Author Archives: dberri

Competitive Imbalance in College Basketball

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My latest for Freakonomics (yes, I wrote two posts this week), focuses on competitive balance in college basketball.  One argument the NCAA offers when people ask why the labor that generates multi-billion dollar television contracts are not actually paid is that paying the student-athletes would disrupt competitive balance.  As I note at Freakonomics, there is a small problem with that argument. 

Okay, it is a big problem. 

Nevertheless… I am still enjoying the tournament (except for the part where Colorado State was eliminated in the first game).

- DJ

Who Could Have Known About Lin?

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The following comes from the talented Greg Steele (aka the Man of Steele). Greg normally writes about the Houston Rockets but as Rockets GM Daryl Morey decided to comment on Jeremy Lin, Greg felt compelled to reply.

It’s not often that a polished Harvard grad gets the short end of the stick. Yet that’s precisely what happened to one graduate of that distinguished institution. Jeremy Lin completed his four-year career at Harvard and prepared to enter a career with extremely high salaries. Despite his pedigree, Lin was not able to catch on in the business for an entire year after graduation.

Of course, Lin’s chosen career field was fairly exclusive: he chose to go into professional basketball. Although Lin accumulated a Position-Adjusted Win Score of 12.96 in his senior year at Harvard, he went undrafted in the 2010 NBA Draft. The average PAWS of college players selected in the NBA Draft is 10.18, so it seems relatively clear that Lin was a good prospect. However, there are two extenuating circumstances:

  • College productivity does not always lead to NBA productivity
  • Lin played in the Ivy League, midmajor or minor conference, and therefore faced weaker competition than many of the players who were drafted

Factor 1) above applies to all prospective rookies, not just Lin, so we’ll set it aside for now. Now, on to factor 2). Let’s say we discount Lin’s PAWS by 10% to account for the fact that his competition was fairly weak. While we’re at it, let’s also discount Lin’s productivity by another 10% to reflect the fact that he entered the draft pool as a senior, and thus had less potential to improve than younger players. So, if we go ahead and discount 20% of Jeremy Lin’s collegiate productivity, he is left with an Adjusted Position-Adjusted Win Score of 10.38 – still above the average production level of an NBA player in college. Actually, there’s no way we should even have an unofficial metric whose acronym is APAWS, since that sounds more like an endearing term for someone’s grandfather than a basketball metric. Instead, let’s call this second number Jeremy Lin’s Prospect Estimate.

Still, nobody saw Jeremy Lin until the past week. In each of his last four games, Lin has scored at least 23 points and handed out at least 7 assists, substantially bolstering the Knicks’ fortunes. In 209 minutes this year, Lin has recorded a 0.256 WP48, well above the level a star player achieves over the course of a season. Still, 209 minutes is a small sample size. How else could we have seen Jeremy Lin coming?

Well, last year Arturo came up with some absolutely smashing rookie performance prediction models (Editor’s note: More detail on that here) . These models, based in part on college performance and in part on preseason numbers, predicted that Lin was a good prospect, with a rookie year WP48 predicted to be somewhere between .055 and .090.

Though Lin only played 285 minutes last season, he managed to produce .157 wins per 48 minutes during that playing time, so I guess you could say that Arturo saw Jeremy Lin coming.

Still, surely Lin was only on the radar of the Wages of Wins network. Houston Rockets GM Daryl Morey, who signed and then waived Jeremy Lin without ever letting him play in a regular season game, said that nobody saw him coming. The New York Knicks don’t seem to have had very high expectations for Lin, since they acquired Baron Davis specifically in order to share the point guard position with Toney Douglas. Obviously the Golden State Warriors didn’t see him coming, since they waived him after last season. It would seem that we have to figure that the Knicks were lucky. After all, nobody really saw him coming.

So here’s someone who was interested in Jeremy Lin in August of 2010. Okay, I give up on the thesis that nobody saw Jeremy Lin coming. Even in the blogosphere, some people thought Jeremy Lin was a viable NBA player. Let’s shift to another question. How could anyone see Jeremy Lin coming? His sample size in the NBA is so small, what other numbers, besides his college performance, can we use to evaluate Jeremy Lin?

