Should NBA Referees Call More Fouls?

By John Considine

As has been documented here previously, the Last Two Minute Reports (LTMR) produced by the NBA provide the kind of data that is difficult to get elsewhere.  These reports provide expert opinion on the decisions made by officials during the last two minutes of an NBA game.  Every decision is evaluated as correct or incorrect.  Critically, this includes non-calls, i.e. potentially foul play but deemed not to be so.  Data from the LTMRs show that just over 80% of decisions are non-calls.  This is not surprising as one could argue that there is a non-call ever second.  Below is a sample of data taken from the LTMRs.

This data is taken from a paper published in the Journal of Law and Economics.  The authors, Naci Mocan and Eric Osbourne-Christenson, examine each of the categories for racial bias and find in-group bias in the 1,068 incorrect non-calls.

What struck me about the incorrect non-calls (1,068) is that these are fouls that the referees miss.  Referees are missing around 1 in 4 fouls.  While the error rate for non-calls is 8.33% compared to 5.22% for call, there are a lot more non-calls.  What would be the implications for the game if they started calling more fouls?  Players would probably adjust and foul less.  But there would almost certainly be more stoppages.  What would be the implications for the consumers at the venue and watching the broadcast?  Would it disrupt the flow of the game and, therefore, enjoyment? It is difficult to know.