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How Derrick Rose and the Bulls were affected by rest last year

a new advanced metric shows a significant difference

David Richard-USA TODAY Sports

A consistent storyline during last season (and seasons prior) was rest given to the Bulls and how they performed as a result. Ian Levy over at Nylon Calculus spells it out:

The Bulls were outscored by 3.2 points per 100 possessions on back-to-backs, about the same as the Brooklyn Nets' scoring margin last season. One two days of rest, they outscored opponents by 9.7 points per 100 possessions, a margin that would have ranked second in the league behind the Golden State Warriors across the entire season. So at team level, two days of rest was worth about 13 points per 100 possessions in net performance.

It's an even bigger difference with Derrick Rose in particular:

[Nylon Calculus]

Earlier this year, Blog-pal Kevin Ferrigan introduced a new advanced metric dubbed "daily RAPM" (Daily Regularized Adjusted Plus Minus)  or DRE. Calculations of DRE in this case verify what many fans have noted through the "eye test" when it comes to Rose.

For some background on the statistic itself: It expands upon earlier summary statistics, such as Hollinger's PER, which combine traditional box score statistics into a single snapshot of a player's performance.

Kevin provides thorough instructions on how to calculate DRE using the free statistical software, R.  To get an idea of how DRE differs from previous summary statistics like PER, we can examine the formulas side by side:

Hollinger's PER:

PTS + 0.4 * FG – 0.7 * FGA – 0.4*(FTA – FT) + 0.7 * ORB + 0.3 * DRB + STL + 0.7 * AST + 0.7 * BLK – 0.4 * PF – TOV.

Ferrigan's DRE:

PTS + .2*TRB + 1.7*STL + .535*BLK + .5*AST – .9*FGA – .35*FTA – 1.4*TOV – .136*Minutes

We see that the difference between these metrics is the relative importance (weights) they place on each box score statistic.  For example, the formulas disagree on if a block is .7x (PER) or .535x (PER) as valuable as a point.  The advantage to Ferrigan's formula is that his weights are completely data driven, meaning he allows the numbers themselves to determine exactly how much each boxscore category should be worth, rather than making educated guesses based on intuition.

Now as to what the Bulls can do with this knowledge? Levy suggests that the difference is so stark that perhaps the Bulls should simply sit Rose more on back-to-backs. The backcourt depth poses an obviously problem with this, however. Maybe it's a result of the knee surgeries that will subside a bit this coming year, meaning a more consistently good Rose.