In 636 minutes in the D-League last year, Lin put up a 0.211 WP48, totaling 2.8 wins produced. So, even when we search long enough to find a statistically significant sample size (more than 400 minutes), we still find that Jeremy Lin was a good prospect. If only he had gone to Duke instead of Harvard, maybe he would’ve been a household name before last week.

On the other hand, maybe nobody could’ve seen him coming. At the very least, it’s unlikely anyone would predict a young player playing so well in their first four starts. Either way, New York scores … on accident.

-Greg

The NBA’s Latest Revenue Sharing Plan Wouldn’t Have Prevented Carmelo Anthony from Playing in New York

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Across the past few months I have written a number of different stories for the Freakonomics.blog.  And over the weekend, I officially became a contributor to the Freakonomics blog (along with such great people as Ian Ayers, Daniel Hamermesh, Justin Wolfers, etc…).

This morning, my first post as a an official contributor went up— Revenue-Sharing Isn’t Needed to Make NBA Small-Market Teams Competitive.  This post examines the NBA’s new revenue sharing plan and argues that this plan will NOT

  • promote competitive balance
  • prevent “star” players – like LeBron James or Chris Paul – from leaving small market teams.

In fact, as I argue, the NBA already had a mechanism in place to prevent LeBron and CP3 from departing small markets (and obviously that mechanism failed).

When fans think about the James and Paul stories, they often turn to the tale of Carmelo Anthony (at least, for the purpose of this post, that is the turn we are taking).

About a year ago, Carmelo Anthony was traded by the Denver Nuggets (a small market team) to the New York Knicks (a large market team).  At the time, most observers believed the Knicks had taken advantage of the Nuggets.  After all, Carmelo Anthony is an NBA star.  Or at least, that was the conventional wisdom.

Now that almost a year has passed, people (other than people in the Wages of Wins Network – who have always questioned Melo’s “star” status) have begun to question Melo’s star power.

For an example, let’s start with Ethan Sherwood Strauss from Hoopspeak.com:

Carmelo Anthony is a starting forward in the All Star game, despite playing for a team that leavens empty promises with broken dreams. Despite how his old team got dramatically better after trading him. Despite how he’s shooting near 40%. And despite those despites, Charles Barkley was shushed on Inside the NBA for naming Josh Smith as a possible alternative to Melo, the mainstay. Apostasy!

 

There has been a bit of revisionist history regarding the Anthony trade, by the way. It is now known as the Great Denver Talent Haul. Way back in 2011, this was not the case. The Knicks had killed the Nuggets by procuring this deal. Denver had sadly been forced to swap “50 cents on the dollar,” thus dooming Colorado’s Pepsi Center to be the NBA’s haunted, vacant, blood-sloshed Stanley Hotel. All role players, no playoffs, makes George Karl a…

 

Well we know it worked out in the exact opposite manner. Now the Knicks look haunted, the Nuggets look liberated, and Mike D’Antoni’s seat is hot enough to curdle a diamond. And yet, there is a hesitancy to radically reassess our valuation system. The new story is about how the sum of Denver’s parts exceeded a single star’s worth. And while there is certainly merit to this trope, why aren’t more people asking whether Carmelo Anthony is even a star? Is it possible that Denver’s as much cured of Melo as they are well-compensated for his absence?

Sherwood Strauss argues there are better forwards than Melo, noting both Josh Smithand Andre Iguodala specifically.  If we focus just on the small forwards (Smith is more of a power forward), we can see that Melo in 2011-12 isn’t nearly as productive as several other players at the small forward position in the Eastern Conference (numbers from NBA Geek as of Friday night’s games):

These are just the top 5 at this position in the Eastern Conference.  If you keep going down the list of small forwards eventually you see:

An average player posts a WP48 of 0.100.  So Melo has actually been below average this season.  Of course, NBA fans may find this very hard to believe. After all, Anthony ranks in the top 10 in scoring.  How can a top 10 scorer be below average?

