Tag: Basketball


Data supports claim that if Kobe stops ball hogging the Lakers will win more

The Lakers recently snapped a four game losing streak. In that game Kobe, the league leader in field goal attempts and missed shots, had a season low of 14 points but a season high of 14 assists. This makes sense to me since Kobe shooting less means more efficient players are shooting more. Kobe has a lower career true shooting % than Gasol, Howard and Nash (ranked 17,3 and 2 respectively). Despite this he takes more than 1/4 of the shots. Commentators usually praise top scorers no matter what, but recently they have started looking at data and noticed that the Lakers are 6-22 when Kobe has more than 19 field goal attempts and 12-3 in the rest of the games.


This graph shows score differential versus % of shots taken by Kobe* . Linear regression suggests that an increase of 1% in % of shots taken by Kobe results in a drop of 1.16 points (+/- 0.22)  in score differential. It also suggests that when Kobe takes 15% of the shots, the Lakers win by an average of about 10 points, when he takes 30% (not a rare occurrence) they lose by an average of about 5. Of course we should not take this regression analysis to seriously but it's hard to ignore the fact that when Kobe takes less than 23 23.25% of the shots the Lakers are 13-1.

I suspect that this relationship is not unique to Kobe and the Lakers. In general, teams with  a more balanced attack probably do better. Testing this could be a good project for Jeff's class.

* I approximated shots taken as field goal attempts + floor(0.5 x Free Throw Attempts).

Data is here.

Update: Commentator Sidney fixed some entires in the  data file. Data and plot updated.


Why don't we hear more about Adrian Dantley on ESPN? This graph makes me think he was as good an offensive player as Michael Jordan.

In my last post I complained about efficiency not being discussed enough by NBA announcers and commentators. I pointed out that some of the best scorers have relatively low FG% or TS%. However, via the comments it was pointed out that top scorers need to take more difficult shots and thus are expected to have lower efficiency. The plot below (made with this R script) seems to confirm this (click image to enlarge) . The dashed line is from regression and the colors represent guards (green), forwards (orange) and centers (purple).

Among this group TS% does trend down with points per game and centers tend to have higher TS%. Forwards and guards are not very different. However, the plot confirms that some of the supposed all time greats are more ball hogs than good scorers. 

A couple of  further observations. First, Adrian Dantley was way better than I thought. Why isn’t he more famous? Second, Kobe is no Jordan. Also note Jordan played several seasons past his prime which lowered his career averages. So I added points for five of these players using only data from their prime years (ages 24-29). Here Jordan really stands out. But so does Dantley! 

pd - Note that these plots say nothing about defense, rebounding, or passing. This in-depth analysis makes a convincing argument that Dennis Rodman is one of the most valuable players of all time.


This graph makes me think Kobe is not that good, he just shoots a lot

I find it surprising that NBA commentators rarely talk about field goal percentage. Everybody knows that the more you shoot the more you score. But players that score a lot are admired without consideration of their FG%. Of course having a high FG% is not necessarily admirable as many players only take easy shots, while top-scorers need to take difficult ones. Regardless, missing is undesirable and players that miss more than usual are not criticized enough. Iverson, for example, had a lowly career FG% of 43 yet he regularly made the allstar team. But I am not surprised he never won an NBA championship: it’s hard to win when your top scorer misses so often.

Experts consider Kobe to be one of the all time greats and compare him to Jordan. They never mention that he is consistently among league leaders in missed shots. So far this year, Kobe has missed a whopping 279 times for a league leading 13.3 misses per game. In contrast, Lebron has missed 8.8 per game and has scored about the same per game. The plot above (made with this R script) shows career FG% for players considered to be superstars, top-scorers, and that have won multiple championships (red lines are 1st and 3rd quartiles). I also include Gasol, Lebron, Wade, and Dominique. Note that Kobe has the worst FG% in this group.  So how does he win 5 championships? Well perhaps Shaq and later Gasol made up for his misses. Note that the first year Kobe played without Shaq, the Lakers did not make the playoffs. Also, during Kobe’s career the Lakers’ record has been similar with and without him. Experts may compare Kobe to Jordan, but perhaps we should be comparing him to Dominique.

Update: Please see Brunsloe87’s comment for a much better analysis than mine. He/she points out that it’s too simplistic to look at FG%. Instead we should look at something closer to points scored per shot taken. This rewards players, like Kobe, that draw many fouls and has a high FT%. There is a weighted statistic called true scoring % (TS%) that tries to summarize this and below I include a plot of TS% for the same players. Kobe is no Jordan but he is not as bad as Dominique either. He is somewhere in the middle. 

The comment also points out that Magic didn’t shoot as much as other superstars so it’s unfair to include him. A better plot would plot TS% versus shots taken (e.g. FGA+FTA/2) but I’ll let someone with more time make that one. Anyways, this plot explains why the early 80s Lakers (Magic+Kareem) were so good.