Quote:
Originally Posted by Scoobay
nice stat!
what is defensive rating calculated based off of?
is this considered a reliable metric?
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Per basketball-reference.com
Defensive Rating estimates how many points the player allowed per 100 possessions he individually faced while on the court.
The core of the Defensive Rating calculation is the concept of the individual Defensive Stop. Stops take into account the instances of a player ending an opposing possession that are tracked in the boxscore (blocks, steals, and defensive rebounds), in addition to an estimate for the number of forced turnovers and forced misses by the player which aren't captured by steals and blocks.
The formula for Stops is:
Stops = Stops1 + Stops2
where:
Stops1 = STL + BLK * FMwt * (1 - 1.07 * DOR%) + DRB * (1 - FMwt)
FMwt = (DFG% * (1 - DOR%)) / (DFG% * (1 - DOR%) + (1 - DFG%) * DOR%)
DOR% = Opponent_ORB / (Opponent_ORB + Team_DRB)
DFG% = Opponent_FGM / Opponent_FGA
Stops2 = (((Opponent_FGA - Opponent_FGM - Team_BLK) / Team_MP) * FMwt * (1 - 1.07 * DOR%) + ((Opponent_TOV - Team_STL) / Team_MP)) * MP + (PF / Team_PF) * 0.4 * Opponent_FTA * (1 - (Opponent_FTM / Opponent_FTA))^2
Also necessary is the calculation of Stop%, which is the rate at which a player forces a defensive stop as a percentage of individual possessions faced (essentially the inverse of Floor%, but for defenders):
Stop% = (Stops * Opponent_MP) / (Team_Possessions * MP)
With those numbers in hand, individual Defensive Rating can be computed:
DRtg = Team_Defensive_Rating + 0.2 * (100 * D_Pts_per_ScPoss * (1 - Stop%) - Team_Defensive_Rating)
where:
Team_Defensive_Rating = 100 * (Opponent_PTS / Team_Possessions)
D_Pts_per_ScPoss = Opponent_PTS / (Opponent_FGM + (1 - (1 - (Opponent_FTM / Opponent_FTA))^2) * Opponent_FTA*0.4)
As far as I know, it's a solid stat. Like any other stat, it's not at all definitive by itself, but as part of a bigger picture, it's reliable. So while I don't think we can take this to mean that Luka is now the best defensive PG in the league, we can take it to mean that his defense has improved by a lot. No doubt this is due to a combination of his improved conditioning, and an an overall increased focus on defense coming from the coaching.
I don't think he'll ever be an elite defender, but you can see it with your eyes that he's more than serviceable on that end. He's extremely big and strong for a point guard, and his basketball IQ is through the roof.