As Sherwood Strauss notes, Anthony does take a large number of shots.  But he has trouble getting those shots to go in consistently this season.  Consequently, his shooting efficiency is quite low, and therefore, his overall production of wins isn’t very high.

The debate around Anthony actually gets at another debate in the statistical community.  A few days ago, Mike Kurylo made the following observations in the New York Times:

...statistical analysts vary in how they evaluate the game, and are not in agreement on a multitude of issues. Perhaps the most divisive issue is the value of shot creation.

 

…Some statisticians such as ESPN’s John Hollinger think highly of this skill, and the stat he created Player Efficiency Rating (P.E.R.) has the penalty for a missed shot lower than the reward for a made shot. Players that shoot a lot, even at a low efficiency, tend to have a high P.E.R. On the other end of the spectrum is economist turned N.B.A. analyst David Berri, who heavily penalizes a missed shot in his statistical method Wins Produced (W.P.). Players who make shots at a high percentage, even at a low volume, tend to have a high W.P.
Because of a large number of variables in an N.B.A. game, it is difficult proving where across the spectrum the value of shot creation lies. But the Carmelo Anthony trade, or perhaps the result of it, might shed some light on the subject.

 

If you’re reading this, you probably already know that the Knicks traded a handful of assets (most relevant, Danilo Gallinari and Timofey Mozgov) last season for Anthony and some other players. You’re also likely aware of the intense media pressure in favor of the Knicks trading for Anthony at the time. Last February, ESPN’s Stephen A. Smith wrote “the Knicks must go get Carmelo Anthony as soon as possible,” and “Danilo Gallinari is good, with promise, but hardly worth holding on to if it means not getting Anthony’s services.”

 

Smith’s remarks represent those who put a high demand on shot creation. By this standard, Anthony’s value was perceived to be much greater than that of Gallinari due to the former’s ability to take more shots. Comparing the players’ stats at the same stage in their careers, Anthony is able to take nearly 38 percent more shots than Gallinari. On the other hand, Gallinari’s true shooting percentage, a measure of a player’s overall scoring efficiency, is 45 points higher (59.0 percent to 54.5 percent) than Anthony’s. Hence those who put a low premium on scoring volume and higher value on efficiency saw Anthony as overrated.

Nearly a year later, the result of this trade seems to be that higher efficiency is more valuable than higher volume when it comes to scoring. The Denver Nuggets have a robust 14-6 record, while the New York Knicks have a mediocre record of 7-13. Not that the fortunes of these teams are based on the efforts of a single player, but they embody the opposite sides of the volume/efficiency argument.

 

The Denver Nuggets are a team that lacks a high-volume scorer. If we limit our scope to players with 100 or more minutes on the season, no Nugget player averages more 16.5 field goal attempts per 36 minutes. New York has two players who fit this criteria, Anthony and Amar’e Stoudemire. Of the Denver starters, the highest field goal attempts per 36 minutes is Ty Lawson’s 13.1. Meanwhile, the Knicks have four starters averaging more than that number.

While New York has more players who are able to create shots, Denver has more players who are efficient with their shooting. The Knicks have eight players with a true shooting percentage lower than 55.0 percent, while the Nuggets only have three.

 

Despite lacking a player who can create shots for himself at a high level, the Nuggets have the N.B.A.’s best offense, ranked by offensive efficiency. Meanwhile, the Knicks, with multiple high-volume shooters, find themselves with the league’s 24th-best offense. It appears that the ability to score efficiently is more important than the ability to create shots.

 

…So does this all mean? For basketball analysts it means the high-volume scorer who lacks the ability to sink shots at a mediocre rate is likely overrated by all but a percentage of statisticians. For the Knicks’ current roster, it means that the team has to work on improving the quality and lowering the frequency of shots among their low-efficiency scorers. For the Knicks’ front office it means that perhaps they should abandon their current method of evaluating players and consult with a statistician before their next franchise-altering trade.

