Assist Quality, the hidden perspective, Lin and Rockets

Assist Quality, the hidden perspective, Lin and Rockets

2012 SportVU released an article on “Potential Assist Locations”, which shows Lin’s potential assists contain 36% at rim opportunities, the most among PG.







As you can see from the diagram, such passes make big difference for shots at rim, not so much for long 2 and 3. However we knew that most 3pt shots were only taking when you have a open look.

Back then, there is no statistics publicly available for further quantitative analysis. Until this season NBA.com introduces SportVU passing tracking statistics.

2013-2014 season until ASB, among 100 most assisters, the median Assist Efficiency (AE) is 1.20.

Assist Efficiency (AE) = [Point created by assist per game] / [Assist Opportunities per game] (AO)

Assist Opportunity means passes result in shots, result in shooting foul not included.

Lin’s AE = 10.9/7.9 = 1.38, is 3rd among league, 1st among PGs, only 5 PGs ranked among TOP25 AE. ( Parson 1.28 Harden 1.17 Beverley 1.17)

No doubt Lin has high AE because of close to rim passes, which comes at a price: turnovers, was it worth the effort?

If we adjust Lin’s AE to 1.20, then

10.9/1.20 – 7.9 = 1.18 possessions saved (this value is 3rd among league)

In other words, Lin’s AE at 1.38 plus 1.18 TOs equals to AE at 1.20 （7.9+1.18). Call it AE compensation 1(AE_C1)

Then Lin’s AST/TO ratio is 4.5/(2.7-1.18), which is close to 3:1 with AE at 1.20, very decent.

However, for a player like Harden, many of his TOs come from aggressive scoring (euro step, ISO etc.), which reflects on FT shooting.

Harden makes 8.8 free throws per game at 85%, if we convert it to 56% TS, then

FT*FT%/0.56*2-FT/2 = 2.27 possessions

In other words, if Harden shots 8.8 free throws while TO 2.27 times, net result is decent 56% TS. Call it AE compensation 2 (AE_C2)

Combine AE_C1 and AE_C2, the highest among league are:

1st Durant AE_C1+C2 = 3.35, 2nd LBJ=2.45

3rd LIN=1.18+0.89=2.07, Harden at 4th = -0.3+2.27=1.97

Surprisingly, Lin's compensation value at 3rd despite far low usage rate, it shows Lin has rare combination of both aggressive assist and aggressive scoring. This might be added to the explanations why Lin could pull off wins despite 6 TOs per game during his Linsanity run.

Using C1,C2 to adjust AST/TO ratio,

For Lin, 4.5/(2.7-2.27)= 7.1, which is 3rd among PGs, only Chris Paul 12.98, Marshall 9.81 are higher.



Rondo’s stats is at small sample size this season, he was much better, however about one third of his assist always comes from long 2, probably the most among PG. This doesn't mean that he can’t adjust to Huston’s offense scheme. But it will come at a price.

Because current advance player rating formula such as PER has no reflection on passing efficiency, one can argue player has “high risk high reward” passing style like Lin and parson among others are undervalued, by 1.18 and 0.45 (AE_C1) respectively.