This article is part of our Numbers Game series.
Everyone knows basketball players play worse on the second night of a back-to-back set – the second of two games played on consecutive days.
Well, one of this column's two goals is to investigate whether commonplace assumptions are statistically justified, so this topic sounds like a perfect fit. Already this season we've determined that the significance of pace is typically overstated. This week, we'll look at back-to-backs and see if the actual production matches the narrative.
Setting Up – Making a fair test
We want an apples-to-apples comparison as much as possible. For example, early this season, John Wall sat out the second night of two back-to-back sets. Tomas Satoransky averaged 31.5 minutes in those two games – he has only one game of more than 25 minutes the rest of the season. For Satoransky, the data would shows that he plays better during back-to-back sets, even though we know logically that this is misleading.
Here are some of the steps I took to minimize this kind of "noise" in my data. First, I used data from the entire 2014-15 season for this investigation (my 2015-16 database has been corrupted, and I did not have time to fix that before writing this). We want an entire season of data to ensure adequate sample size and diversity.
Second, I focused the investigation on players in the starting lineup on consecutive nights. Only players who started both games of the back-to-back set qualified. This doesn't eliminate all of the noise, but