Kurylo’s column highlights the essential argument Wins Produced makes:  Players create value when they get their shots to go in the basket.  Just taking shots – shots that are often just “taken” from their teammates – is not a skill teams should reward.

With respect to Carmelo Anthony, the large-market New York Knicks clearly made this mistake.  And the small-market Denver Nuggets have benefitted from this decision.

What does all this have to do with revenue-sharing (the topic that started this discussion)?  Well, the revenue sharing plan – as noted at Freakonomics – would not have prevented Carmelo Anthony from forcing a trade from Denver to New York.  Of course – as I have noted in the past (and as Andres Alvarez did earlier today) – the Knicks could now only wish there was some mechanism to prevent these kind of decisions.  As it is, it looks like the Knicks are married to Melo.  And that probably means, the Knicks are not going to be part of a championship parade in the near future (unless they go watch the Giants parade).

- DJ

Are the Jazz winning because they have the best power forward in the NBA?

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The Utah Jazz played four games in December.  Of these, three were losses.  Furthermore, the Jazz were out-scored by 54 points in these four contests.  Given these results, the mood in Utah wasn’t too good as 2012 began.

Once the calender turned to 2012, though, something happened with the Jazz.  In January the Jazz are 9-2.  And Utah now has the third best winning percentage in the Western Conference.

Before we get to why the Jazz are suddenly so good, we should note that the Jazz are not quite as good as their record indicates.  To illustrate, here is a ranking of all teams in the Western Conference by efficiency differential (offensive efficiency minus defensive efficiency, as of Sunday morning):

  • Denver Nuggets: 5.4
  • Oklahoma City Thunder: 5.1
  • Memphis Grizzlies: 3.8
  • Dallas Mavericks: 3.7
  • San Antonio Spurs: 3.0
  • Portland Trail Blazers: 2.9
  • Utah Jazz: 2.5
  • Los Angeles Lakers: 2.2
  • Minnesota Timberwolves: 1.4
  • Los Angeles Clippers: 0.50
  • Houston Rockets: -0.1
  • Phoenix Suns: -2.0
  • Golden State Warriors: -4.0
  • New Orleans Hornets: -5.2
  • Sacramento Kings: -11.6

In terms of differential, the Jazz only rank 7th in the conference.  So Utah’s record is a bit deceptive.  Still, the Jazz appear to be have improved.  Last season the Jazz only won 39 games with a -1.9 differential.  Additionally that mark was when we consider the full season. The Jazz started out last season with Deron Williams playing well and traded him mid-season. So the Jazz actually ended last season as a worse team than they appeared.

In addition to the loss of Williams, the Jazz also said good-bye to Andrei Kirilenko (8.7 Wins Produced and 0.209 WP48 – or Wins Produced per 48 minutes).   To replenish the roster, the Jazz added Enes Kanter and Alec Burks in the draft and signed Josh Howard and Jamaal Tinsley.  Obviously Kanter and Burks had never played in the NBA.  And Howard and Tinsley hadn’t played more than 1,000 minutes in an NBA season since 2008-09 and 2007-08 respectively.  Such additions didn’t exactly inspire much hope that the Jazz were on the verge of a playoff berth in 2012.  Yet, that now seems a possibility.

So what happened? To answer this question, let’s look at the 2011-12 Wins Produced numbers for the Jazz from Patrick Minton the NBA Geek himself (@nbageek)

2011-2012 Utah Jazz through January 21st 2012
Player Position Games Minutes Points
per 48
minutes		 WP48 Wins
Produced		 WP for
66 games
Paul Millsap PF 15 451 26.5 0.309 2.90 12.8
Earl Watson PG 15 316 9.4 0.168 1.10 4.8
Enes Kanter C 15 209 16.3 0.210 0.91 4.0
Al Jefferson C 14 465 26.4 0.077 0.74 3.3
Gordon Hayward SF 15 395 15.3 0.076 0.63 2.8
Raja Bell SG 15 340 12.0 0.072 0.51 2.2
Derrick Favors PF 14 276 17.4 0.089 0.51 2.2
Jeremy Evans SF 8 53 19.0 0.404 0.45 2.0
Devin Harris PG 15 381 15.4 0.038 0.30 1.3
Josh Howard SF 11 253 22.4 0.048 0.25 1.1
Jamaal Tinsley PG 7 35 4.1 0.151 0.11 0.5
Alec Burks SG 14 178 24.0 0.025 0.09 0.4
C.J. Miles SF 15 274 24.7 0.014 0.08 0.4
Sum of WP 37.8

