means that there is no significant difference between the two strategies.
In other words, there’s no statistical evidence that one strategy is clearly better than the other. So we’re back to square one: It’s up to the coach’s preference and comfort level with his team.
What would your strategy be if your team is up three in the final seconds and the other team has the ball?