If the team’s Wins Produced after 15 games continues throughout the 66 game season, this team can expect to win about 38 games.  Of these 38 wins, about 21.6 can be linked to the play of Paul Millsap, Earl Watson, and Enes Kanter.

An average NBA player offers a 0.100 WP48 and so far Kanter is twice as good as an average player.  And last season, Millsap and Watson were about average, posting a 0.133 and 0.091 WP48 respectively.  If all these players were average in 2010-11, this trio would only be on pace to produce 8.9 wins this year.  That would mean the Jazz would only be on pace as a team to win about 25 games this year.  In other words, if this trio were average – which would have been a reasonable expectation – the Jazz would be about what we might have expected before the season started.

But these players are not average.  So what’s changed?

Let’s start with Kanter.  He is a rookie, and rookies are hard to forecast.   Kanter is especially hard to forecast, since he didn’t play college basketball.  Nevertheless, it is unusual for rookies to play quite this well.  When we look at the numbers – again from Patrick Minton and theNBAGeek – we see that Kanter is above average (relative to an average center) with respect to true shooting percentage (driven by an ability to get to the free throw line and hit those shots at the line) and rebounding.

Following the same process with respect to Watson, we see that Watson is – relative to his career average – doing better with respect to shooting efficiency, defensive rebounds, blocked shots (really), and assists.  These improvements have resulted in the highest WP48 marks of Watson’s career.

A similar story can be told for Millsap.  Thus far in 2011-12 his WP48 is a career high.  When we look at the individual stats we see that Millsap is posting career high numbers with respect to shooting efficiency from the field, field goal attempts, steals, turnovers (career low), and personal fouls (tied for career low).

If there is a trend in these numbers (and really – with a sample of three – we can’t call it a “trend”) we see that these players are hitting some shots.  And if that continues, the Jazz will continue to win a bit more often.

Again, the person leading the team to more wins is Millsap.  And Millsap isn’t just leading the Jazz in Wins Produced.  Millsap in 2011-12 is currently the most productive power forward in the game.

Again, we turn to Patrick’s numbers(sort by power forward if you wish to see the complete list).  Here are the top 10 power forwards this season (before Sunday’s games):

In looking at these names it is important to note who is not in the top 10.  Chris Bosh, Blake Griffin, Dirk Nowitzki, and Kevin Garnett are all currently offering less than these 10 players.

So does that mean these 10 are all “better” than this quartet of All-Stars? Baseball fans may be better equipped to answer this. The Phillies first baseman Ryan Howard posted a 0.835 OPS in 2011, a mark that ranked 36th in the league.  Such a ranking suggests the Phillies should be trying to trade Howard for any of the 35 players ranked ahead of Howard.  But is that the case?  Maybe not.  We are only looking at one season of performance, and we might want to consider more before suggesting trades.  Players can have up and down seasons.

So it might be a bit premature to argue that Millsap is the “best” power forward in the NBA. It does appear, though, that across the first 25% of 2011-12, Millsap has been the most productive power forward in the game.

As great as Millsap has played, though, he currently ranks second on the Jazz in WP48. The leader on this team is Jeremy Evans.  Across 53 minutes, Evans has posted a 0.404 WP48.  Last season – as a rookie — Evans posted a 0.311 WP48 in 463 minutes.   So Evans hasn’t played much in the NBA.  But he has played more than 500 career minutes against other NBA players (perhaps not the best NBA players, but these weren’t high school players he was facing) and he has been very productive.  Such numbers suggest that maybe the Jazz should find more minutes for Evans.

Surprisingly, this season the Jazz may find a way to still compete despite losing some of their good players (Deron Williams and Andrei Kirilenko). Of course, it helps if they consistently player their most productive players.   If the Jazz are willing to play Evans more, they may find winning even easier. And if they Jazz decide not to play Evans… well, maybe another team should give him a shot.  In limited minutes, Evans has really been quite amazing so far.

- DJ

Are Celtics fans disappointed in Garnett and Pierce?

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The Celtics are now 4-7.  On Saturday morning – before the Celtics lost to the Pacers (Boston’s fourth consecutive loss) – Chris Mannix of Sports Illustrated wrote the following.

Are the Celtics old? Of course.
Is that why they are 4-6? Absolutely not.

A reading of the Mannix article reveals that he does think age is playing a role in Boston.  But he also thinks more is going on.

I am not sure I entirely agree with what Mannix had to say.  And my disagreement primarily comes from the fact Mannix isn’t all that specific as to the nature Boston’s problem.  He does note that a team that is 4-7 needs better players.  But before Boston starts finding better players, we might want to figure out which players are responsible for what we have seen so far this season. As is often the case, let’s look at some numbers.

The Celtics then and now

Let’s start with the big picture.  The Celtics won 56 games in 2010-11.  The team’s efficiency differential – offensive efficiency minus defensive efficiency – was 5.8.  This mark ranked 6th in the NBA.   This season the Celtics have a differential of -2.4, which ranked 20th in the league.  Such a mark is consistent with a team that would win 35 games across an 82 game season.  So the Celtics – relative to last year – have lost about 20 wins.

At this point, the big picture numbers tell us what everyone – including Mannix — has seen.  The Celtics are not as good as they were last year.

When we move from efficiency differential to each player’s productivity, we can identify who is specifically responsible for Boston’s decline.

Last year the productivity of Boston’s players was as follows (numbers taken from the amazing Patrick Minton – or the NBA Geek):

Celtics Positions Games Minutes WP48 Points
per 48
minutes		 Wins
Produced
Ray Allen SG 80 2890 0.205 21.9 12.3
Rajon Rondo PG 68 2523 0.233 13.7 12.2
Paul Pierce SF 80 2779 0.203 26.1 11.7
Kevin Garnett PF 71 2218 0.225 22.9 10.4
Marquis Daniels SF 49 938 0.166 13.9 3.3
Shaquille O’Neal C 37 751 0.138 21.8 2.2
Delonte West SG 24 453 0.143 14.3 1.4
Von Wafer SG 58 555 0.092 15.9 1.1
Nenad Krstic C 24 552 0.090 19 1.0
Jeff Green PF 26 612 0.048 19.9 0.6
Glen Davis C 78 2301 0.012 19.1 0.6
Semih Erden C 37 530 0.051 13.6 0.6
Kendrick Perkins C 12 314 0.084 13.3 0.6
Troy Murphy PF 17 179 0.094 11.8 0.4
Carlos Arroyo PG 15 190 0.043 9.1 0.2
Luke Harangody PF 28 240 0.032 12.6 0.2
Sasha Pavlovic SF 17 149 0.034 10 0.1
Chris Johnson C 4 33 0.096 8.7 0.1
Jermaine O’Neal C 24 432 -0.045 14.3 -0.4
Nate Robinson PG 55 989 -0.021 18.8 -0.4
Avery Bradley PG 31 165 -0.242 15.1 -0.8
Sum of
Wins
Produced		 57.1

Last year the Celtics received 46.7 wins from Ray Allen, Rajon Rondo, Paul Pierce, and Kevin Garnett.  And the team received 10.4 wins from everyone outside this quartet.
Now let’s look at the Celtics after 11 games:

Celtics Positions Games Minutes WP48 Points
per 48
minutes		 Wins
Produced		 WP
for
66 games
Ray Allen SG 10 352 0.250 23.9 1.83 11.0
Rajon Rondo PG 11 405 0.210 19.2 1.77 10.6
Brandon Bass PF 11 306 0.087 20.5 0.55 3.3
Greg Stiemsma C 9 102 0.256 10.8 0.54 3.2
Kevin Garnett PF 11 343 0.072 20.7 0.51 3.1
Paul Pierce SF 8 253 0.068 22.2 0.36 2.2
JaJuan Johnson FC 7 18 0.230 26.7 0.09 0.5
Chris Wilcox C 7 53 0.071 10.0 0.08 0.5
E’Twaun Moore G 7 40 -0.017 16.8 -0.01 -0.1
Sasha Pavlovic SF 6 70 -0.039 11.7 -0.06 -0.4
Keyon Dooling PG 9 166 -0.042 18.2 -0.14 -0.8
Jermaine O’Neal C 10 226 -0.033 10.6 -0.15 -0.9
Mickael Pietrus SF 3 54 -0.138 13.3 -0.16 -1.0
Avery Bradley PG 11 101 -0.131 10.0 -0.28 -1.7
Marquis Daniels SF 9 152 -0.091 10.1 -0.29 -1.7
Sum of
Wins
Produced		 4.64 27.84

So far, Ray Allen and Rajon Rondo are still producing.  And everyone else – outside the team’s four superstars – is on pace to produce 7.6 wins (across an 82 game season).  So it doesn’t appear that Allen, Rondo, or everyone else is the problem.

Obviously that allows us to identify the problem.  Kevin Garnett has only produced 0.5 wins across the first 11 games.  At this pace – if this were a full 82 game season – he would produce only 3.8 wins across a complete season.  In other words, KG is on pace to produced 6.6 fewer wins (again, across a full 82 game season).

Why is KG slipping?  If we focus on scoring (see KG’s career per 48 minute numbers at NBA Geek) we don’t see too big of a drop-off (per 48 minutes KG’s scoring has dropped from 22.9 to 20.7).  The drop-off we do see with respect to scoring, though, is not really about shot attempts.  Garnett is still shooting.  Unfortunately, relative to last year, these shots are not going in the basket as often.  In addition, KG is not rebounding as well.  These two issues have caused KG to go from being the above average player he has always been to a below average performer thus far in 2011-12.

Below average also describes Paul Pierce.  Relative to last year, Pierce’s rebounding and assists are up.  And his personal fouls are down.  But his turnovers are up and his blocked shots are down.  These changes, though, are not the big story.  Thus far this season, Pierce has an effective field goal percentage (or adjusted field goal percentage) of 45.7%.  Last season his mark was 55.1%.  It is this decline that essentially has caused Pierce’s Wins Produced – again, across 82 games – to fall from 11.7 in 2010-11 to a 2.7 pace for 2011-12.

If we put the decline we see with respect to Pierce and Garnett together, we see that these two players are responsible for a drop-off of 15.7 wins across a full season. Again, the team has declined by about 20 wins across an 82 game season.  And about 75% of that decline is linked to two players who happened to be 35 (KG) and 34 (Pierce) years of age.   So that suggests – contrary to what Mannix said – that age might be a problem.

From Stumbling on Wins we learn that basketball players

  • tend to peak around their mid-20s
  • tend to decline slowly in their latter-twenties
  • tend to decline at a more accelerated pace in their thirties

Those tendencies are just that, tendencies.  We do not know how each specific player will age.  So we should not be shocked that Ray Allen – who is 36 – still seems productive.  But we do know that at some point (and this is true for Allen), age will take its toll.  At some point, all the aging stars on the Celtics will stop producing.
Has that time truly come for KG and Pierce?  After 11 games it looks that way.  But 11 games is still a small sample.  It’s very possible for KG and Pierce to comeback this year.

So far in 2010-11, it is the decline in KG and Pierce’s performance that is driving what we see in Boston. And until these two players start producing (still possible) or the Celtics find that kind of production elsewhere (perhaps less likely during the season), Boston fans are going to be disappointed.  But at least now, they can see who is responsible for their disappointment.

- DJ